U.S. patent application number 16/854092 was filed with the patent office on 2020-08-06 for process for production of acrylic acid.
The applicant listed for this patent is Novomer, Inc.. Invention is credited to Jay J. Farmer, Peter Galebach, Kyle Sherry, Sadesh H. Sookraj.
Application Number | 20200247742 16/854092 |
Document ID | / |
Family ID | 1000004767944 |
Filed Date | 2020-08-06 |
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United States Patent
Application |
20200247742 |
Kind Code |
A1 |
Farmer; Jay J. ; et
al. |
August 6, 2020 |
PROCESS FOR PRODUCTION OF ACRYLIC ACID
Abstract
Provided are integrated processes for the conversion of beta
propiolactone to acrylic acid. Systems for the production of
acrylic acid are also provided.
Inventors: |
Farmer; Jay J.; (Rochester,
NY) ; Galebach; Peter; (Rochester, NY) ;
Sherry; Kyle; (Rochester, NY) ; Sookraj; Sadesh
H.; (Rochester, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novomer, Inc. |
Rochester |
NY |
US |
|
|
Family ID: |
1000004767944 |
Appl. No.: |
16/854092 |
Filed: |
April 21, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16107858 |
Aug 21, 2018 |
10626073 |
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16854092 |
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15550193 |
Aug 10, 2017 |
10099988 |
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PCT/US2016/017868 |
Feb 12, 2016 |
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16107858 |
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62116325 |
Feb 13, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y02P 20/10 20151101;
C07C 57/04 20130101; C07C 51/09 20130101 |
International
Class: |
C07C 51/09 20060101
C07C051/09; C07C 57/04 20060101 C07C057/04 |
Claims
1-3. (canceled)
4. A method for producing acrylic acid, comprising: (a) providing a
feedstock stream comprising beta propiolactone; (b) directing the
feedstock stream to a first reaction zone; (c) contacting the
feedstock stream with a polymerization catalyst; (d) polymerizing
at least a portion of the beta propiolactone to a
poly(propiolactone) product stream, wherein the first reaction zone
is maintained at a temperature to promote formation of
poly(propiolactone); (e) directing the poly(propiolactone) product
stream to a second reaction zone, wherein the second reaction zone
is maintained at a temperature at or above the pyrolysis
temperature of poly(propiolactone) such that the thermal
decomposition of poly(propiolactone) produces acrylic acid; and (f)
withdrawing an acrylic acid product stream from the second reaction
zone.
5. The method of claim 4, wherein the first reaction zone and
second reaction zone are in an extruder reactor.
6. The method of claim 5, wherein the extruder reactor provides a
temperature gradient between the first reaction zone and second
reaction zone.
7. The method of claim 5, wherein the extruder reactor has a
terminal temperature at or above the pyrolysis temperature of
poly(propiolactone).
8. The method of claim 4, further comprising capturing heat
generated from the first reaction zone, and directing the heat to
other processes.
9. The method of claim 8, wherein the heat is directed to the
second reaction zone.
10-21. (canceled).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application No. 62/116,325, filed Feb. 13, 2015, which is
incorporated herein by reference in its entirety.
FIELD
[0002] The present disclosure relates generally to the production
of acrylic acid, and more specifically to the production of acrylic
acid from beta propiolactone.
BACKGROUND
[0003] Superabsorbent polymers (SAPs) are used in a variety of
industrial and consumer applications, ranging from disposable
hygiene products to cable water blocking. SAPs are mostly commonly
manufactured by polymerization of acrylic acid. Acrylic acid
production is a large industry that uses variety of methods having
a range of cost efficiencies and yielding acrylic acid of varying
purity. Given the size of the acrylic acid market and the
importance of downstream applications of acrylic acid, there is a
need for methods for producing acrylic acid with increased
efficiency.
[0004] Methods have been described where beta propiolactone (BPL)
is converted to acrylic acid (AA) by heating in the presence of
water or alcohols, which act as catalysts to open the BPL to
hydracrylic acid (3-hydroxy propionic acid) or hydracrylic acid
esters, respectively. However, these methods are ill-suited to the
production of glacial acrylic acid (GAA) because the water or
alcohol used to catalyze the reaction can contaminate the acrylic
acid stream. Thus, alternative methods to produce acrylic acid are
desired.
BRIEF SUMMARY
[0005] In some aspects, provided is a method for producing acrylic
acid, comprising:
[0006] (a) providing a feedstock stream comprising beta
propiolactone;
[0007] (b) directing the feedstock stream to a reaction zone where
it is contacted with a suitable polymerization catalyst and where
at least a portion of the beta propiolactone is converted to
poly(propiolactone);
[0008] (c) maintaining the reaction zone at a temperature at or
above the pyrolysis temperature of poly(propiolactone) such that
the thermal decomposition of poly(propiolactone) produces acrylic
acid; and
[0009] (d) withdrawing an acrylic acid product stream from the
reaction zone;
[0010] wherein steps (b) and (c) occur in the same reaction
zone.
[0011] In other aspects, provided is a method for producing acrylic
acid, comprising:
[0012] (a) providing a feedstock stream comprising beta
propiolactone;
[0013] (b) directing the feedstock stream to a first reaction zone,
wherein the feedstock stream is contacted with a polymerization
catalyst and wherein at least a portion of the beta propiolactone
is converted to a poly(propiolactone) product stream, wherein the
first reaction zone is maintained at a temperature suitable for the
formation of poly(propiolactone);
[0014] (c) directing the poly(propiolactone) product stream to a
second reaction zone, wherein the second reaction zone is
maintained at a temperature at or above the pyrolysis temperature
of poly(propiolactone) such that the thermal decomposition of
poly(propiolactone) produces acrylic acid; and (d) withdrawing an
acrylic acid product stream the second reaction zone.
[0015] In other aspects, provided is a system for converting beta
propiolactone to acrylic acid, comprising:
[0016] (a) beta propiolactone; and
[0017] (b) a cationic solid catalyst comprising a carboxylate
salt;
[0018] wherein at or above the pyrolysis temperature of
poly(propiolactone), beta propiolactone begins polymerizing to
poly(propiolactone) in the presence of the cationic solid catalyst,
which poly(propiolactone) concurrently thermally decomposes to
acrylic acid; and
[0019] wherein acrylic acid formed in situ maintains the reaction
polymerizing beta propiolactone to poly(propiolactone).
[0020] In yet other aspects, provided is a system for converting
beta propiolactone to acrylic acid, comprising:
[0021] (a) a reaction zone comprising beta propiolactone (BPL) and
a cationic solid catalyst comprising a carboxylate salt;
[0022] wherein at or above the pyrolysis temperature of
poly(propiolactone) (PPL), BPL begins polymerizing to PPL, which
PPL concurrently thermally decomposes to acrylic acid; and
[0023] (b) a return loop for providing acrylic acid to the reaction
zone.
DEFINITIONS
[0024] Definitions of specific functional groups and chemical terms
are described in more detail below. The chemical elements are
identified in accordance with the Periodic Table of the Elements,
CAS version, Handbook of Chemistry and Physics, 75.sup.th Ed.,
inside cover, and specific functional groups are generally defined
as described therein. Additionally, general principles of organic
chemistry, as well as specific functional moieties and reactivity,
are described in Organic Chemistry, Thomas Sorrell, University
Science Books, Sausalito, 1999; Smith and March March's Advanced
Organic Chemistry, 5.sup.th Edition, John Wiley & Sons, Inc.,
New York, 2001; Larock, Comprehensive Organic Transformations, VCH
Publishers, Inc., New York, 1989; Carruthers, Some Modern Methods
of Organic Synthesis, 3.sup.rd Edition, Cambridge University Press,
Cambridge, 1987.
[0025] The terms "halo" and "halogen" as used herein refer to an
atom selected from fluorine (fluoro, --F), chlorine (chloro, --Cl),
bromine (bromo, --Br), and iodine (iodo, --I).
[0026] The term "aliphatic" or "aliphatic group", as used herein,
denotes a hydrocarbon moiety that may be straight-chain (i.e.,
unbranched), branched, or cyclic (including fused, bridging, and
spiro-fused polycyclic) and may be completely saturated or may
contain one or more units of unsaturation, but which is not
aromatic. In some variations, the aliphatic group is unbranched or
branched. In other variations, the aliphatic group is cyclic.
Unless otherwise specified, in some variation, aliphatic groups
contain 1-30 carbon atoms. In some embodiments, aliphatic groups
contain 1-12 carbon atoms. In some embodiments, aliphatic groups
contain 1-8 carbon atoms. In some embodiments, aliphatic groups
contain 1-6 carbon atoms. In some embodiments, aliphatic groups
contain 1-5 carbon atoms, in some embodiments, aliphatic groups
contain 1-4 carbon atoms, in yet other embodiments aliphatic groups
contain 1-3 carbon atoms, and in yet other embodiments aliphatic
groups contain 1-2 carbon atoms. Suitable aliphatic groups include,
for example, linear or branched, alkyl, alkenyl, and alkynyl
groups, and hybrids thereof such as (cycloalkyl)alkyl,
(cycloalkenyl)alkyl or (cycloalkyl)alkenyl.
[0027] The term "heteroaliphatic," as used herein, refers to
aliphatic groups wherein one or more carbon atoms are independently
replaced by one or more atoms selected from the group consisting of
oxygen, sulfur, nitrogen, phosphorus, or boron. In some
embodiments, one or two carbon atoms are independently replaced by
one or more of oxygen, sulfur, nitrogen, or phosphorus.
Heteroaliphatic groups may be substituted or unsubstituted,
branched or unbranched, cyclic or acyclic, and include
"heterocycle," "hetercyclyl," "heterocycloaliphatic," or
"heterocyclic" groups. In some variations, the heteroaliphatic
group is branched or unbranched. In other variations, the
heteroaliphatic group is cyclic. In yet other variations, the
heteroaliphatic group is acyclic.
[0028] The term "acrylate" or "acrylates" as used herein to refer
to any acyl group having a vinyl group adjacent to the acyl
carbonyl. The terms encompass mono-, di- and tri-substituted vinyl
groups. Acrylates may include, for example, acrylate, methacrylate,
ethacrylate, cinnamate (3-phenylacrylate), crotonate, tiglate, and
senecioate.
[0029] The terms "crude acrylic acid" and "glacial acrylic acid",
as used herein, describe acrylic acid of relatively low and high
purity, respectively. Crude acrylic acid (also called technical
grade acrylic acid) has a typical minimum overall purity level of
94% and can be used to make acrylic esters for paint, adhesive,
textile, paper, leather, fiber, and plastic additive applications.
Glacial acrylic acid has a typical overall purity level ranging
from 98% to 99.99% and can be used to make polyacrylic acid for
superabsorbent polymers (SAPs) in disposable diapers, training
pants, adult incontinence undergarments and sanitary napkins.
