U.S. patent application number 11/915088 was filed with the patent office on 2008-09-04 for method for making an epoxy starting from a chlorhydrine.
This patent application is currently assigned to SOLVAY (SOCIETE ANONYME). Invention is credited to Dominique Balthasart, Patrick Gilbeau, Philippe Krafft, Valentine Smets.
Application Number | 20080214848 11/915088 |
Document ID | / |
Family ID | 39543862 |
Filed Date | 2008-09-04 |
United States Patent
Application |
20080214848 |
Kind Code |
A1 |
Krafft; Philippe ; et
al. |
September 4, 2008 |
Method For Making an Epoxy Starting From a Chlorhydrine
Abstract
Process for preparing an epoxide, comprising at least one step
of purifying the epoxide formed, the epoxide being at least partly
prepared by a process of dehydrochlorinating a chlorohydrin, the
latter being at least partly prepared by a process of chlorinating
a polyhydroxylated aliphatic hydrocarbon, an ester of a
polyhydroxylated aliphatic hydrocarbon or a mixture thereof.
Inventors: |
Krafft; Philippe; (Rhode
Saint Genese, BE) ; Balthasart; Dominique; (Brussels,
BE) ; Smets; Valentine; (Brussels, BE) ;
Gilbeau; Patrick; (Braine-le-Comte, BE) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
SOLVAY (SOCIETE ANONYME)
Brussels
BE
|
Family ID: |
39543862 |
Appl. No.: |
11/915088 |
Filed: |
May 19, 2006 |
PCT Filed: |
May 19, 2006 |
PCT NO: |
PCT/EP2006/062466 |
371 Date: |
November 20, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60734635 |
Nov 8, 2005 |
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60734657 |
Nov 8, 2005 |
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60734636 |
Nov 8, 2005 |
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60734627 |
Nov 8, 2005 |
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60734634 |
Nov 8, 2005 |
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60734658 |
Nov 8, 2005 |
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60734637 |
Nov 8, 2005 |
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60734659 |
Nov 8, 2005 |
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Current U.S.
Class: |
549/540 |
Current CPC
Class: |
C07C 29/82 20130101;
B01D 3/143 20130101; C07C 29/62 20130101; C07D 303/08 20130101;
C07D 301/26 20130101; C07D 301/02 20130101; C07D 301/06 20130101;
C07C 29/62 20130101; C07C 31/36 20130101; C07C 29/82 20130101; C07C
31/36 20130101 |
Class at
Publication: |
549/540 |
International
Class: |
C07D 301/32 20060101
C07D301/32 |
Foreign Application Data
Date |
Code |
Application Number |
May 20, 2005 |
EP |
05104321.4 |
May 20, 2005 |
FR |
0505120 |
Claims
1-30. (canceled)
31. A process for preparing an epoxide, comprising at least one
step of purifying the epoxide formed, the epoxide being at least
partly prepared by a process of dehydrochlorinating a chlorohydrin,
the latter being at least partly prepared by a process of
chlorinating a polyhydroxylated aliphatic hydrocarbon, an ester of
a polyhydroxylated aliphatic hydrocarbon or a mixture thereof.
32. The process according to claim 31, wherein the step of
purifying the epoxide formed is preceded by at least one step of
chemically treating the epoxide and wherein the chemical treating
is washing with an aqueous solution of a metal salt.
33. The process according to claim 31, wherein the step of
purifying the epoxide comprises at least one distillation step.
34. The process according to claim 31, wherein at least one
fraction of the chlorohydrin is prepared by a process of
chlorinating an unsaturated alcohol.
35. The process according to claim 31, wherein at least one
fraction of the chlorohydrin is prepared by a process of
hypochlorinating an olefin.
36. The process according to claim 31, wherein at least one part of
the epoxide is prepared by a process of epoxidizing an olefin.
37. The process according to claim 31, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (a) at least one step of reacting the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof with the chlorinating agent,
optionally in the presence of an organic acid as catalyst, to give
a mixture containing the chlorohydrin and water, (b) at least one
step of stripping and/or distilling at least a first fraction of
the mixture obtained in step (a) so as to give a first mixture
concentrated with chlorohydrin and with water.
38. The process according to claim 37, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (I) at least one step of decantation of the first
concentrated mixture obtained in step (b) so as to give at least a
first aqueous phase concentrated with water and a first organic
phase concentrated with chlorohydrin.
39. The process according to claim 37, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (c) at least one additional step of stripping and/or
distilling a second fraction of the mixture obtained in step (a) so
as to give at least a second mixture concentrated with chlorohydrin
and with water.
40. The process according to claim 39, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (II) at least one step of decantation of the second
concentrated mixture obtained in step (c) so as to give at least a
second aqueous phase concentrated with water and a second organic
phase concentrated with chlorohydrin.
41. The process according to claim 37, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (d) at least one additional step of hydrolytically
treating a third fraction of the mixture obtained in step (a) so as
to regenerate the acidic catalyst.
