U.S. patent application number 14/291073 was filed with the patent office on 2014-10-16 for process for the production of gasoline blending components and aromatic hydrocarbons from lower alkanes.
This patent application is currently assigned to SHELL OIL COMPANY. The applicant listed for this patent is SHELL OIL COMPANY. Invention is credited to Yajnanarayana Halmuthur JOIS, Ann Marie LAURITZEN, Ajay Madhav MADGAVKAR.
Application Number | 20140309469 14/291073 |
Document ID | / |
Family ID | 44761419 |
Filed Date | 2014-10-16 |
United States Patent
Application |
20140309469 |
Kind Code |
A1 |
JOIS; Yajnanarayana Halmuthur ;
et al. |
October 16, 2014 |
PROCESS FOR THE PRODUCTION OF GASOLINE BLENDING COMPONENTS AND
AROMATIC HYDROCARBONS FROM LOWER ALKANES
Abstract
An integrated process for producing gasoline blending components
and aromatic hydrocarbons which comprises: (a) contacting a lower
alkane feed with an aromatic hydrocarbon conversion catalyst to
produce an aromatic reaction product mixture which is comprised of
benzene and/or toluene and/or xylene, C.sub.9 aromatic products,
C.sub.10 aromatic products including naphthalene and, optionally,
C.sub.11+ aromatic products, (b) separating and recovering the
aromatic reaction product mixture, (c) separating and recovering
benzene, (d) optionally separating recovering toluene and/or
xylene, and (e) separating and recovering the C.sub.9 aromatic
products and the C.sub.10 aromatic products which boil at a lower
temperature than naphthalene from the naphthalene and the C.sub.10
aromatic reaction products which boil at a higher temperature than
naphthalene and any C.sub.11+ aromatic products.
Inventors: |
JOIS; Yajnanarayana Halmuthur;
(Katy, TX) ; LAURITZEN; Ann Marie; (Houston,
TX) ; MADGAVKAR; Ajay Madhav; (Katy, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SHELL OIL COMPANY |
Houston |
TX |
US |
|
|
Assignee: |
SHELL OIL COMPANY
Houston
TX
|
Family ID: |
44761419 |
Appl. No.: |
14/291073 |
Filed: |
May 30, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13082756 |
Apr 8, 2011 |
8779224 |
|
|
14291073 |
|
|
|
|
61323017 |
Apr 12, 2010 |
|
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Current U.S.
Class: |
585/417 |
Current CPC
Class: |
C10L 10/10 20130101;
Y02P 20/125 20151101; C10G 2300/305 20130101; C10G 50/00 20130101;
C07C 2/76 20130101; C10G 2400/30 20130101; Y02P 20/10 20151101;
C07C 4/14 20130101; C10G 2300/1025 20130101; C10G 2400/02 20130101;
C10G 2300/1081 20130101; C07C 2/76 20130101; C07C 15/02 20130101;
C07C 4/14 20130101; C07C 15/04 20130101 |
Class at
Publication: |
585/417 |
International
Class: |
C10L 10/10 20060101
C10L010/10 |
Claims
1. An integrated process for producing gasoline blending components
and aromatic hydrocarbons which comprises: (a) contacting a lower
alkane feed with an aromatic hydrocarbon conversion catalyst to
produce an aromatic reaction product mixture which is comprised of
benzene and/or toluene and/or xylene, C9 aromatic products, C10
aromatic products including naphthalene and, optionally, C11+
aromatic products, (b) separating and recovering the aromatic
reaction product mixture, (c) separating and recovering benzene,
and (d) separating and recovering toluene and/or xylene and the C9
aromatic products and the C10 aromatic products which boil at a
lower temperature than naphthalene from the naphthalene and the C10
aromatic reaction products which boil at a higher temperature than
naphthalene and any C11+ aromatic products.
2. A process as claimed in claim 1 wherein step (d) further
comprises separating and recovering toluene and/or xylene and
separating and recovering the C9 aromatic products and the C10
aromatic products which boil at a lower temperature than
naphthalene.
3. A process as claimed in claim 1 further comprising
hydrodealkylating the toluene and/or xylene to produce additional
benzene.
4. A process as claimed in claim 1 wherein the C9 aromatic products
and the C10 aromatic products which boil at a lower temperature
than naphthalene comprises indane, methyl indane, indene, methyl
indene or mixtures thereof.