Polyacrylic acid is also used in compositions for paper and water
treatment, and in detergent co-builder applications. In some
variations, acrylic acid has a purity of at least 98%, at least
98.5%, at least 99%, at least 99.1%, at least 99.2%, at least
99.3%, at least 99.4%, at least 99.5%, at least 99.6%, at least
99.7%, at least 99.8%, or at least 99.9%; or between 99% and
99.95%, between 99.5% and 99.95%, between 99.6% and 99.95%, between
99.7% and 99.95%, or between 99.8% and 99.95%.
[0030] Impurities in glacial acrylic acid are reduced to an extent
possible to facilitate a high-degree of polymerization to acrylic
acid polymers (PAA) and avoid adverse effects from side products in
end applications. For example, aldehyde impurities in acrylic acid
hinder polymerization and may discolor the polymerized acrylic
acid. Maleic anhydride impurities form undesirable copolymers which
may be detrimental to polymer properties. Carboxylic acids, e.g.,
saturated carboxylic acids that do not participate in the
polymerization, can affect the final odor of PAA or SAP-containing
products and/or detract from their use. For example, foul odors may
emanate from SAP that contains acetic acid or propionic acid and
skin irritation may result from SAP that contains formic acid. The
reduction or removal of impurities from petroleum-based acrylic
acid is costly, whether to produce petroleum-based crude acrylic
acid or petroleum-based glacial acrylic acid. Such costly
multistage distillations and/or extraction and/or crystallizations
steps are generally employed (e.g., as described in U.S. Pat. Nos.
5,705,688 and 6,541,665).
[0031] The term "polymer", as used herein, refers to a molecule
comprising multiple repeating units. In some variations, the
polymer is a molecule of high relative molecular mass, the
structure of which comprises the multiple repetition of units
derived, actually or conceptually, from molecules of low relative
molecular mass. In some embodiments, a polymer is comprised of only
one monomer species (e.g., polyethylene oxide). In some
embodiments, the polymer is a copolymer, terpolymer, heteropolymer,
block copolymer, or tapered heteropolymer of one or more epoxides.
In one variation, the polymer may be a copolymer, terpolymer,
heteropolymer, block copolymer, or tapered heteropolymer of two or
more monomers.
[0032] The term "unsaturated", as used herein, means that a moiety
has one or more double or triple bonds.
[0033] The terms "cycloaliphatic", "carbocycle", or "carbocyclic",
used alone or as part of a larger moiety, refer to a saturated or
partially unsaturated cyclic aliphatic monocyclic, bicyclic, or
polycyclic ring systems, as described herein, having from 3 to 12
members, wherein the aliphatic ring system is optionally
substituted as defined above and described herein. Cycloaliphatic
groups include, for example, cyclopropyl, cyclobutyl, cyclopentyl,
cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl,
cycloheptenyl, cyclooctyl, cyclooctenyl, and cyclooctadienyl. In
some embodiments, the cycloalkyl has 3-6 carbons. The terms
"cycloaliphatic", "carbocycle" or "carbocyclic" also include
aliphatic rings that are fused to one or more aromatic or
nonaromatic rings, such as decahydronaphthyl or tetrahydronaphthyl,
where the radical or point of attachment is on the aliphatic ring.
In some embodiments, a carbocyclic groups is bicyclic. In some
embodiments, a carbocyclic group is tricyclic. In some embodiments,
a carbocyclic group is polycyclic.
[0034] The term "alkyl," as used herein, refers to a saturated
hydrocarbon radical. In some variations, the alkyl group is a
saturated, straight- or branched-chain hydrocarbon radicals derived
from an aliphatic moiety containing between one and six carbon
atoms by removal of a single hydrogen atom. Unless otherwise
specified, in some variations, alkyl groups contain 1-12 carbon
atoms. In some embodiments, alkyl groups contain 1-8 carbon atoms.
In some embodiments, alkyl groups contain 1-6 carbon atoms. In some
embodiments, alkyl groups contain 1-5 carbon atoms, in some
embodiments, alkyl groups contain 1-4 carbon atoms, in yet other
embodiments alkyl groups contain 1-3 carbon atoms, and in yet other
embodiments alkyl groups contain 1-2 carbon atoms. Alkyl radicals
may include, for example, methyl, ethyl, n-propyl, isopropyl,
n-butyl, iso-butyl, sec-butyl, sec-pentyl, iso-pentyl, tert-butyl,
n-pentyl, neopentyl, n-hexyl, sec-hexyl, n-heptyl, n-octyl,
n-decyl, n-undecyl, and dodecyl.
[0035] The term "alkenyl," as used herein, denotes a monovalent
group having at least one carbon-carbon double bond. In some
variations, the alkenyl group is a monovalent group derived from a
straight- or branched-chain aliphatic moiety having at least one
carbon-carbon double bond by the removal of a single hydrogen atom.
Unless otherwise specified, in some variations, alkenyl groups
contain 2-12 carbon atoms. In some embodiments, alkenyl groups
contain 2-8 carbon atoms. In some embodiments, alkenyl groups
contain 2-6 carbon atoms. In some embodiments, alkenyl groups
contain 2-5 carbon atoms, in some embodiments, alkenyl groups
contain 2-4 carbon atoms, in yet other embodiments alkenyl groups
contain 2-3 carbon atoms, and in yet other embodiments alkenyl
groups contain 2 carbon atoms. Alkenyl groups include, for example,
ethenyl, propenyl, butenyl, and 1-methyl-2-buten-1-yl.
[0036] The term "alkynyl," as used herein, refers to a monovalent
group having at least one carbon-carbon triple bond. In some
variations, the alkynyl group is a monovalent group derived from a
straight- or branched-chain aliphatic moiety having at least one
carbon-carbon triple bond by the removal of a single hydrogen atom.
Unless otherwise specified, in some variations, alkynyl groups
contain 2-12 carbon atoms. In some embodiments, alkynyl groups
contain 2-8 carbon atoms. In some embodiments, alkynyl groups
contain 2-6 carbon atoms. In some embodiments, alkynyl groups
contain 2-5 carbon atoms, in some embodiments, alkynyl groups
contain 2-4 carbon atoms, in yet other embodiments alkynyl groups
contain 2-3 carbon atoms, and in yet other embodiments alkynyl
groups contain 2 carbon atoms. Representative alkynyl groups
include, for example, ethynyl, 2-propynyl (propargyl), and
1-propynyl.
[0037] The term "carbocycle" and "carbocyclic ring" as used herein,
refers to monocyclic and polycyclic moieties wherein the rings
contain only carbon atoms. Unless otherwise specified, carbocycles
may be saturated, partially unsaturated or aromatic, and contain 3
to 20 carbon atoms. Representative carbocycles include, for
example, cyclopropane, cyclobutane, cyclopentane, cyclohexane,
bicyclo[2,2,1]heptane, norbornene, phenyl, cyclohexene,
naphthalene, and spiro[4.5]decane.
[0038] The term "aryl" used alone or as part of a larger moiety as
in "aralkyl", "aralkoxy", or "aryloxyalkyl", refers to monocyclic
and polycyclic ring systems having a total of five to 20 ring
members, wherein at least one ring in the system is aromatic and
wherein each ring in the system contains three to twelve ring
members. The term "aryl" may be used interchangeably with the term
"aryl ring". In some embodiments, "aryl" refers to an aromatic ring
system which includes, for example, phenyl, naphthyl, and
anthracyl, which may bear one or more substituents. Also included
within the scope of the term "aryl", as it is used herein, is a
group in which an aromatic ring is fused to one or more additional
rings, such as benzofuranyl, indanyl, phthalimidyl, naphthimidyl,
phenanthridinyl, and tetrahydronaphthyl.
[0039] The terms "heteroaryl" and "heteroar-", used alone or as
part of a larger moiety, e.g., "heteroaralkyl", or
"heteroaralkoxy", refer to groups having 5 to 14 ring atoms,
preferably 5, 6, 9 or 10 ring atoms; having 6, 10, or 14 pi (.pi.)
electrons shared in a cyclic array; and having, in addition to
carbon atoms, from one to five heteroatoms. The term "heteroatom"
refers to nitrogen, oxygen, or sulfur, and includes any oxidized
form of nitrogen or sulfur, and any quaternized form of a basic
nitrogen. Heteroaryl groups include, for example, thienyl, furanyl,
pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl,
isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl, thiadiazolyl,
pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl, purinyl,
naphthyridinyl, benzofuranyl and pteridinyl. The terms "heteroaryl"
and "heteroar-", as used herein, also include groups in which a
heteroaromatic ring is fused to one or more aryl, cycloaliphatic,
or heterocyclyl rings, where the radical or point of attachment is
on the heteroaromatic ring. Examples include indolyl, isoindolyl,
benzothienyl, benzofuranyl, dibenzofuranyl, indazolyl,
benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl, cinnolinyl,
phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl,
carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl,
tetrahydroquinolinyl, tetrahydroisoquinolinyl, and
pyrido[2,3-b]-1,4-oxazin-3(4H)one. A heteroaryl group may be mono-
or bicyclic. The term "heteroaryl" may be used interchangeably with
the terms "heteroaryl ring", "heteroaryl group", or
"heteroaromatic", any of which terms include rings that are
optionally substituted. The term "heteroaralkyl" refers to an alkyl
group substituted by a heteroaryl, wherein the alkyl and heteroaryl
portions independently are optionally substituted.
[0040] As used herein, the terms "heterocycle", "heterocyclyl",
"heterocyclic radical", and "heterocyclic ring" are used
interchangeably and may be saturated or partially unsaturated, and
have, in addition to carbon atoms, one or more, preferably one to
four, heteroatoms, as defined above. In some variations, the
heterocyclic group is a stable 5- to 7-membered monocyclic or 7- to
14-membered bicyclic heterocyclic moiety that is either saturated
or partially unsaturated, and having, in addition to carbon atoms,
one or more, preferably one to four, heteroatoms, as defined above.
When used in reference to a ring atom of a heterocycle, the term
"nitrogen" includes a substituted nitrogen. As an example, in a
saturated or partially unsaturated ring having 0-3 heteroatoms
selected from oxygen, sulfur or nitrogen, the nitrogen may be N (as
in 3,4-dihydro-2H-pyrrolyl), NH (as in pyrrolidinyl), or .sup.+NR
(as in N-substituted pyrrolidinyl).
[0041] A heterocyclic ring can be attached to its pendant group at
any heteroatom or carbon atom that results in a stable structure
and any of the ring atoms can be optionally substituted. Examples
of such saturated or partially unsaturated heterocyclic radicals
include, for example, tetrahydrofuranyl, tetrahydrothienyl,
pyrrolidinyl, pyrrolidonyl, piperidinyl, pyrrolinyl,
tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl,
oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl, diazepinyl,
oxazepinyl, thiazepinyl, morpholinyl, and quinuclidinyl. The terms
"heterocycle", "heterocyclyl", "heterocyclyl ring", "heterocyclic
group", "heterocyclic moiety", and "heterocyclic radical", are used
interchangeably herein, and also include groups in which a
heterocyclyl ring is fused to one or more aryl, heteroaryl, or
cycloaliphatic rings, such as indolinyl, 3H-indolyl, chromanyl,
phenanthridinyl, or tetrahydroquinolinyl, where the radical or
point of attachment is on the heterocyclyl ring. A heterocyclyl
group may be mono- or bicyclic. The term "heterocyclylalkyl" refers
to an alkyl group substituted by a heterocyclyl, wherein the alkyl
and heterocyclyl portions independently are optionally
substituted.