42. The process according to claim 37, wherein the process of
chlorinating the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (e) at least one additional step of oxidative treatment
at a temperature greater than or equal to 800.degree. C. of a
fourth fraction of the mixture obtained in step (a) so as to give a
gaseous mixture containing the chlorinating agent.
43. The process according to claim 31, wherein halogenated ketones
are formed in the process for preparing the chlorohydrin and
comprising optionally (f) a step of treating the chlorohydrin so as
to reduce the halogenated ketone content of the chlorohydrin.
44. The process according to claim 31, wherein at least part of the
polyhydroxylated aliphatic hydrocarbon, of the ester of
polyhydroxylated aliphatic hydrocarbon or of the mixture thereof is
obtained starting from renewable raw materials.
45. The process according to claim 31, wherein at least part of the
polyhydroxylated aliphatic hydrocarbon, of the ester of
polyhydroxylated aliphatic hydrocarbon or of the mixture thereof is
obtained starting from fossil raw materials.
46. The process according to claim 35, wherein the olefin is
selected from ethylene, propylene, allyl chloride and mixtures of
at least two thereof.
47. The process according to claim 31, wherein the polyhydroxylated
aliphatic hydrocarbon is selected from ethylene glycol, propylene
glycol, chloropropanediol, glycerol and mixtures of at least two
thereof, and wherein the chlorohydrin is selected from
chloroethanol, chloropropanol, chloropropanediol, dichloropropanol
and mixtures of at least two thereof and wherein the epoxide is
selected from ethylene oxide, propylene oxide, glycidol,
epichlorohydrin and mixtures of at least two thereof.
48. The process according to claim 35, wherein the olefin is allyl
chloride, the chlorohydrin is dichloropropanol and the epoxide is
epichlorohydrin.
49. The process according to claim 31, wherein the chlorination of
the polyhydroxylated aliphatic hydrocarbon, of the ester of
polyhydroxylated aliphatic hydrocarbon or of the mixture thereof is
carried out with a chlorinating agent containing hydrogen chloride,
wherein at least a portion of the hydrogen chloride has come from a
process for preparing allyl chloride, from a process for preparing
chloromethanes, from a process of chlorinolysis and/or from a
process for oxidizing chlorine compounds at a temperature greater
than 800.degree. C., and wherein the hydrogen chloride is a
combination of gaseous hydrogen chloride and an aqueous solution of
hydrogen chloride, or an aqueous solution of hydrogen chloride.
50. The process according to claim 31, wherein the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof is subjected to a purification
treatment so as to reduce the water content, the amount of salts
and/or the amount of organic compounds other than the
polyhydroxylated aliphatic hydrocarbon, before the chlorination
process.
51. The process according to claim 31, comprising at least one
process for purifying aqueous and/or organic liquid effluents
and/or gaseous effluents and wherein the treatment of purifying the
aqueous liquid effluents comprises at least one chemical treatment
by chlorination or one biological treatment, and the treatment for
purifying the gaseous effluents comprises at least one treatment by
oxidation at a temperature greater than or equal to 800.degree. C.
in the presence of air.
52. The process according to claim 31, followed by preparation of
ethylene glycol, of di- and polyethylene glycols, of mono-, di- and
triethanolamines, of propylene 1,2-glycol, of dipropylene glycol,
of propylene glycol ethers, of isopropylamines, of glycerol, of
polyglycerols, of epoxy resins, of synthetic elastomers, of
glycidyl ethers and of polyamide resins.
Description
[0001] The present patent application claims the benefit of patent
application FR 05.05120 and of patent application EP 05104321.4,
both filed on 20 May 2005, and of provisional U.S. patent
applications 60/734,659, 60/734,627, 60/734,657, 60/734,658,
60/734,635, 60/734,634, 60/734,637 and 60/734,636, all filed on 8
Nov. 2005, the content of all of which is incorporated here by
reference.
[0002] The present invention relates to a process for preparing an
epoxide.
[0003] Epoxides are important raw materials for the production of
other compounds.
[0004] Ethylene oxide is used, for example, for the production of
ethylene glycol, of di- and polyethylene glycols, of mono-, di- and
triethanolamines, etc (see K. Weissermel and H.-J. Arpe in
Industrial Organic Chemistry, Third Completely Revised Edition,
VCH, 1997, page 149). Propylene oxide is an important intermediate
in the preparation of propylene 1,2-glycol, of dipropylene glycol,
of ethers of propylene glycol, of isopropylamines, etc (see K.
Weissermel and H.-J. Arpe in Industrial Organic Chemistry, Third
Completely Revised Edition, VCH, 1997, page 275). Epichlorohydrin
is an important raw material for the production of glycerol, of
epoxy resins, of synthetic elastomers, of glycidyl ethers, of
polyamide resins, etc (see Ullmann's Encyclopedia of Industrial
Chemistry, Fifth Edition, Vol. A9, p. 539).