Description
[0001] This is a divisional application of U.S. patent application
Ser. No. 13/082,756, filed Apr. 8, 2011, which claims priority to
U.S. Provisional Application No. 61/323,017, filed on Apr. 12,
2010, which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a process for producing
gasoline blending components and aromatic hydrocarbons from lower
alkanes. The invention also relates to a novel gasoline blending
component.
BACKGROUND OF THE INVENTION
[0003] There is a projected global shortage for benzene which is
generally obtained, along with other aromatic hydrocarbons, by
separating a feedstock fraction which is rich in aromatic
compounds, such as reformate produced through a catalytic reforming
process and pyrolysis gasolines produced through a naphtha cracking
process, from non-aromatic hydrocarbons using a solvent extraction
process. To meet this projected supply shortage, numerous catalysts
and processes for on-purpose production of aromatics (including
benzene) from alkanes containing six or less carbon atoms per
molecule have been investigated. For example, U.S. Pat. No.
4,350,835 describes a process for converting ethane-containing
gaseous feeds to aromatics using a crystalline zeolite catalyst of
the ZSM-5-type family containing a minor amount of Ga. As another
example, U.S. Pat. No. 7,186,871 describes aromatization of
C.sub.1-C.sub.4 alkanes using a catalyst containing Pt and
ZSM-5.
[0004] It is well known to add certain blending components to
gasolines to improve the properties thereof such as the RON or the
MON. Commonly used blending components include naphthas (e.g.,
straight-run gasoline, alkylate, reformate, toluene, xylene),
cracked gasoline, pyrolysis gasoline, and paraffinic
hydrocarbons.
[0005] U.S. Pat. No. 6,353,143 describes fuel compositions which
are comprised of a branched hydrocarbon, such as an isoparaffin,
and an aromatic hydrocarbon. An example of a suitable aromatic
hydrocarbon given is AROMATIC 150 Fluid from Exxon Chemical which
typically is composed of a narrow-cut aromatic solvent containing
about 23 wt. % tetra-methyl benzenes, about 22 wt. % ethyl dimethyl
benzenes, about 15 wt. % mono-, di- and tri-methyl indanes, about 8
wt. % diethyl benzenes, about 8 wt. % naphthalene, about 5 wt. %
trimethyl benzenes, about 2 wt. % indane, and about 1 wt. % or less
of methyl ethyl benzenes, propyl benzenes, methyl propyl benzenes,
butyl benzenes, hexyl benzenes, indene, methyl naphthalenes, and
xylenes. Another example of an aromatic hydrocarbon given is
AROMMATIC 100 which typically is composed of a narrow-cut aromatic
solvent containing about 40 wt. % trimethyl benzenes, about 35 wt.
% methyl ethyl benzenes, about 1 wt. % propyl and isopropyl
benzenes, about 3 wt. % ethyl dimethyl benzenes, about 2 wt. %
methyl (n- and iso-) propyl benzenes, about 2 wt. % diethyl
benzenes, less than about 1 wt. % each of mono butyl benzenes and
tetramethyl benzenes, about 6 wt. % xylenes, and minor amounts of
ethyl benzene and C.sub.10-C.sub.11 saturates.
SUMMARY OF THE INVENTION
[0006] The present invention provides an integrated process for
producing gasoline blending components and aromatic hydrocarbons
which comprises: [0007] (a) contacting a lower alkane feed with an
aromatic hydrocarbon conversion catalyst to produce an aromatic
reaction product mixture which is comprised of benzene and/or
toluene and/or xylene, C.sub.9 aromatic products, C.sub.10 aromatic
products including naphthalene and, optionally, C.sub.11+ aromatic
products, [0008] (b) separating and recovering the aromatic
reaction product mixture, [0009] (c) separating and recovering
benzene, and [0010] (d) separating and recovering toluene and/or
xylene and the C.sub.9 aromatic products and the C.sub.10 aromatic
products which boil at a lower temperature than naphthalene from
the naphthalene and the C.sub.10 aromatic reaction products which
boil at a higher temperature than naphthalene and any C.sub.11+
aromatic products.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a flow diagram of a two stage aromatization
process wherein benzene, toluene and/or xylene and the C.sub.9-10
fraction are recovered separately.