[0042] As used herein, the term "partially unsaturated" refers to a
ring moiety that includes at least one double or triple bond. The
term "partially unsaturated" is intended to encompass rings having
multiple sites of unsaturation, but is not intended to include aryl
or heteroaryl moieties, as herein defined.
[0043] As described herein, compounds described herein may contain
"optionally substituted" moieties. In general, the term
"substituted", whether preceded by the term "optionally" or not,
means that one or more hydrogens of the designated moiety are
replaced with a suitable substituent. Unless otherwise indicated,
an "optionally substituted" group may have a suitable substituent
at each substitutable position of the group, and when more than one
position in any given structure may be substituted with more than
one substituent selected from a specified group, the substituent
may be either the same or different at every position. Combinations
of substituents envisioned are preferably those that result in the
formation of stable or chemically feasible compounds. The term
"stable", as used herein, refers to compounds that are not
substantially altered when subjected to conditions to allow for
their production, detection, and, in some embodiments, their
recovery, purification, and use for one or more of the purposes
disclosed herein.
[0044] In some chemical structures herein, substituents are shown
attached to a bond which crosses a bond in a ring of the depicted
molecule. This means that one or more of the substituents may be
attached to the ring at any available position (usually in place of
a hydrogen atom of the parent structure). In cases where an atom of
a ring so substituted has two substitutable positions, two groups
may be present on the same ring atom. When more than one
substituent is present, each is defined independently of the
others, and each may have a different structure. In cases where the
substituent shown crossing a bond of the ring is --R, this has the
same meaning as if the ring were said to be "optionally
substituted" as described in the preceding paragraph.
[0045] Suitable monovalent substituents on a substitutable carbon
atom of an "optionally substituted" group are independently
halogen; --(CH.sub.2).sub.0-4R.sup. ; --(CH.sub.2).sub.0-4OR.sup. ;
--O--(CH.sub.2).sub.0-4C(O)OR.sup. ; --(CH.sub.2).sub.0-4CH(OR.sup.
).sub.2; --(CH.sub.2).sub.0-4SR.sup. ; --(CH.sub.2).sub.0-4Ph,
which may be substituted with R.sup. ;
--(CH.sub.2).sub.0-4O(CH.sub.2).sub.0-1Ph which may be substituted
with R.sup. ; --CH.dbd.CHPh, which may be substituted with R.sup. ;
--NO.sub.2; --CN; --N.sub.3; --(CH.sub.2).sub.0-4N(R.sup. ).sub.2;
--(CH.sub.2).sub.0-4N(R.sup. )C(O)R.sup. ; --N(R.sup. )C(S)R.sup. ;
--(CH.sub.2).sub.0-4N(R.sup. )C(O)NR.sup. .sub.2; --N(R.sup.
)C(S)NR.sup. .sub.2; --(CH.sub.2).sub.0-4N(R.sup. )C(O)OR.sup. ;
--N(R.sup. )N(R.sup. )C(O)R.sup. ; --N(R.sup. )N(R.sup.
)C(O)NR.sup. .sub.2; --N(R.sup. )N(R.sup. )C(O)OR.sup. ;
--(CH.sub.2).sub.0-4C(O)R.sup. ; --C(S)R.sup. ;
--(CH.sub.2).sub.0-4C(O)OR.sup. ; --(CH.sub.2).sub.0-4C(O)N(R.sup.
).sub.2; --(CH.sub.2).sub.0-4C(O)SR.sup. ;
--(CH.sub.2).sub.0-4C(O)OSiR.sup. .sub.3;
--(CH.sub.2).sub.0-4OC(O)R.sup. ; --OC(O)(CH.sub.2).sub.0-4SR.sup.
; --SC(S)SR.sup. ; --(CH.sub.2).sub.0-4SC(O)R.sup. ;
--(CH.sub.2).sub.0-4C(O)NR.sup. .sub.2; --C(S)NR.sup. .sub.2;
--C(S)SR.sup. ; --SC(S)SR.sup. , --(CH.sub.2).sub.0-4OC(O)NR.sup.
.sub.2; --C(O)N(OR.sup. )R.sup. ; --C(O)C(O)R.sup. ;
--C(O)CH.sub.2C(O)R.sup. ; --C(NOR.sup. )R.sup. ;
--(CH.sub.2).sub.04SSR.sup. ; --(CH.sub.2).sub.04S(O).sub.2R.sup. ;
--(CH.sub.2).sub.0-4S(O).sub.2OR.sup. ;
--(CH.sub.2).sub.0-4OS(O).sub.2R.sup. ; --S(O).sub.2NR.sup. .sub.2;
--(CH.sub.2).sub.0-4S(O)R.sup. ; --N(R.sup. )S(O).sub.2NR.sup.
.sub.2; --N(R.sup. )S(O).sub.2R.sup. ; --N(OR.sup. )R.sup. ;
--C(NH)NR.sup. .sub.2; --P(O).sub.2R.sup. ; --P(O)R.sup. .sub.2;
--OP(O)R.sup. .sub.2; --OP(O)(OR.sup. ).sub.2; SiR.sup. .sub.3;
--(C.sub.1-4 straight or branched alkylene)O--N(R.sup. ).sub.2; or
--(C.sub.1-4 straight or branched alkylene)C(O)O--N(R.sup. ).sub.2,
wherein each R.sup. may be substituted as defined below and is
independently hydrogen, C.sub.1-8 aliphatic, --CH.sub.2Ph,
--O(CH.sub.2).sub.0-1Ph, or a 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, and sulfur, or, notwithstanding the
definition above, two independent occurrences of R.sup. , taken
together with their intervening atom(s), form a 3-12-membered
saturated, partially unsaturated, or aryl mono- or polycyclic ring
having 0-4 heteroatoms independently selected from nitrogen,
oxygen, and sulfur, which may be substituted as defined below.
[0046] Suitable monovalent substituents on R.sup. (or the ring
formed by taking two independent occurrences of R.sup. together
with their intervening atoms), are independently halogen,
--(CH.sub.2).sub.0-2R.sup..circle-solid.,
-(haloR.sup..circle-solid.), --(CH.sub.2).sub.0-2OH,
--(CH.sub.2).sub.0-2OR.sup..circle-solid.,
--(CH.sub.2).sub.0-2CH(OR.sup..circle-solid.).sub.2;
--O(haloR.sup..circle-solid.), --CN, --N.sub.3,
--(CH.sub.2).sub.0-2C(O)R.sup..circle-solid.,
--(CH.sub.2).sub.0-2C(O)OH,
--(CH.sub.2).sub.0-2C(O)OR.sup..circle-solid.,
--(CH.sub.2).sub.0-4C(O)N(R.sup. ).sub.2;
--(CH.sub.2).sub.0-2SR.sup..circle-solid., --(CH.sub.2).sub.0-2SH,
--(CH.sub.2).sub.0-2NH.sub.2,
--(CH.sub.2).sub.0-2NHR.sup..circle-solid.,
--(CH.sub.2).sub.0-2NR.sup..circle-solid..sub.2, --NO.sub.2,
--SiR.sup..circle-solid..sub.3, --OSiR.sup..circle-solid..sub.3,
--C(O)SR.sup..circle-solid.. --(C.sub.1-4 straight or branched
alkylene)C(O)OR.sup..circle-solid., or --SSR.sup..circle-solid.
wherein each R.sup..circle-solid. is unsubstituted or where
preceded by "halo" is substituted only with one or more halogens,
and is independently selected from C.sub.1-4 aliphatic,
--CH.sub.2Ph, --O(CH.sub.2).sub.0-1Ph, or a 5-6-membered saturated,
partially unsaturated, or aryl ring having 0-4 heteroatoms
independently selected from nitrogen, oxygen, and sulfur. Suitable
divalent substituents on a saturated carbon atom of R.sup. include
.dbd.O and .dbd.S,
[0047] Suitable divalent substituents on a saturated carbon atom of
an "optionally substituted" group include the following: .dbd.O,
.dbd.S, .dbd.NNR*.sub.2, .dbd.NNHC(O)R*, .dbd.NNHC(O)OR*,
.dbd.NNHS(O).sub.2R*, .dbd.NR*, .dbd.NOR*,
--O(C(R*.sub.2)).sub.2-3O--, or --S(C(R*.sub.2)).sub.2-3S--,
wherein each independent occurrence of R* is selected from
hydrogen, C.sub.1-6 aliphatic which may be substituted as defined
below, or an unsubstituted 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, and sulfur. Suitable divalent
substituents that are bound to vicinal substitutable carbons of an
"optionally substituted" group include: --O(CR*.sub.2).sub.2-3O--,
wherein each independent occurrence of R* is selected from
hydrogen, C.sub.1-6 aliphatic which may be substituted as defined
below, or an unsubstituted 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, and sulfur.
[0048] Suitable substituents on the aliphatic group of R* include
halogen, --R.sup..circle-solid., -(haloR.sup..circle-solid.), --OH,
--OR.sup..circle-solid., --O(haloR.sup..circle-solid.), --CN,
--C(O)OH, --C(O)OR.sup..circle-solid., --NH.sub.2,
--NHR.sup..circle-solid., --NR.sup..circle-solid..sub.2, or
--NO.sub.2, wherein each R.sup..circle-solid. is unsubstituted or
where preceded by "halo" is substituted only with one or more
halogens, and is independently C.sub.1-4 aliphatic, --CH.sub.2PH,
--O(CH.sub.2).sub.0-1Ph, or a 5-6membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, and sulfur.
[0049] Suitable substituents on a substitutable nitrogen of an
"optionally substituted" group include --R.sup..dagger.,
--NR.sup..dagger..sub.2, --C(O)R.sup..dagger.,
--C(O)OR.sup..dagger., --C(O)C(O)R.sup..dagger.,
--C(O)CH.sub.2C(O)R.sup..dagger., --S(O).sub.2R.sup..dagger.,
--S(O).sub.2NR.sup..dagger..sub.2, --C(S)NR.sup..dagger..sub.2,
--C(NH)NR.sup..dagger..sub.2, or
--N(R.sup..dagger.)S(O).sub.2R.sup..dagger.; wherein each
R.sup..dagger. is independently hydrogen, C.sub.1-6 aliphatic which
may be substituted as defined below, unsubstituted --OPh, or an
unsubstituted 5-6 -membered saturated, partially unsaturated, or
aryl ring having 0-4 heteroatoms independently selected from
nitrogen, oxygen, and sulfur, or, notwithstanding the definition
above, two independent occurrences of R.sup..dagger., taken
together with their intervening atom(s) form an unsubstituted
3-12membered saturated, partially unsaturated, or aryl mono- or
bicyclic ring having 0-4 heteroatoms independently selected from
nitrogen, oxygen, and sulfur.