[0012] FIG. 2 is a flow diagram of a two stage aromatization
process wherein the process also comprises hydrodealkylation of the
toluene and xylene to make additional benzene.
[0013] FIG. 3 is a flow diagram of the two stage aromatization
process wherein the C.sub.9-10 fraction is recovered together with
the toluene and xylene as a single gasoline blending component.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Gasolines typically comprise mixtures of hydrocarbons
boiling in the range from 25 to 230 .degree. C. (EN-ISO 3405), the
optimal ranges and distillation curves typically varying according
to climate and season of the year. The hydrocarbons in a gasoline
may be derived by any means known in the art, conveniently the
hydrocarbons may be derived in any known manner from straight-run
gasoline, synthetically-produced aromatic hydrocarbon mixtures,
thermally or catalytically cracked hydrocarbons, hydro-cracked
petroleum fractions, catalytically reformed hydrocarbons or
mixtures of these.
[0015] The specific distillation curve, hydrocarbon composition,
research octane number (RON) and motor octane number (MON) of the
gasoline are not critical. Conveniently, the research octane number
(RON) of the gasoline may be at least 80, for instance in the range
of from 80 to 110 (EN 25164). The motor octane number (MON) of the
gasoline may conveniently be at least 70, for instance in the range
of from 70 to 110 (EN 25163).
[0016] Gasoline is composed of many different hydrocarbons.
Typically, gasoline comprises components selected from one or more
of the following groups; saturated hydrocarbons, olefinic
hydrocarbons, aromatic hydrocarbons, and oxygenated hydrocarbons.
Typically, the aromatic hydrocarbon content of the gasoline may be
in the range of from 0 to 70 percent by volume based on the
gasoline (ASTM D1319).
[0017] Crude oil enters a refinery and is processed through various
units before being blended into gasoline. A refinery may have a
fluid catalytic cracker (FCC), an alkylate unit, and a reformer,
each of which produces gasoline blending components. Alkylate
gasoline, for example, is valuable because it has a very high
octane, and can be used to produce high-octane (and higher value)
blends. Light straight run gasoline is the least processed stream.
It is cheap to produce, but it has a low octane. The person
specifying the gasoline blends has to mix all of the components
together to meet the product specifications.
[0018] It is well known to add certain blending components to
gasoline to improve the properties thereof such as the RON or the
MON. Commonly used blending components include naphthas (e.g.,
straight-run gasoline, alkylate, reformate, benzene, toluene,
xylene), cracked gasoline, pyrolysis gasoline, and paraffinic
hydrocarbons. The present invention provides a novel gasoline
blending component which comprises from about 1 to 10 wt % indane,
from about 40 to 60% wt indene, from about 4 to 20 wt % C.sub.9
aromatics other than indane or indene, and from about 25 to 35 wt %
C.sub.10 aromatics other than naphthalene.
[0019] The process of the present invention comprises bringing into
contact a hydrocarbon feedstock containing lower alkanes, and
possibly other hydrocarbons, and a catalyst composition suitable
for promoting the reaction of such hydrocarbons to aromatic
hydrocarbons, such as benzene, at a temperature from about 400 to
about 700.degree. C. and a pressure from about 0.01 to about 1.0
Mpa absolute. The gas hourly space velocity (GHSV) per hour may
range from about 300 to about 6000. The process may be carried out
in a single stage or in multiple, preferably two, stages. If a
two-stage process is used, the conditions in each stage may fall in
the above ranges and may be the same or different.
[0020] Suitable feed streams for use herein include alkane streams
which may contain primarily one or more C.sub.2, C.sub.3, and/or
C.sub.4 alkanes (referred to herein as "lower alkanes"), for
example an ethane/propane/butane-rich stream derived from natural
gas, refinery or petrochemical streams including waste streams.
Examples of potentially suitable feed streams include (but are not
limited to) residual ethane and propane from natural gas (methane)
purification, pure ethane, propane and butane streams (also known
as Natural Gas Liquids) co-produced at a liquefied natural gas
site, C.sub.2-C.sub.5 streams from associated gases co-produced
with crude oil production, unreacted ethane "waste" streams from
steam crackers, and the C.sub.1-C.sub.3 byproduct stream from
naphtha reformers. The lower alkane feed may be deliberately
diluted with relatively inert gases such as nitrogen and/or with
various light hydrocarbons and/or with low levels of additives
needed to improve catalyst performance.