[0050] Suitable substituents on the aliphatic group of
R.sup..dagger. are independently halogen, --R.sup..circle-solid.,
-(haloR.sup..circle-solid.), --OH, --OR.sup..circle-solid.,
--O(haloR.sup..circle-solid.), --CN, --C(O)OH,
--C(O)OR.sup..circle-solid., --NH.sub.2, --NHR.sup..circle-solid.,
--NR.sup..circle-solid..sub.2, or --NO.sub.2, wherein each
R.sup..circle-solid. is unsubstituted or where preceded by "halo"
is substituted only with one or more halogens, and is independently
C.sub.1-4 aliphatic, --CH.sub.2Ph, --O(CH.sub.2).sub.0-1Ph, or a
5-6-membered saturated, partially unsaturated, or aryl ring having
0-4 heteroatoms independently selected from nitrogen, oxygen, and
sulfur.
[0051] As used herein, the term "catalyst" refers to a substance
the presence of which increases the rate of a chemical reaction,
while not being consumed or undergoing a permanent chemical change
itself.
[0052] As used herein, the term "about" preceding one or more
numerical values means the numerical value .+-.5%. It should be
understood that reference to "about" a value or parameter herein
includes (and describes) embodiments that are directed to that
value or parameter per se. For example, description referring to
"about x" includes description of "x" per se.
DETAILED DESCRIPTION
[0053] Another route to produce acrylic acid from beta
propiolactone (BPL) first polymerizes BPL to poly(propiolactone)
(PPL), which is then isolated and fed into a pyrolysis unit where
it thermally decomposes to acrylic acid. The processes and systems
described herein provide a direct route for producing acrylic acid
from BPL, without isolation of the PPL intermediate. Thus, in one
aspect, provided is the direct conversion of BPL to glacial acrylic
acid (e.g., GAA) without isolation of PPL. In some embodiments,
provided is concurrent polymerization and pyrolysis steps to
directly convert BPL to acrylic acid (e.g., GAA) without isolation
of PPL. In certain embodiments, conversion of BPL to PPL is
performed in the presence of a polymerization catalyst. In some
embodiments, polymerization of BPL to PPL occurs first followed by
pyrolysis as part of a continuous process. By avoiding the need to
isolate, store, and/or transport PPL, the streamlined preparation
of acrylic acid (e.g., GAA) from BPL offers cost and manufacturing
efficiencies that were not previously obtainable.
[0054] In certain embodiments, provided are methods for the
conversion of BPL to acrylic acid product streams.
I. Methods
[0055] In one aspect, provided are integrated processes and methods
for the conversion of BPL to acrylic acid. In certain embodiments,
provided are integrated processes for the conversion of BPL to
acrylic acid in the presence of a polymerization catalyst without
the need to isolate PPL as a separate intermediate product.
[0056] In some embodiments, provided is a method for the synthesis
of acrylic acid comprising:
[0057] (a) providing a feedstock stream comprising beta
propiolactone;
[0058] (b) directing the feedstock stream to a reaction zone where
the feedstock stream is contacted with a polymerization catalyst
and where at least a portion of the beta propiolactone is converted
to poly(propiolactone);
[0059] (c) maintaining the action zone at a temperature at or above
the pyrolysis temperature of poly(propiolactone) such that the
thermal decomposition of poly(propiolactone) produces acrylic acid;
and
[0060] (d) withdrawing an acrylic acid product stream from the
reaction zone;
[0061] wherein steps (b) and (c) occur in the same reaction
zone.
[0062] In some embodiments, provided is a method for the synthesis
of acrylic acid comprising:
[0063] (a) providing a feedstock stream comprising beta
propiolactone;
[0064] (b) directing the feedstock stream to a first reaction zone
where the feedstock stream is contacted with a polymerization
catalyst and where at least a portion of the beta propiolactone is
converted to a poly(propiolactone) product stream, wherein the
first reaction zone is maintained at a temperature suitable for the
formation of poly(propiolactone);
[0065] (c) directing the poly(propiolactone) product stream to a
second reaction zone, wherein the second reaction zone is
maintained at a temperature at or above the pyrolysis temperature
of poly(propiolactone) such that the thermal decomposition of
poly(propiolactone) produces acrylic acid; and
[0066] (d) withdrawing an acrylic acid product stream from the
second reaction zone.
[0067] It should generally be understood that reference to "a first
reaction zone" or "a second reaction zone", etc. does not
necessarily imply an order of the reaction zones. In some
variations, the use of such references denotes the number of
reaction zones present. In other variations, an order may be
implied by the context in which the reaction zones are configured,
used or present.
[0068] In some variations of the foregoing aspects and embodiments,
the polymerization catalyst is a carboxylate catalyst.
[0069] In some embodiments, provided method for producing acrylic
acid, comprising:
[0070] (a) providing a feedstock stream comprising beta
propiolactone;
[0071] (b) directing the feedstock stream to a reaction zone;
[0072] (c) contacting the feedstock stream with a polymerization
catalyst in the reaction zone;
[0073] (d) converting at least a portion of the beta propiolactone
to poly(propiolactone) in the reaction zone;
[0074] (e) maintaining the reaction zone at a temperature at or
above the pyrolysis temperature of poly(propiolactone) such that
the thermal decomposition of poly(propiolactone) produces acrylic
acid; and
[0075] (f) withdrawing an acrylic acid product stream from the
reaction zone;
[0076] wherein steps (b) and (e) occur in the same reaction
zone.
[0077] In one embodiment, provided is a method for producing
acrylic acid, comprising:
[0078] (a) providing a feedstock stream comprising beta
propiolactone;
[0079] (b) directing the feedstock stream to a reaction zone;
[0080] (c) contacting the feedstock stream with a polymerization
catalyst in the reaction zone;
[0081] (d) polymerizing at least a portion of the beta
propiolactone to poly(propiolactone) in the reaction zone, wherein
the temperature of the reaction zone is at or above the pyrolysis
temperature of poly(propiolactone);
[0082] (e) thermally decomposing the poly(propiolactone) in the
reaction zone to produce acrylic acid; and
[0083] (f) withdrawing an acrylic acid product stream comprising
the acrylic acid from the reaction zone;
[0084] wherein steps (b) and (e) occur in the same reaction
zone.
[0085] In the embodiment described above, the production of the
poly(propiolactone) and the thermal decomposition of the
poly(propiolactone) produced occurs simultaneously in the reaction
zone.
[0086] The sections below describe more fully certain embodiments
of the steps of the methods and conditions utilized to effect each
step.
BPL Conversion to PPL
[0087] A beta-lactone feedstock stream used in accordance with
provided methods and systems may be provided from any one or more
of a number of known sources of BPL. Methods of making BPL are
known in the art and include those described in WO2013/063191 and
WO2014/004858. In some embodiments, a feedstock stream comprising
BPL enters a reaction zone described herein as a gas or as a
liquid. The conversion of BPL to PPL may be performed in either the
gas phase or the liquid phase and may be performed neat, or in the
presence of a carrier gas, solvent, or other diluent. In some
embodiments, a BPL feedstock stream is neat.
[0088] It will be appreciated that in certain embodiments, the
methods and systems described herein can also be directly
integrated to the formation of ethylene oxide, thus avoiding the
isolation and storage of this toxic and potentially explosive
intermediate. In certain embodiments, the processes described
herein are fed by ethylene gas which is converted to ethylene
oxide, the ethylene oxide then feeds a second reaction where
carbonylation takes place to yield a feedstock stream comprising
BPL.
[0089] In certain embodiments, conversion of BPL to PPL is
performed in a continuous flow format. In certain embodiments,
conversion of BPL to PPL is performed in a continuous flow format
in the gas phase. In certain embodiments, conversion of BPL to PPL
is performed in a continuous flow format in the liquid phase. In
certain embodiments, conversion of BPL to PPL is performed in a
liquid phase in a batch or semi-batch format. Conversion of BPL to
PPL may be performed under a variety of conditions. In certain
embodiments, the reaction may be performed in the presence of one
or more polymerization catalysts that facilitate the transformation
of the BPL to PPL. In one embodiment, the reaction may be performed
in the presence of one or more carboxylate catalysts that
facilitate the transformation of the BPL to PPL.
[0090] In certain embodiments, a feedstock stream comprising BPL is
directed to a reaction zone where it is contacted with a
polymerization catalyst and where at least a portion of the BPL is
converted to PPL. In one embodiment, a feedstock stream comprising
BPL is directed to a reaction zone where it is contacted with a
carboxylate catalyst and where at least a portion of the BPL is
converted to PPL. In some embodiments, the reaction zone is
maintained at a temperature suitable for the formation of PPL. In
some embodiments, such temperature maintenance comprises the
removal of heat from the reaction zone.
[0091] In some embodiments, a feedstock stream comprising BPL is
directed to a first reaction zone where it is contacted with a
polymerization catalyst and where at least a portion of the BPL is
converted to a PPL product stream. In one embodiment, a feedstock
stream comprising BPL is directed to a first reaction zone where it
is contacted with a carboxylate catalyst and where at least a
portion of the BPL is converted to a PPL product stream. In some
embodiments, the first reaction zone is maintained at a temperature
suitable for the formation of PPL. In some embodiments, such
temperature maintenance comprises the removal of heat from the
first reaction zone.
[0092] In certain embodiments, conversion of BPL to PPL utilizes a
solid polymerization catalyst and the conversion is conducted at
least partially in the gas phase. In certain embodiments, the solid
polymerization catalyst in the beta lactone conversion stage
comprises a solid acrylic acid catalyst. In certain embodiments,
BPL is introduced as a liquid and contacted with a solid
polymerization catalyst to form PPL, which undergoes pyrolysis and
acrylic acid is removed as a gaseous stream. In other embodiments,
BPL is introduced as a gas, contacted with a solid polymerization
catalyst to form PPL, which undergoes pyrolysis and acrylic acid is
removed as a gaseous stream.
[0093] In some variations, conversion of BPL to PPL utilizes a
solid carboxylate catalyst and the conversion is conducted at least
partially in the gas phase. In certain embodiments, the solid
carboxylate catalyst in the beta lactone conversion stage comprises
a solid acrylic acid catalyst. In certain embodiments, BPL is
introduced as a liquid and contacted with a solid carboxylate
catalyst to form PPL, which undergoes pyrolysis and acrylic acid is
removed as a gaseous stream. In other embodiments, BPL is
introduced as a gas, contacted with a solid carboxylate catalyst to
form PPL, which undergoes pyrolysis and acrylic acid is removed as
a gaseous stream.
[0094] In certain embodiments, processes described herein are
characterized in that the feed rates, reaction rates, and reactor
sizes are scaled such that each subsequent stage in the process
cart utilize essentially all of the effluent from the previous
stage. In certain embodiments, methods include one or more steps of
modulating one or more system parameters selected from the group
consisting of: the temperature and/or pressure of the lactone
conversion stage, the temperature and/or pressure of the pyrolysis
stage, and a combination of any two or more of these parameters. In
certain embodiments, this modulation of system parameters is
performed such that the conversion rate per unit time of each stage
matches that of the previous stage so that the effluent of the
previous stage may be used directly to feed the subsequent stage.