[0021] In one embodiment, the majority of the feedstock is
comprised of ethane and propane. In another embodiment, the
feedstock is comprised of mixed C.sub.2-C.sub.4 alkanes. In still
another embodiment, the feedstock is comprised of primarily propane
and butane. The feedstock may contain in addition other open chain
hydrocarbons containing between 3 and 8 carbon atoms as
coreactants. Specific examples of such additional coreactants are
propylene, isobutane, n-butenes and isobutene. The feed may contain
up to about 20 weight percent of C.sub.2-C.sub.4 olefins,
preferably no more than about 10 weight percent olefins. Too much
olefin content may cause an unacceptable amount of coking. The
hydrocarbon feedstock preferably may be comprised of at least about
30 percent by weight of C.sub.2-4 hydrocarbons, preferably at least
about 50 percent by weight.
[0022] In one embodiment, the lower alkane feed is comprised of at
least propane and ethane and the process is carried out in two
stages as described in copending, commonly assigned provisional
U.S. Patent Application No. 61/257,085, entitled Process for the
Conversion Mixed Lower Alkanes to Aromatic Hydrocarbons, filed Nov.
2, 2009, which is herein incorporated by reference in its entirety.
In the first stage, the reaction conditions may be optimized for
the conversion of propane to benzene. In the second stage, reaction
conditions may be optimized for the conversion of ethane to
benzene. Optionally, the second stage reaction conditions may also
be optimized for the conversion to BTX of any other non-aromatic
hydrocarbons which may be produced in the first stage.
[0023] In another embodiment, as described in copending, commonly
assigned provisional U.S. Patent Application No. 61/257,149,
entitled Process for the Conversion Lower Alkanes to Aromatic
Hydrocarbons, filed Nov. 2, 2009, which is herein incorporated by
reference in its entirety, the process (a) comprises alternately
contacting the lower alkane feed with an aromatization catalyst in
a reactor for a short period of time, preferably 10 minutes or
less, and then contacting the aromatization catalyst with hydrogen
at elevated temperature for a short period of time, preferably 20
minutes or less, (b) repeating the cycle of step (a) at least one
time, (c) regenerating the aromatization catalyst by contacting it
with an oxygen-containing gas at elevated temperature, and (d)
repeating steps (a) through (c) at least one time.
[0024] One important advantage of the aromatization process used
herein is that little or no C.sub.5+ non-aromatic hydrocarbons are
produced. The C.sub.1-4 non-aromatic hydrocarbons which are
produced may be recycled or used for fuel, etc. The major products
produced are aromatic. Benzene, and generally toluene and xylene,
are recovered, leaving a substantial amount of C.sub.9+ aromatic
hydrocarbons. We have discovered that a significant portion of the
C.sub.9+ fraction produced from lower alkanes in this aromatization
process may be used as a gasoline-blending component with
attractive properties. Accordingly, a product separation scheme is
incorporated in the aromatization process to efficiently separate
and recover the desirable portion of the C.sub.9+ mixture so that a
maximum amount of desirable gasoline blending component is
obtained. The C.sub.9+ fraction includes naphthalene and higher
boiling C.sub.10+ aromatic hydrocarbons which are not useful for
gasoline blending components because its boiling range is higher
than specified/typical gasoline range.
[0025] In the present invention, the C.sub.9 aromatic hydrocarbons
and the C.sub.10 aromatic hydrocarbons which boil at lower
temperatures than naphthalene are recovered separately. The C.sub.9
aromatic hydrocarbons include indane, indene, durene,
propylbenzene, etc. and the lower boiling C.sub.10 aromatic
hydrocarbons include methylindane, methylindene,
methylpropylbenzene, butylbenzene, diethylbenzene, etc. The
combined C.sub.9 aromatic hydrocarbons and C.sub.10 aromatic
hydrocarbons which boil at lower temperatures than naphthalene
comprise the gasoline blending component of the present invention.
It may comprise from about 1 to 10 wt % indane, from about 40 to 60
wt % indene, from about 4 to 20 wt % C.sub.9 aromatics other than
indane or indene, and from about 25 to 35 wt % C.sub.10 aromatics
other than naphthalene.