In certain embodiments, methods include one or more steps of
analyzing the effluent from one or more stages to assess its
content. In certain embodiments, such analyzing steps include
performing spectroscopy (e.g., infrared spectroscopy, nuclear
magnetic resonance spectroscopy, ultraviolet or visible light
spectroscopy and the like), chromatography (e.g., gas or liquid
chromatography). In certain embodiments, such analyzing steps
include performing physical analyses (e.g., viscosity measurements,
refractive index measurement, density measurement of conductivity
measurement). In certain embodiments, such analyses are performed
in a flow-through or stop-flow mode that provides real-time data on
the chemical composition of the effluent. In certain embodiments,
such data are used to provide a prompt to adjust one or more of the
system parameters described above.
[0095] As described above, in some embodiments a two-step process
is utilized where at least a portion of BPL is converted to a PPL
product stream in a first reaction zone, wherein the first reaction
zone is maintained at a temperature suitable for the formation of
PPL. In some embodiments, the temperature of a first reaction zone
is maintained at or below the pyrolysis temperature of
polypropiolactone. In some embodiments, the temperature of a first
reaction zone is maintained at or below about 150.degree. C. In
some embodiments, the temperature of a first reaction zone is
maintained at about 0.degree. C. to about 150.degree. C. In some
embodiments, the temperature of a first reaction zone is maintained
at about 25.degree. C. to about 150.degree. C. In some embodiments,
the temperature of a first reaction zone is maintained at about
50.degree. C. to about 150.degree. C. In some embodiments, the
temperature of a first reaction zone is maintained at about
75.degree. C. to about 150.degree. C. In some embodiments, the
temperature of a first reaction zone is maintained at about
100.degree. C. to about 150.degree. C. In some embodiments, the
temperature of a first reaction zone is maintained at about
0.degree. C. to about 100.degree. C. In some embodiments, the
temperature of a first reaction zone is maintained at about
50.degree. C. to about 100.degree. C.
PPL Pyrolysis
[0096] As described above, in one aspect, BPL is converted to GAA
without isolation of the intermediate PPL. In some embodiments, the
PPL formed by polymerization of BPL is concurrently converted to
acrylic acid (e.g., GAA) via pyrolysis in the same reaction zone
(e.g., a "one-pot" method). In some embodiments, the reaction zone
containing the reaction of BPL to PPL is maintained at a
temperature at or above the pyrolysis temperature of PPL such that
the thermal decomposition of PPL produces acrylic acid. Without
wishing to be bound by any particular theory, it is believed that
in such embodiments as BPL reacts with acrylic acid to start
polymer chains, thermal decomposition will degrade the polymer to
acrylic acid.
[0097] In certain embodiments, a PPL product stream described above
as forming a first reaction zone is directed to a second reaction
zone, wherein the second reaction zone is maintained at a
temperature at or above the pyrolysis temperature of PPL such that
the thermal decomposition of PPL produces acrylic acid. In some
embodiments, the temperature of a first reaction zone is different
than the temperature of a second reaction zone. In some
embodiments, the temperature of a first reaction zone is below the
pyrolysis temperature of PPL. Such embodiments may also be
described as a "two-step" method, wherein at least a portion of BPL
converted to PPL prior to entering a reaction zone maintained at or
above the pyrolysis temperature. In some embodiments, the PPL
product stream entering a second reaction zone comprises an amount
of unreacted BPL. In other words, the formation of PPL need not be
complete prior to a PPL product stream entering a second reaction
zone, and in such cases BPL may undergo polymerization to PPL
followed by pyrolysis within the second reaction zone.
[0098] A one-pot BPL conversion to acrylic acid can be operated
within a variety of temperature and pressure ranges. In some
embodiments, the temperature can range from about 150.degree. C. to
about 400.degree. C. In some embodiments, the temperature ranges
from about 150.degree. C. to about 300.degree. C. In some
embodiments, the temperature ranges from about 150.degree. C. to
about 250.degree. C. In some embodiments, the temperature ranges
from about 175.degree. C. to about 300.degree. C. In some
embodiments, the temperature ranges from about 200.degree. C. to
about 250.degree. C. In some embodiments, the temperature ranges
from about 225.degree. C. to about 275.degree. C. In some
embodiments, the temperature ranges from about 250.degree. C. to
about 300.degree. C. In some embodiments, the temperature ranges
from about 200.degree. C. to about 300.degree. C.
[0099] In some embodiments, a two-step process is utilized where
pyrolysis proceeds in a second reaction zone and the second
reaction zone is maintained at a temperature at or above the
pyrolysis temperature of poly(propiolactone). In some embodiments,
the temperature of a second reaction zone is maintained at or above
about 150.degree. C. In some embodiments, the temperature of a
second reaction zone is maintained at or above about 160.degree. C.
In some embodiments, the temperature of a second reaction zone is
maintained at or above about 175.degree. C. In some embodiments,
the temperature of a second reaction zone is maintained at or above
about 200.degree. C. In some embodiments, the temperature of a
second reaction zone is maintained at or above about 225.degree. C.
In some embodiments, the temperature of a second reaction zone is
maintained at or above about 250.degree. C. In some embodiments,
the temperature of a second reaction zone is maintained at or above
about 275.degree. C.
[0100] In some embodiments, the pressure used in provided methods
and systems can range from about 0.01 atmospheres to about 500
atmospheres (absolute). In some embodiments, the pressure can range
from about 0.01 atmospheres to about 10 atmospheres (absolute). In
some embodiments, the pressure can range from about 0.01
atmospheres to about 50 atmospheres (absolute). In some
embodiments, the pressure can range from about 1 atmosphere to
about 10 atmospheres (absolute). In some embodiments, the pressure
can range from about 1 atmosphere to about 50 atmospheres
(absolute). In some embodiments, the pressure can range from about
1 atmosphere to about 100 atmospheres (absolute). In some
embodiments, the pressure can range from about 10 atmospheres to
about 50 atmospheres (absolute). In some embodiments, the pressure
can range from about 10 atmospheres to about 100 atmospheres
(absolute). In some embodiments, the pressure can range from about
50 atmospheres to about 100 atmospheres (absolute). In some
embodiments, the pressure can range from about 50 atmospheres to
about 200 atmospheres (absolute). In some embodiments, the pressure
can range from about 100 atmospheres to about 200 atmospheres
(absolute). In some embodiments, the pressure can range from about
100 atmospheres to about 250 atmospheres (absolute). In some
embodiments, the pressure can range from about 200 atmospheres to
about 300 atmospheres (absolute). In some embodiments, the pressure
can range from about 200 atmospheres to about 500 atmospheres
(absolute). In some embodiments, the pressure can range from about
250 atmospheres to about 500 atmospheres (absolute).
[0101] In some embodiments, the pressure used in provided methods
and systems is less than about 5 atmospheres (absolute). In some
embodiments, the pressure used in provided methods and systems is
less than about 1 atmosphere (absolute). In some embodiments, the
pressure can range from about 0.01 atmospheres to about 1
atmosphere (absolute). In some embodiments, the pressure can range
from about 0.1 atmospheres to about 0.8 atmospheres (absolute). In
some embodiments, the pressure can range from about 0.1 atmospheres
to about 0.5 atmospheres (absolute). In some embodiments, the
pressure can range from about 0.01 atmospheres to about 0.1
atmospheres (absolute). In some embodiments, the pressure can range
from about 0.4 atmospheres to about 1 atmosphere (absolute). In
some embodiments, the pressure can range from about 0.05
atmospheres to about 0.1 atmospheres (absolute).
[0102] In embodiments where there are two reaction zones, they need
not be operated at the same pressure. In certain embodiments the
first reaction zone is operated at atmospheric or superatmospheric
pressures while the second reaction zone is operated at
subatmospheric pressure. In certain embodiments a reaction zone can
include a pressure gradient.
Reaction Zones
[0103] As used herein, the term "reaction zone" refers to a reactor
or portion thereof where a particular reaction occurs. A given
reaction may occur in multiple reaction zones, and different
reaction zones may comprise separate reactors or portions of the
same reactor. A "reactor" typically comprises one or more vessels
with one or more connections to other reactors or system
components.
[0104] In some embodiments of provided methods and systems, a first
reaction zone and second reaction zone are comprised within an
extruder reactor. In some embodiments, an extruder reactor provides
a temperature gradient between a first reaction zone and second
reaction zone. It will be appreciated that the temperature of a
first reaction zone can be lower than that of a second reaction
zone due to the relative temperatures needed to carry out each
reaction therein. In some embodiments, an extruder reactor provides
a temperature in a first reaction zone of about 0.degree. C. to
about 150.degree. C., and a temperature in a second reaction zone
of about 150.degree. C. to about 300.degree. C. In some
embodiments, the terminal temperature of an extruder is at or above
the pyrolysis temperature of PPL. In some variations, terminal
temperature refers to the temperature at the exit of the
extruder.
Polymerization Catalysts
[0105] As described above, polymerizing the BPL to PPL proceeds in
the presence of a polymerization catalyst. A variety of catalysts
may be used in the polymerization reaction, including by not
limited to metals (e.g., lithium, sodium, potassium, magnesium,
calcium, zinc, aluminum, titanium, cobalt, etc.) metal oxides,
salts of alkali and alkaline earth metals (such as carbonates,
borates, hydroxides, alkoxides, and carboxylates), and borates,
silicates, or salts of other metals. In certain embodiments,
suitable catalysts include carboxylate salts of metal ions. In
certain embodiments suitable catalysts include carboxylate salts of
organic cations. In some embodiments, a carboxylate salt is other
than a carbonate. In some embodiments, a carboxylate salt is
acrylate.
[0106] In certain embodiments, the polymerization catalyst is
combined with BPL in a molar ratio up to about 1:100,000
polymerization catalyst:BPL. In certain embodiments, the ratio is
from about 1:100,000 to about 25:100 polymerization catalyst:BPL.
In certain embodiments, the polymerization catalyst is combined
with BPL in a molar ratio of about 1:50,000 polymerization
catalyst:BPL to about 1:25,000 polymerization catalyst:BPL. In
certain embodiments, the polymerization catalyst is combined with
BPL in a molar ratio of about 1:25,000 polymerization catalyst:BPL
to about 1:10,000 polymerization catalyst:BPL. In certain
embodiments, the polymerization catalyst is combined with BPL in a
molar ratio of about 1:20,000 polymerization catalyst:BPL to about
1:10,000 polymerization catalyst:BPL. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:15,000 polymerization catalyst:BPL to about 1:5,000
polymerization catalyst:BPL. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:5,000 polymerization catalyst:BPL to about 1:1,000
polymerization catalyst:BPL. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:2,000 polymerization catalyst:BPL to about 1:500
polymerization catalyst:BPL. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:1,000 polymerization catalyst:BPL to about 1:200
polymerization catalyst:BPL. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:500 polymerization catalyst:BPL to about 1:100
polymerization catalyst:BPL. In certain embodiments the molar ratio
of polymerization catalyst:BPL is about 1:50,000, 1:25,000,
1:15,000, 1:10,000, 1:5,000, 1:1,000, 1:500, 1:250 or a range
including any two of these values. In certain embodiments, the
polymerization catalyst is combined with BPL in a molar ratio of
about 1:100 polymerization catalyst:BPL to about 25:100
polymerization catalyst:BPL. In certain embodiments the molar ratio
of polymerization catalyst:BPL is about 1:100, 5:100, 10:100,
15:100, 20:100, 25:100, or a range including any two of these
ratios.
[0107] In certain embodiments, where the polymerization catalyst
comprises a carboxylate salt, the carboxylate has a structure such
that upon initiating polymerization of BPL, the polymer chains
produced have an acrylate chain end. In certain embodiments, the
carboxylate ion on a polymerization catalyst is the anionic form of
a chain transfer agent used in the polymerization process.
[0108] In certain embodiments, the carboxylate salt of the
polymerization catalyst is an acrylate salt (i.e., the anionic
form) of a compound of Formula (I):
##STR00001##
or a mixture of any two or more of these, where p is from 0 to 9.
In certain embodiments, p is from 0 to 5. In certain embodiments,
the carboxylate salt of the polymerization catalyst is an acrylate
salt (i.e., of compound of Formula (I) where p=0).
[0109] In certain embodiments, the carboxylate salt of the
polymerization catalyst is a salt of an acrylic acid dimer,
##STR00002##
In certain embodiments, the carboxylate salt of the polymerization
catalyst is a salt of an acrylic acid trimer,
##STR00003##
[0110] In certain embodiments, where the polymerization catalyst
comprises a carboxylate salt, the carboxylate is the anionic form
of a C.sub.1-40 carboxylic acid. In certain embodiments, the
carboxylate salt can be a salt of a polycarboxylic acid (e.g. a
compound having two or more carboxylic acid groups). In certain
embodiments, the carboxylate comprises the anion of a C.sub.1-20
carboxylic acid. In certain embodiments, the carboxylate comprises
the anion of a C.sub.1-12 carboxylic acid. In certain embodiments,
the carboxylate comprises the anion of a C.sub.1-8 carboxylic acid.
In certain embodiments, the carboxylate comprises the anion of a
C.sub.1-4 carboxylic acid. In certain embodiments, the carboxylate
comprises the anion of an optionally substituted benzoic acid. In
certain embodiments, the carboxylate is selected from the group
consisting of: formate, acetate, propionate, valerate, butyrate,
C.sub.5-10 aliphatic carboxylate, and C.sub.10-20 aliphatic
carboxylate.
[0111] As noted, in certain embodiments, the polymerization
catalyst comprises a carboxylate salt of an organic cation. In
certain embodiments, the polymerization catalyst comprises a
carboxylate salt of a cation wherein the positive charge is located
at least partially on a nitrogen, sulfur, or phosphorus atom. In
certain embodiments, the polymerization catalyst comprises a
carboxylate salt of a nitrogen cation. In certain embodiments, the
polymerization catalyst comprises a carboxylate salt of a cation
selected from the group consisting of: ammonium, amidinium,
guanidinium, a cationic form of a nitrogen heterocycle, and any
combination of two or more of these. In certain embodiments, the
polymerization catalyst comprises a carboxylate salt of a
phosphorus cation. In certain embodiments, the polymerization
catalyst comprises a carboxylate salt of a cation selected from the
group consisting of: phosphonium and phosphazenium. In certain
embodiments, the polymerization catalyst comprises a carboxylate
salt of a sulfur-containing cation. In certain embodiments, the
polymerization catalyst comprises a sulfonium salt.
[0112] In certain embodiments, the polymerization catalyst
comprises a carboxylate salt of a metal. In certain embodiments,
the polymerization catalyst comprises a carboxylate salt of a
alkali or alkaline earth metal. In certain embodiments, the
polymerization catalyst comprises a carboxylate salt of an alkali
metal. In certain embodiments, the polymerization catalyst
comprises a carboxylate salt of sodium or potassium. In certain
embodiments, the polymerization catalyst comprises a carboxylate
salt of sodium.
[0113] In certain embodiments, the polymerization catalyst
comprises a carboxylate salt of a protonated amine:
##STR00004##
where:
[0114] each R.sup.1 and R.sup.2 is independently hydrogen or an
optionally substituted radical selected from the group consisting
of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to
8-membered saturated or partially unsaturated monocyclic
carbocycle; a 7- to 14-membered saturated or partially unsaturated
polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl
ring having 1-4 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring
having 1-5 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; a 3- to 8-membered saturated or partially
unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms
independently selected from nitrogen, oxygen, or sulfur; a 6- to
14-membered saturated or partially unsaturated polycyclic
heterocycle having 1-5 heteroatoms independently selected from
nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered
polycyclic aryl ring; wherein R.sup.1 and R.sup.2 can be taken
together with intervening atoms to form one or more optionally
substituted rings optionally containing one or more additional
heteroatoms;
[0115] each R.sup.3 is independently hydrogen or an optionally
substituted radical selected from the group consisting of
C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to
8-membered saturated or partially unsaturated monocyclic
carbocycle; a 7- to 14-membered saturated or partially unsaturated
polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl
ring having 1-4 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring
having 1-5 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; a 3- to 8-membered saturated or partially
unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms
independently selected from nitrogen, oxygen, or sulfur; a 6- to
14-membered saturated or partially unsaturated polycyclic
heterocycle having 1-5 heteroatoms independently selected from
nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered
polycyclic aryl ring; wherein an R.sup.3 group can be taken with an
R.sup.1 or R.sup.2 group to form one or more optionally substituted
rings.
[0116] In certain embodiments where the polymerization catalyst
comprises a carboxylate salt of a protonated amine, the protonated
amine is selected from the group consisting of:
##STR00005##
[0117] In certain embodiments, the polymerization catalyst
comprises a carboxylate salt of a quaternary ammonium salt:
##STR00006##
where: [0118] each R.sup.1, R.sup.2 and R.sup.3 is described above;
and [0119] each R.sup.4 is independently hydrogen or an optionally
substituted radical selected from the group consisting of
C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to
8-membered saturated or partially unsaturated monocyclic
carbocycle; a 7- to 14-membered saturated or partially unsaturated
polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl
ring having 1-4 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring
having 1-5 heteroatoms independently selected from nitrogen,
oxygen, or sulfur; a 3- to 8-membered saturated or partially
unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms
independently selected from nitrogen, oxygen, or sulfur; a 6- to
14-membered saturated or partially unsaturated polycyclic
heterocycle having 1-5 heteroatoms independently selected from
nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered
polycyclic aryl ring; wherein an R.sup.4 group can be taken with an
R.sup.1, R.sup.2 or R.sup.3 group to form one or more optionally
substituted rings.
[0120] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of a guanidinium group:
##STR00007##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein. In certain
embodiments, each R.sup.1 and R.sup.2 is independently hydrogen or
C.sub.1-20 aliphatic. In certain embodiments, each R.sup.1 and
R.sup.2 is independently hydrogen or C.sub.1-12 aliphatic. In
certain embodiments, each R.sup.1 and R.sup.2 is independently
hydrogen or C.sub.1-20 heteroaliphatic. In certain embodiments,
each R.sup.1 and R.sup.2 is independently hydrogen or phenyl. In
certain embodiments, each R.sup.1 and R.sup.2 is independently
hydrogen or 8- to 10-membered aryl. In certain embodiments, each
R.sup.1 and R.sup.2 is independently hydrogen or 5- to 10-membered
heteroaryl. In certain embodiments, each R.sup.1 and R.sup.2 is
independently hydrogen or 3- to 7-membered heterocyclic. In certain
embodiments, one or more of R.sup.1 and R.sup.2 is optionally
substituted C.sub.1-12 aliphatic.
[0121] In certain embodiments, any two or more R.sup.1 or R.sup.2
groups are taken together with intervening atoms to form one or
more optionally substituted carbocyclic, heterocyclic, aryl, or
heteroaryl rings. In certain embodiments, R.sup.1 and R.sup.2
groups are taken together to form an optionally substituted 5- or
6-membered ring. In certain embodiments, three or more R.sup.1
and/or R.sup.2 groups are taken together to form an optionally
substituted fused ring system.
[0122] In certain embodiments, an R.sup.1 and R.sup.2 group are
taken together with intervening atoms to form a compound selected
from:
##STR00008##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein, and Ring G is an
optionally substituted 5- to 7-membered saturated or partially
unsaturated heterocyclic ring.
[0123] It will be appreciated that when a guanidinium cation is
depicted as
##STR00009##
all such resonance forms are contemplated and encompassed by the
present disclosure. For example, such groups can also be depicted
as
##STR00010##
[0124] In specific embodiments, a guanidinium cation is selected
from the group consisting of:
##STR00011##
[0125] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of a sulfonium group or an arsonium group:
##STR00012##
wherein each of R.sup.1, R.sup.2, and R.sup.3 are as defined above
and described in classes and subclasses herein.
[0126] In specific embodiments, an arsonium cation is selected from
the group consisting of:
##STR00013##
[0127] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of an optionally substituted nitrogen-containing
heterocycle. In certain embodiments, the nitrogen-containing
heterocycle is an aromatic heterocycle. In certain embodiments, the
optionally substituted nitrogen-containing heterocycle is selected
from the group consisting of: pyridine, imidazole, pyrrolidine,
pyrazole, quinoline, thiazole, dithiazole, oxazole, triazole,
pyrazolem, isoxazole, isothiazole, tetrazole, pyrazine, thiazine,
and triazine.
[0128] In certain embodiments, a nitrogen-containing heterocycle
includes a quaternarized nitrogen atom. In certain embodiments, a
nitrogen-containing heterocycle includes an iminium moiety such
as
##STR00014##
In certain embodiments, the optionally substituted
nitrogen-containing heterocycle is selected from the group
consisting of pyridinium, imidazolium, pyrrolidinium, pyrazolium,
thiazolium, dithiazolium, oxazolium, triazolium, isoxazolium,
isothiazolium, tetrazolium, pyrazinium, thiazinium, and
triazinium.
[0129] In certain embodiments, a nitrogen-containing heterocycle is
linked to a metal complex via a ring nitrogen atom. In certain
embodiments, a ring nitrogen to which the attachment is made is
thereby quaternized, and In certain embodiments, linkage to a metal
complex takes the place of an N--H bond and the nitrogen atom
thereby remains neutral. In certain embodiments, an optionally
substituted N-linked nitrogen-containing heterocycle is a
pyridinium derivative. In certain embodiments, optionally
substituted N-linked nitrogen-containing heterocycle is an
imidazolium derivative. In certain embodiments, optionally
substituted N-linked nitrogen-containing heterocycle is a
thiazolium derivative. In certain embodiments, optionally
substituted N-linked nitrogen-containing heterocycle is a
pyridinium derivative.