[0026] Indane is a hydrocarbon petrochemical compound with chemical
formula C.sub.9H.sub.10. Derivatives include compounds such as
1-methyl-indane and 2-methyl-indane (where one methyl group is
attached to the five carbon ring), 4-methyl-indane and
5-methyl-indane (where one methyl group is attached to the benzene
ring), various dimethyl-indanes, and various pharmaceutical
derivatives. Indene is an unsaturated polycyclic hydrocarbon with
chemical formula C.sub.9H.sub.8. It is composed of a benzene ring
fused with a cyclopentene ring.
[0027] Multiple chemical analyses of the C.sub.9+ fraction obtained
experimentally show that indane and indene form the majority of the
C.sub.9 molecules while methyl substituted indane and indene and
naphthalene form the majority of the C.sub.10 molecules. Indane and
indene
##STR00001##
are similar in structure to benzene, ethyl benzene and propyl
benzene which are known to have high octane and high flame speed
boosting properties as shown in Table 1.
TABLE-US-00001 TABLE 1 Flame Speed Compound RON MON cm/sec b.p.
.degree. C. Benzene 105 99 84 80.1 Toluene 120 109 67.9 110.6
Isooctane 100 100 67 98.5 Ethylbenzene 111.2 97.9 76.9 136.2 1,2,4
Trimethylbenzene 110.5 105.8 58.3 169.4 (Pseudocumene) 1,3,5
Trimethylbenzene (Mesitylene) 120.3 120.3 56 164.7 isopropylbenzene
113.1 99.3 76.3 152.4 n-propylbenzene 74.1 t-butylbenzene 75.7
[0028] FIG. 1 is a flow diagram of a two stage aromatization
process wherein a C.sub.9-10 only fraction is recovered. Lower
alkane feed enters stage 1 aromatization reactor 2 through line 1.
The reaction products are combined with the reaction products from
stage 2 aromatization reactor 3 in line 4 which is conveyed to a
vapor-liquid separator 5. The liquid bottoms leave the separator 5
in line 6 and are conveyed to the debenzenizer 7 wherein benzene is
separated from the other aromatic products and is recovered in line
8. The other aromatic products in the bottom stream 9 are conveyed
to the toluene-xylene-C.sub.9-10 separation stage 10. The toluene
and xylene leave separation stage 10 through line 11 and are
recovered separately as toluene in line 12 and xylene in line 13.
The C.sub.9-10 fraction is taken out of separation stage 10 and
recovered in line 14. The remaining C.sub.9-10+ aromatics leave
stage 10 through line 15.
[0029] Vapor stream 16 leaves separator 5 and is compressed in
compressor 17. Any aromatics carried over to the compressor are
conveyed to the debenzenizer 7 through line 18. The other liquids
are conveyed through line 19 to demethanizer 20 wherein the methane
and hydrogen are separated and recovered as fuel gas in line 21.
The bottom stream 22 of the demethanizer 20 contains C.sub.24
hydrocarbons which are recycled to the second stage aromatization
reactor 3.
[0030] FIG. 2 is a flow diagram of the two stage aromatization
process wherein the process scheme of FIG. 1 includes at the end a
hydrodealkylation section wherein the toluene and xylene are
reacted to produce more benzene. Most of the process description is
the same as for FIG. 1. Instead of being separated, the toluene and
xylene in line 11 are conveyed to a hydrodealkylation unit 26 which
produces additional benzene in line 28 and some fuel gas components
in line 29. Unreacted toluene and xylene are recycled to the
debenzenizer through line 27. The overhead stream 21 from
demethanizer 20 is conveyed to separator 23 which separates
hydrogen from other fuel gas components. The hydrogen is conveyed
through line 25 to the hydrodealkylation unit 26. The remaining
fuel gas components from separator 23 are combined with line 29 and
recovered as fuel gas through line 24.
[0031] FIG. 3 is a flow diagram of a two stage aromatization
process wherein the C.sub.9-10 fraction is recovered together with
the toluene and xylene as a single gasoline blending component. In
this embodiment, the toluene, xylene and the C.sub.9-10 fractions
are not recovered separately but are recovered together as a
combined gasoline blending component in line 11.
[0032] Any one of a variety of catalysts may be used to promote the
reaction of the lower alkanes to aromatic hydrocarbons. One such
catalyst is described in U.S. Pat. No. 4,899,006 which is herein
incorporated by reference in its entirety. The catalyst composition
described therein comprises an aluminosilicate having gallium
deposited thereon and/or an aluminosilicate in which cations have
been exchanged with gallium ions. The molar ratio of silica to
alumina is at least 5:1.
[0033] Another catalyst which may be used in the process of the
present invention is described in EP 0 244 162. This catalyst
comprises the catalyst described in the preceding paragraph and a
Group VIII metal selected from rhodium and platinum. The
aluminosilicates are said to preferably be MFI or MEL type
structures and may be ZSM-5, ZSM-8, ZSM-11, ZSM-12 or ZSM-35.
[0034] Other catalysts which may be used in the process of the
present invention are described in U.S. Pat. No. 7,186,871 and U.S.
Pat. No. 7,186,872, both of which are herein incorporated by
reference in their entirety. The first of these patents describes a
platinum containing ZSM-5 crystalline zeolite synthesized by
preparing the zeolite containing the aluminum and silicon in the
framework, depositing platinum on the zeolite and calcining the
zeolite. The second patent describes such a catalyst which contains
gallium in the framework and is essentially aluminum-free.
[0035] Additional catalysts which may be used in the process of the
present invention include those described in U.S. Pat. No.
5,227,557, hereby incorporated by reference in its entirety.
[0036] These catalysts contain an MFI zeolite plus at least one
noble metal from the platinum family and at least one additional
metal chosen from the group consisting of tin, germanium, lead, and
indium.
[0037] One preferred catalyst for use in this invention is
described in U.S. Patent Application Publication No. 2009/0209795.
This publication is hereby incorporated by reference in its
entirety. This publication describes a catalyst comprising: (1)
0.005 to 0.1% wt (% by weight) platinum, based on the metal,
preferably 0.01 to 0.05% wt, (2) an amount of an attenuating metal
selected from the group consisting of tin, lead, and germanium,
which is no more than 0.02% wt less than the amount of platinum,
preferably not more than 0.2% wt of the catalyst, based on the
metal; (3) 10 to 99.9% wt of an aluminosilicate, preferably a
zeolite, based on the aluminosilicate, preferably 30 to 99.9% wt,
preferably selected from the group consisting of ZSM-5, ZSM-11,
ZSM-12, ZSM-23, or ZSM-35, preferably converted to the H+ form,
preferably having a SiO.sub.2/Al.sub.2O.sub.3 molar ratio of from
20:1 to 80:1, and (4) a binder, preferably selected from silica,
alumina and mixtures thereof.
[0038] Another preferred catalyst for use in this invention is
described in PCT Publication No. WO 2009/105447. This publication
is hereby incorporated by reference in its entirety. The
publication describes a catalyst comprising: (1) 0.005 to 0.1% wt
(% by weight) platinum, based on the metal, preferably 0.01 to
0.06% wt, most preferably 0.01 to 0.05% wt, (2) an amount of iron
which is equal to or greater than the amount of the platinum but
not more than 0.50% wt of the catalyst, preferably not more than
0.20% wt of the catalyst, most preferably not more than 0.10% wt of
the catalyst, based on the metal; (3) 10 to 99.9% wt of an
aluminosilicate, preferably a zeolite, based on the
aluminosilicate, preferably 30 to 99.9% wt, preferably selected
from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-23, or
ZSM-35, preferably converted to the H+form, preferably having a
SiO.sub.2/Al.sub.2O.sub.3 molar ratio of from 20:1 to 80:1, and (4)
a binder, preferably selected from silica, alumina and mixtures
thereof.
[0039] Another preferred catalyst for use in this invention is
described in U.S. Patent Application Publication No. 2009/0209794.
This publication is hereby incorporated by reference in its
entirety. This publication describes a catalyst comprising: (1)
0.005 to 0.1 wt % (% by weight) platinum, based on the metal,
preferably 0.01 to 0.05% wt, most preferably 0.02 to 0.05% wt, (2)
an amount of gallium which is equal to or greater than the amount
of the platinum, preferably no more than 1 wt %, most preferably no
more than 0.5 wt %, based on the metal; (3) 10 to 99.9 wt % of an
aluminosilicate, preferably a zeolite, based on the
aluminosilicate, preferably 30 to 99.9 wt %, preferably selected
from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-23, or
ZSM-35, preferably converted to the H+form, preferably having a
SiO.sub.2/Al.sub.2O.sub.3 molar ratio of from 20:1 to 80:1, and (4)
a binder, preferably selected from silica, alumina and mixtures
thereof.