[0130] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00015##
In certain embodiments, ring A is an optionally substituted, 5- to
10-membered heteroaryl group. In certain embodiments, Ring A is an
optionally substituted, 6-membered heteroaryl group. In certain
embodiments, Ring A is a ring of a fused heterocycle. In certain
embodiments, Ring A is an optionally substituted pyridyl group.
[0131] In specific embodiments, a nitrogen-containing heterocyclic
cation is selected from the group consisting of:
##STR00016## ##STR00017##
[0132] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00018##
where each R.sup.1, R.sup.2, and R.sup.3 is independently as
defined above and described in classes and subclasses herein.
[0133] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00019##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein.
[0134] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00020##
wherein each R.sup.1, R.sup.2, and R.sup.3 is independently defined
above and described in classes and subclasses herein.
[0135] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00021##
wherein each of R.sup.1, R.sup.2, R.sup.6, and R.sup.7 is as
defined above and described in classes and subclasses herein.
[0136] In certain embodiments, R.sup.6 and R.sup.7 are each
independently an optionally substituted group selected from the
group consisting of C.sub.1-20 aliphatic; C.sub.1-20
heteroaliphatic; phenyl, and 8-10-membered aryl. In certain
embodiments, R.sup.6 and R.sup.7 are each independently an
optionally substituted C.sub.1-20 aliphatic. In certain
embodiments, R.sup.6 and R.sup.7 are each independently an
optionally substituted C.sub.1-20 heteroaliphatic having. In
certain embodiments, R.sup.6 and R.sup.7 are each independently an
optionally substituted phenyl or 8-10-membered aryl. In certain
embodiments, R.sup.6 and R.sup.7 are each independently an
optionally substituted 5- to 10-membered heteroaryl. In certain
embodiments, R.sup.6 and R.sup.7 can be taken together with
intervening atoms to form one or more rings selected from the group
consisting of: optionally substituted C.sub.3-C.sub.14 carbocycle,
optionally substituted C.sub.3-C.sub.14 heterocycle, optionally
substituted C.sub.6-C.sub.10 aryl, and optionally substituted 5- to
10-membered heteroaryl. In certain embodiments, R.sup.6 and R.sup.7
are each independently an optionally substituted C.sub.1-6
aliphatic. In certain embodiments, each occurrence of R.sup.6 and
R.sup.7 is independently methyl, ethyl, propyl, butyl, pentyl,
hexyl, heptyl, octyl, or benzyl. In certain embodiments, each
occurrence of R.sup.6 and R.sup.7 is independently perfluoro. In
certain embodiments, each occurrence of R.sup.6 and R.sup.7 is
independently --CF.sub.2CF.sub.3.
[0137] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00022##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein.
[0138] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00023##
wherein each R.sup.1, R.sup.2, and R.sup.3 is independently as
defined above and described in classes and subclasses herein.
[0139] In certain embodiments, a cation is
##STR00024##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein.
[0140] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00025##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein.
[0141] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00026##
wherein each R.sup.1, R.sup.2, and R.sup.3 is independently as
defined above and described in classes and subclasses herein.
[0142] In certain embodiments, a polymerization catalyst comprises
a carboxylate salt of
##STR00027##
wherein each R.sup.1 and R.sup.2 is independently as defined above
and described in classes and subclasses herein. In certain
embodiments, suitable catalysts include transition metal compounds.
In certain embodiments, suitable catalysts include acid catalysts.
In certain embodiments, the catalyst is a heterogeneous
catalyst.
[0143] In certain embodiments, any of the foregoing cationic
functional groups are attached to a solid support. Examples of
suitable solid supports include polymeric solids (e.g. polymer
beads, films, fibers, fabric, particles and the like) as well as
inorganic solids (e.g. clays, silicas, aluminas, diatomaceous
earth, ceramics, metal oxides, mineral fibers beads or particles,
and the like). Specific examples of such supported cationic
functional groups include polystyrene resin beads functionalized
with ammonium groups, polystyrene resin beads functionalized with
phosphonium groups, and polystyrene resin beads functionalized with
guanidinium groups. Specific examples of such supported cationic
functional groups include silica particles functionalized with
ammonium groups, alumina particles functionalized with phosphonium
groups, and ceramic beads functionalized with guanidinium groups.
In certain embodiments, polymerization catalysts comprise
carboxylate salts of any of the foregoing supported solid cationic
functional groups. In certain embodiments, polymerization catalysts
comprise acrylate salts of any of the foregoing supported solid
cationic functional groups.
[0144] In certain embodiments, polymerization catalysts comprise
cationic solids wherein the cations comprise metal atoms. In
certain embodiments, polymerization catalysts comprise carboxylate
salts of any of the foregoing supported solid cationic metal atoms.
In certain embodiments, polymerization catalysts comprise acrylate
salts of any of the foregoing supported solid cationic metal
atoms.
[0145] In certain embodiments, the carboxylate salt of the
polymerization catalyst is a compound of Formula (II):
##STR00028##
[0146] where p is from 0 to 9 and R.sup.a is a non-volatile moiety.
The term "non-volatile moiety," as used herein, refers to a moiety
or material to which a carboxylate can be attached, and that
renders the carboxylate (e.g., when p=0) non-volatile to pyrolysis
conditions. In some embodiments, a non-volatile moiety is selected
from the group consisting of glass surfaces, silica surfaces,
plastic surfaces, metal surfaces including zeolites, surfaces
containing a metallic or chemical coating, membranes (e.g., nylon,
polysulfone, silica), micro-beads (e.g., latex, polystyrene, or
other polymer), and porous polymer matrices (e.g., polyacrylamide,
polysaccharide, polymethacrylate). In some embodiments, a
non-volatile moiety has a molecular weight above 100, 200, 500, or
1000 g/mol. In some embodiments, a non-volatile moiety is part of a
fixed or packed bed system. In some embodiments, a non-volatile
moiety is part of a fixed or packed bed system comprising pellets
(e.g., zeolite).
[0147] In certain embodiments, p is from 0 to 5. In certain
embodiments, the carboxylate salt of the polymerization catalyst is
an acrylate salt (i.e., of compound of Formula (II) where p=0).
[0148] In some embodiments, a suitable polymerization catalyst is
heterogeneous. In some embodiments, a suitable polymerization
catalyst will remain in a reaction zone as a salt or melt after
removal of all other products, intermediates, starting materials,
byproducts, and other reaction components. In some embodiments, a
suitable polymerization catalyst of Formula (II) will remain in a
reaction zone as a salt or melt after removal of all acrylic acid
product stream.
[0149] In certain embodiments, a catalyst is recycled for further
use in a reaction zone. In some embodiments, a salt or melt
catalyst is recycled to a reaction zone. In some embodiments,
provided methods further comprise withdrawing a recycling stream of
homogeneous catalyst front a reaction zone. In some embodiments,
such a recycling stream comprises a high boiling solvent, wherein
the solvent's boiling point is above the pyrolysis temperature of
PPL and the catalyst remains in the high boiling solvent during
pyrolysis while the withdrawn product stream is gaseous.
Acrylate Recycling
[0150] It will be appreciated by the skilled artisan that the
polymerization mode of PPL from BPL proceeds in a manner contrary
to the typical polyester polymerization. While polyesters are
generally formed by the attack of a hydroxyl group at the carbonyl
of a carboxylic group, the strain of the BPL ring affords a unique
reactivity wherein a carboxylate anion attacks at the beta carbon,
resulting in a terminal carboxylate which may then react with
another unit of BPL to propagate the polymer chain:
##STR00029##
[0151] In some embodiments of provided methods, the polymerization
of BPL to PPL is catalyzed by an acrylate. Resulting polymer chains
will then comprise acrylate end groups. In some embodiments, a
carboxylate required to initiate polymerization is acrylic acid
provided via a return loop from a product stream. In some
embodiments, a portion of acrylic acid produced by a provided
method is returned to a reaction zone to initiate polymerization.
In some embodiments, acrylic acid formed in situ in a provided
method is sufficient to initiate and maintain the conversion of BPL
to PPL.
Heat Capturing
[0152] In some embodiments of provided methods, heat generated from
one portion of a process is captured. For example, polymerization
of BPL to PPL is an exothermic process and excess heat generated
from the reaction may be captured. In certain embodiments, captured
heat is low grade heat. In some embodiments of provided methods,
heat generated from a first reaction zone is captured and directed
to other processes. In certain embodiments, heat is directed to a
second reaction zone. In certain embodiments, heat is directed to
an upstream carbonylation process used to provide BPL. In some
embodiments, heat is directed to keep a product stream (e.g.,
acrylic acid vapor) at an appropriate temperature.
Reaction Mode
[0153] The methods herein place no particular limits on the type,
size or geometry of the reactor employed and indeed, in some cases,
more than one reactor may be employed. It is to be understood that
the term "reactor" as recited in the methods herein may actually
represent more than one physical reactor (for example the reactor
could be a train of continuous stirred tank reactors (CSTRs)
connected in parallel or in series, or a plurality of plug flow
reactors). In some embodiments, the "reactor" referred to in the
methods herein may also comprise more than one type of reactor (for
example the reactor could comprise a series of extruder reactors).
Many such combinations are known in the art and could be employed
by the skilled artisan to achieve an efficient reaction in the
methods described herein.
Solvents
[0154] As used herein, the term "high boiling solvent" refers to a
solvent having a boiling point higher than that of the pyrolysis
temperature of PPL. In some embodiments, a high boiling point
solvent has a boiling point higher than 150.degree. C. In some
embodiments, a high boiling point solvent has a boiling point
higher than 180.degree. C. In some embodiments, a high boiling
point solvent has a boiling point higher than 200.degree. C. In
some embodiments, a high boiling point solvent has a boiling point
higher than 220.degree. C. Boiling points used herein are the
boiling points at a pressure of 1 atm.
II. Systems
[0155] In another aspect, provided are systems for the synthesis of
acrylic acid. In some embodiments, a system for the conversion of
beta propiolactone to acrylic acid comprises:
[0156] (a) beta propiolactone (BPL); and
[0157] (b) a cationic solid catalyst comprising a carboxylate
salt,
[0158] wherein at or above the pyrolysis temperature of
poly(propiolactone) (PPL), BPL begins polymerizing to PPL in the
presence of the cationic solid catalyst, which PPL concurrently
thermally decomposes to acrylic acid;
[0159] wherein acrylic acid formed in situ maintains the reaction
polymerizing BPL to PPL.
[0160] In some variations, provided is a system for converting beta
propiolactone to acrylic acid, comprising:
[0161] a beta propiolactone (BPL) source;
[0162] a catalyst source; and
[0163] a reactor comprising: [0164] at least one inlet to receive
BPL from the BPL source and a polymerization catalyst from the
catalyst source, wherein the polymerization catalyst comprises a
carboxylate salt, and [0165] an outlet to output an acrylic acid
stream,
[0166] wherein the reactor is configured to (i) polymerize the BPL
to produce poly(propiolactone) (PPL) in the presence of the
polymerization catalyst, at or above the pyrolysis temperature of
PPL, and (ii) concurrently thermally decompose the PPL to produce
acrylic acid in situ, and wherein the acrylic acid produced in situ
maintains the polymerization of BPL to PPL.