[0040] The unreacted methane and byproduct hydrocarbons may be used
in other steps, stored and/or recycled. It may be necessary to cool
these byproducts to liquefy them. When the ethane or mixed lower
alkanes originate from an LNG plant as a result of the purification
of the natural gas, at least some of these byproducts may be cooled
and liquefied using the heat exchangers used to liquefy the
purified natural gas (methane).
[0041] The toluene and xylene may be converted into benzene by
hydrodealkylation. The hydrodealkylation reaction involves the
reaction of toluene, xylenes, ethylbenzene, and higher aromatics
with hydrogen to strip alkyl groups from the aromatic ring to
produce additional benzene and light ends including methane and
ethane which are separated from the benzene. This step
substantially increases the overall yield of benzene and thus is
highly advantageous.
[0042] Both thermal and catalytic hydrodealkylation processes are
known in the art. Methods for hydrodealkylation are described in
U.S. Patent Application Publication No. 2009/0156870 which is
herein incorporated by reference in its entirety.
[0043] The integrated process of this invention may also include
the reaction of benzene with propylene to produce cumene which may
in turn be converted into phenol and/or acetone. The propylene may
be produced separately in a propane dehydrogenation unit or may
come from olefin cracker process vent streams or other sources.
Methods for the reaction of benzene with propylene to produce
cumene are described in U.S. Patent Application Publication No.
2009/0156870 which is herein incorporated by reference in its
entirety.
[0044] The integrated process of this invention may also include
the reaction of benzene with olefins such as ethylene. The ethylene
may be produced separately in an ethane dehydrogenation unit or may
come from olefin cracker process vent streams or other sources.
Ethylbenzene is an organic chemical compound which is an aromatic
hydrocarbon. Its major use is in the petrochemical industry as an
intermediate compound for the production of styrene, which in turn
is used for making polystyrene, a commonly used plastic material.
Methods for the reaction of benzene with ethylene to produce
ethylbenzene are described in U.S. Patent Application Publication
No. 2009/0156870 which is herein incorporated by reference in its
entirety.
[0045] Styrene may then be produced by dehydrogenating the
ethylbenzene. One process for producing styrene is described in
U.S. Pat. No. 4,857,498 which is herein incorporated by reference
in its entirety. Another process for producing styrene is described
in U.S. Pat. No. 7,276,636 which is herein incorporated by
reference in its entirety.
EXAMPLES
[0046] The following examples are provided for illustrative
purposes only and are not intended to limit the scope of the
invention.
Example 1
[0047] Indane and indene were obtained from vendors. Toluene was
used as a benchmark in this study of the fuel blending properties.
The RON and MON of neat indane, indene, toluene, and a base fuel
were tested using ASTM D-2699 and ASTM D-2700 test method. All
compounds were tested in triplicate and the average of those
results were presented in Table 2. The RON and MON of the base fuel
and toluene were reasonably high as expected and the RON and MON of
indane and indene were also reasonable high.
TABLE-US-00002 TABLE 2 Neat Density Average delta g/ml RON MON R +
M/2 R - M 0.743 Base Fuel 85.4 79.0 82.1 6.5 0.865 Toluene 114.5
106.0 110.3 8.5 0.965 Indane 100.7 85.5 93.1 15.2 0.996 Indene
108.0 98.5 103.2 9.5
[0048] The RON and MON of 1.2 v % indane and indene in base fuel
blends were measured (see the top part of Table 3). The RON and MON
of 3.7 v % toluene, 4.7 v % indane and 4.6 v % indene in base fuel
blends were also measured (see the bottom part of Table 3). Table 3
below shows an increase in Research Octane Number of 0.43 and 0.5
with 1.2v % of indane and indene, respectively. Table 3 shows an
increase in Research Octane Number of 0.90 and 0.80 with 4.7 v % of
indane and 4.6 v % indene, respectively.