[0167] In some embodiments, the polymerization catalyst is a
cationic solid catalyst comprising a carboxylate salt.
[0168] As mentioned above, in some embodiments provided methods
comprise a return loop of acrylic acid product to a reactor. Thus,
in some embodiments, a system for the conversion of beta
propiolactone to acrylic acid comprises:
[0169] (a) a reaction zone comprising beta propiolactone (BPL) and
a polymerization catalyst comprising a carboxylate salt;
[0170] wherein at or above the pyrolysis temperature of
poly(propiolactone) (PPL), BPL begins polymerizing to PPL, which
PPL concurrently thermally decomposes to acrylic acid; and
[0171] (b) a return loop for providing acrylic acid to the reaction
zone.
[0172] In some variations, provided is a system for converting beta
propiolactone to acrylic acid, comprising:
[0173] a reaction zone comprising beta propiolactone (BPL) and a
cationic solid catalyst comprising a carboxylate salt, wherein the
reaction zone is configured to (i) polymerize BPL to
poly(propiolactone) (PPL) in the presence of the cationic solid
catalyst, at or above the pyrolysis temperature of PPL, and (ii)
concurrently thermally decomposes the PPL to acrylic acid; and
[0174] a return loop for providing acrylic acid to the reaction
zone.
[0175] It should be understood that any of the cationic solid
catalysts described herein may be used in the systems of the
foregoing embodiments and variations.
Enumerated Embodiments
[0176] The following enumerated embodiments are representative of
some aspects of the invention.
1. A method for the synthesis of acrylic acid comprising the steps
of: [0177] (a) providing a feedstock stream comprising beta
propiolactone; [0178] (b) directing the feedstock stream to a
reaction zone where it is contacted with a suitable carboxylate
catalyst and where at least a portion of the beta propiolactone is
converted to poly(propiolactone); [0179] (c) maintaining the
reaction zone at a temperature at or above the pyrolysis
temperature of poly(propiolactone) such that the thermal
decomposition of poly(propiolactone) produces acrylic acid; and
[0180] (d) withdrawing an acrylic acid product stream from the
reaction zone; [0181] wherein steps (b) and (c) occur in the same
reaction zone. 2. The method of embodiment 1, further comprising
directing a return loop of a portion of the acrylic acid product
stream to the reaction zone. 3. A method for the synthesis of
acrylic acid comprising the steps of: [0182] (a) providing a
feedstock stream comprising beta propiolactone; [0183] (b)
directing the feedstock stream to a first reaction zone where it is
contacted with a suitable carboxylate catalyst and where at least a
portion of the beta propiolactone is converted to a
poly(propiolactone) product stream, wherein the first reaction zone
is maintained, at a temperature suitable for the formation of
poly(propiolactone); [0184] (c) directing the poly(propiolactone)
product stream to a second reaction zone, wherein the second
reaction zone is maintained at a temperature at or above the
pyrolysis temperature of poly(propiolactone) such that the thermal
decomposition of poly(propiolactone) produces acrylic acid: and
[0185] (d) withdrawing an acrylic acid product stream from the
second reaction zone. 4. The method of embodiment 2, wherein he
first reaction zone and second reaction zone are comprised within
an extruder reactor. 5. The method of embodiment 4, wherein the
extruder reactor provides a temperature gradient between the first
reaction zone and second reaction zone. 6. The method of embodiment
5, wherein the terminal temperature of the extruder is at or above
the pyrolysis temperature of poly(propiolactone). 7. The method of
any one of embodiments 3-6, further comprising the step of
capturing heat generated from the first reaction zone and directing
the heat to other processes. 8. The method of embodiment 7, wherein
the heat is directed to the second reaction zone. 9. The method of
any one of the preceding embodiments wherein the suitable
carboxylate catalyst is a salt of a compound of formula:
##STR00030##
[0185] wherein p is 0 to 9. 10. The method of any one of
embodiments 1-8, wherein the suitable carboxylate catalyst a salt
of a compound of formula:
##STR00031##
where p is from 0 to 9 and R.sup.a is a non-volatile moiety. 11.
The method of any one of the preceding embodiments, wherein the
suitable carboxylate catalyst is heterogeneous. 12. The method of
any one of the preceding embodiments, wherein after removal of all
acrylic acid product stream, the suitable carboxylate catalyst
remains in the reaction zone as a salt or melt. 13. The method of
embodiment 12, wherein the salt or melt is then recycled to the
reaction zone. 14. The method of any one of the preceding
embodiments, wherein the feedstock stream contains or is combined
with a high boiling solvent. 15. The method of embodiment 14,
further comprising the step of withdrawing a recycling stream of
the suitable carboxylate catalyst to the reaction zone. 16. The
method of any one of the preceding embodiments, further comprising
directing a return loop of a portion of the acrylic acid product
stream to the reaction zone. 17. The method of any one of the
preceding embodiments, wherein the beta propiolactone feedstock
stream is neat. 18. A system for the conversion of beta
propiolactone to acrylic acid comprising:
[0186] (a) beta propiolactone; and
[0187] (b) a cationic solid catalyst comprising a carboxylate
salt;
[0188] wherein at or above the pyrolysis temperature of
poly(propiolactone), beta propiolactone begins polymerizing to
poly(propiolactone) in the presence of the cationic solid catalyst,
which poly(propiolactone) concurrently thermally decomposes to
acrylic acid; and
[0189] wherein acrylic acid formed in situ maintains the reaction
polymerizing beta propiolactone to poly(propiolactone).
19. A system for the conversion of beta propiolactone to acrylic
acid comprising:
[0190] (a) a reaction zone comprising beta propiolactone (BPL) and
a cationic solid catalyst comprising a carboxylate salt;
[0191] wherein at or above the pyrolysis temperature of
poly(propiolactone) (PPL), BPL begins polymerizing to PPL, which
PPL concurrently thermally decomposes to acrylic acid; and
[0192] (b) a return loop for providing acrylic acid to the reaction
zone.
20. A method for producing acrylic acid, comprising:
[0193] (a) providing a feedstock stream comprising beta
propiolactone;
[0194] (b) directing the feedstock stream to a reaction zone;
[0195] (c) contacting the feedstock stream with a polymerization
catalyst in the reaction zone;
[0196] (d) polymerizing at least a portion of the beta
propiolactone to poly(propiolactone) in the reaction zone, wherein
the temperature of the reaction zone is at or above the pyrolysis
temperature of poly(propiolactone);
[0197] (e) thermally decomposing the poly(propiolactone) in the
reaction zone to produce acrylic acid; and
[0198] (f) withdrawing an acrylic acid product stream comprising
acrylic acid from the reaction zone;
[0199] wherein steps (b) and (e) occur in the same reaction
zone.
21. The method of embodiment 20, further comprising directing a
return loop comprising a portion of the acrylic acid product stream
to the reaction zone. 22. The method of embodiment 21, wherein the
return loop of acrylic acid is combined with the feedstock stream.
23. A method for producing acrylic acid, comprising:
[0200] (a) providing a feedstock stream comprising beta
propiolactone;
[0201] (b) directing the feedstock stream to a first reaction
one;
[0202] (c) contacting the feedstock stream with a polymerization
catalyst;
[0203] (d) polymerizing at least a portion of the beta
propiolactone to a poly(propiolactone) product stream, wherein the
first reaction zone is maintained at a temperature to promote
formation of poly(propiolactone);
[0204] (e) directing the poly(propiolactone) product stream to a
second reaction zone, wherein the second reaction zone is
maintained at a temperature at or above the pyrolysis temperature
of poly(propiolactone) such that the thermal decomposition of
poly(propiolactone) produces acrylic acid; and
[0205] (f) withdrawing an acrylic acid product stream from the
second reaction zone.
24. The method of embodiment 23, wherein the first reaction zone
and second reaction zone are in an extruder reactor. 25. The method
of embodiment 24, wherein the extruder reactor provides a
temperature gradient between the first reaction zone and second
reaction zone. 26. The method of embodiment 24 or 25, wherein the
extruder reactor has a terminal temperature at or above the
pyrolysis temperature of poly(propiolactone). 27. The method of any
one of embodiments 23 to 26, further comprising capturing heat
generated from the first reaction zone, and directing the heat to
other processes. 28. The method of embodiment 27, wherein the heat
is directed to the second reaction zone. 29. The method of any one
of embodiments 20 to 28, wherein the polymerization catalyst is a
salt of a compound of formula:
##STR00032##
wherein p is 0 to 9. 30. The method of any one of embodiments 20 to
28, wherein the polymerization catalyst is a salt of a compound of
formula:
##STR00033##
where p is from 0 to 9 and R.sup.a is a non-volatile moiety. 31.
The method of any one of embodiments 20 to 30, wherein the
polymerization catalyst is heterogeneous. 32. The method of any one
of embodiments 20 to 31, wherein after removal of all acrylic acid
product stream, the polymerization catalyst remains as a salt or
melt. 33. The method of embodiment 32, further comprising recycling
the salt or melt to the reaction zone. 34. The method of any one of
embodiments 20 to 33, wherein the feedstock stream contains or is
combined with a high boiling solvent. 35. The method of embodiment
34, further comprising withdrawing a recycling stream of the
polymerization catalyst from the reaction zone. 36. The method of
any one of embodiments 20 to 35, further comprising directing a
return loop of a portion of the acrylic acid product stream to the
reaction zone. 37. The method of any one of embodiments 20 to 36,
wherein the feedstock stream is neat. 38. A system for converting
beta propiolactone to acrylic acid, comprising:
[0206] (a) beta propiolactone; and
[0207] (b) a cationic solid catalyst comprising a carboxylate
salt,
[0208] wherein at or above the pyrolysis temperature of
poly(propiolactone), beta propiolactone begins polymerizing to
poly(propiolactone) in the presence of the cationic solid catalyst,
which poly(propiolactone) concurrently thermally decomposes to
acrylic acid, and
[0209] wherein acrylic acid formed in situ maintains the reaction
polymerizing beta propiolactone to poly(propiolactone).
39. A system for converting beta propiolactone to acrylic acid,
comprising:
[0210] (a) a reaction zone comprising beta propiolactone (BPL) and
a cationic solid catalyst comprising a carboxylate salt,
[0211] wherein at or above the pyrolysis temperature of
poly(propiolactone) (PPL), BPL begins polymerizing to PPL, which
PPL concurrently thermally decomposes to acrylic acid; and
[0212] (b) a return loop for providing acrylic acid to the reaction
zone.
40. The system of embodiment 38 or 39, wherein the carboxylate salt
is:
[0213] a salt of a compound of formula:
##STR00034##
wherein p is 0 to 9: or
[0214] a salt of a compound of formula:
##STR00035##
where p is front 0 to 9 and R.sup.a is a non-volatile moiety.
* * * * *