TABLE-US-00003 TABLE 3 Average delta Density R + R + (g/ml) RON MON
M/2 RON MON M/2 0.743 Base Fuel (BF) 86.3 79.8 83.0 0.965 Indane
86.7 79.8 83.2 0.43 -0.03 0.2 (1.2 v % in BF) 0.996 Indene (1.2 v
%) 86.8 79.5 83.1 0.50 -0.30 0.1 0.743 Base Fuel 86.67 79.83 83.3
0.865 Toluene (3.7 v %) 87.6 80.23 83.9 0.93 0.40 0.7 0.965 Indane
(4.7 v %) 87.57 80.23 83.9 0.90 0.40 0.6 0.996 Indene (4.6 v %)
87.47 79.57 83.5 0.80 -0.27 0.2
[0049] Such increase in octane number is known in the literature
for aromatic molecules. However, it is generally compensated for by
a decrease in flame speed. The flame speeds of above molecules were
measured using the Leeds University bomb experiment technique at
Leeds University facility. Fuel samples were tested under laminar
conditions with initial conditions of 5 bar absolute pressure and
360K. All the burning velocities (flame speed) were measured at
stoichiometric ratio of fuel to air. The experiments were conducted
using the Leeds Mkt fan stirred combustion vessel (Refer to
www.engineering.leeds.ac.uk/mech for their facility). It is a
stainless sphere of 30 liter volume with extensive optical access.
The fuels were injected into the bomb and allowed to vaporize
fully, then a stoichometric amount of air was added. Content were
heated to the desired temperature, mixed by stirring. Mixing fans
were turned off prior to ignition. Pressure measured after 0.1
second of the ignition is recorded in Table 4. To determine if
there was any significant change due to the presence of a
component, it was decided to do experiments using 20 v % of the
components in commercial grade gasoline. No significant change in
flame speed was noted for indane or indene as shown in Table 4. The
data in Tables 1-4 indicate that indane, indene, other C.sub.9
aromatics, and certain C.sub.10 aromatics other than naphthalene
would comprise suitable gasoline blending components.
TABLE-US-00004 TABLE 4 Flame Speed Data Blend Composition Flame
Speed Molecule % in Gasoline P/bar at 0.1 Second Gasoline 100 17.35
Indane 20 17.24 Indene 20 16.10
Example 2
[0050] Four runs were carried out in a lab-scale aromatization
reactor at 0 kPag, 600.degree. C. reactor wall temperature with
repeated cycles of 10 minute exposure of the catalyst to feed
followed by 20 minute exposure of the catalyst to hot hydrogen
stripping. The feed and other conditions are described in Table 5
below. The catalysts used in these runs were prepared as described
in U.S. Patent Application Publication No. 2009/02009794, which is
incorporated by reference, with target metal loadings of 0.025 wt %
platinum and 0.09 wt % gallium or 0.09 wt % platinum and 0.25 wt %
gallium, on extrudates consisting of 80 wt % ZSM-5 CBV 2314 zeolite
(available from Zeolyst International) and 20 wt % alumina binder.
A gas chromatograph was used to provide quantitative analysis of
the total product stream.
[0051] As shown in Table 5, the total C.sub.9+ aromatics fraction
accounted for about 8-15 wt % of the total aromatics product in
runs conducted with all-ethane and mixed ethane/propane feeds. The
C.sub.9-10 aromatics fraction excluding naphthalene ranged between
about 45 and 60% w of the total C.sub.9+ aromatics product or about
4-8% w of the total aromatics product in these runs.
TABLE-US-00005 TABLE 5 Run No. 1 2 3 4 Feed Composition Ethane, %
wt 100 100 50 50 Propane, % wt -0- -0- 50 50 Feed Rate, GHSV 800
800 1000 1000 Total Hrs on Feed 14.4 50.7 27.2 50.7 Avg Total C2 +
C3 Conversion per 38.40 33.66 47.26 47.06 Pass, % Avg Total Arom.
Yield per Pass, 23.57 20.01 30.19 32.81 % wt Avg C9+ Arom. Yield
per Pass, 3.29 2.61 3.30 2.95 % wt Avg C9-C10 Arom. (Except
Naphthalane) Yield as % of C9+ Aromatics 45.3 59.8 56.7 48.5 Yield
as % of Total Aromatics 6.3 7.8 6.2 4.4 Avg Naphthalene and Higher
Aromatics Yield as % of C9+ Aromatics 54.7 40.2 43.3 51.5 Yield as
% of Total Aromatics 7.6 5.2 4.7 4.6 Final Boiling Point of
Collected NA 493 NA 453 Liquid Product, .degree. C.
* * * * *
References