[0005] In the industrial production of propylene oxide the most
commonly used technology comprises the following steps:
hypochlorination of propylene to monochloropropanol and
dehydrochlorination of the monochloropropanol to propylene oxide by
means of an aqueous alkaline solution.
[0006] In the industrial production of epichlorohydrin the most
commonly used technology comprises the following steps:
high-temperature free-radical substitutive chlorination of
propylene to allyl chloride, hypochlorination of the allyl chloride
thus synthesized to dichloropropanol, and dehydrochlorination of
the dichloropropanol to epichlorohydrin by means of an aqueous
alkaline solution. Another technology, used on a smaller scale,
comprises the following steps: catalytical acetoxylation of
propylene to allyl acetate, hydrolysis of the allyl acetate to
allyl alcohol, catalytic chlorination of the allyl alcohol to
dichloropropanol, and alkaline dehydrochlorination of the
dichloropropanol to epichlorohydrin. Other technologies, which have
not yet gained industrial application, may be considered, including
the direct catalytic oxidation of allyl chloride to epichlorohydrin
using hydrogen peroxide, or the hydrochlorination of glycerol to
dichloropropanol, followed by alkaline dehydrochlorination of the
dichloropropanol thus formed to epichlorohydrin.
[0007] Application WO 2005/054167 of SOLVAY SA describes a process
for preparing dichloropropanol by reacting glycerol with hydrogen
chloride in the presence of an organic acid as catalyst. In that
process the dichloropropanol is separated from the other reaction
products, the hydrogen chloride and the organic acid, and the
dichloropropanol is subjected to a dehydrochlorination reaction so
as to give reaction products containing epichlorohydrin. The
dehydrochlorination may be carried out in the presence of a basic
agent and, in particular, an aqueous solution of a basic agent. The
epichlorohydrin formed may be used in the preparation of
polyglycerols or epoxy resins. The presence of impurities such as,
for example, chlorinated ketones, or aldehydes, in the
epichlorohydrin obtained may, however, be detrimental for the
applications mentioned.
[0008] In accordance with the invention it has been found that the
presence of impurities in the epoxide may be, for example, the
cause of problems of coloration of the organic products obtained,
or the source of unwanted chemical contamination of these products,
by halogens, for example.
[0009] The objective of the present invention is to provide a
process for preparing an epoxide that does not exhibit these
drawbacks.
[0010] The invention accordingly provides a process for preparing
an epoxide, comprising at least one step of purifying the epoxide
formed, the epoxide being at least partly prepared by a process of
dehydrochlorinating a chlorohydrin, the latter being at least
partly prepared by a process of chlorinating a polyhydroxylated
aliphatic hydrocarbon, an ester of a polyhydroxylated aliphatic
hydrocarbon or a mixture thereof.
[0011] The term "epoxide" is used herein to describe a compound
containing at least one oxygen bridged on a carbon-carbon bond.
Generally speaking, the carbon atoms of the carbon-carbon bond are
adjacent and the compound may contain atoms other than carbon atoms
and oxygen atoms, such as hydrogen atoms and halogens. The
preferred epoxides are ethylene oxide, propylene oxide, glycidol,
epichlorohydrin and mixtures of at least two thereof.
[0012] The term "olefin" is used herein to describe a compound
containing at least one carbon-carbon double bond. Generally
speaking, the compound may contain atoms other than the carbon
atoms, such as hydrogen atoms and halogens. The preferred olefins
are ethylene, propylene, allyl chloride and mixtures of at least
two thereof.
[0013] The term "polyhydroxylated aliphatic hydrocarbon" refers to
a hydrocarbon which contains at least two hydroxyl groups attached
to two different saturated carbon atoms. The polyhydroxylated
aliphatic hydrocarbon may contain, but is not limited to, from 2 to
60 carbon atoms.
[0014] Each of the carbons of a polyhydroxylated aliphatic
hydrocarbon bearing the hydroxyl functional group (OH) cannot
possess more than one OH group and must have sp3 hybridization. The
carbon atom carrying the OH group may be primary, secondary or
tertiary. The polyhydroxylated aliphatic hydrocarbon used in the
present invention must contain at least two sp3-hybridized carbon
atoms carrying an OH group. The polyhydroxylated aliphatic
hydrocarbon includes any hydrocarbon containing a vicinal diol
(1,2-diol) or a vicinal triol (1,2,3-triol), including the higher,
vicinal or contiguous orders of these repeating units. The
definition of the polyhydroxylated aliphatic hydrocarbon also
includes, for example, one or more 1,3-, 1,4-, 1,5- and 1,6-diol
functional groups. The polyhydroxylated aliphatic hydrocarbon may
also be a polymer such as polyvinyl alcohol. Geminal diols, for
example, are excluded from this class of polyhydroxylated aliphatic
hydrocarbons.
[0015] The polyhydroxylated aliphatic hydrocarbons may contain
aromatic moieties or heteroatoms, including, for example,
heteroatoms of halogen, sulphur, phosphorus, nitrogen, oxygen,
silicon and boron type, and mixtures thereof.
[0016] Polyhydroxylated aliphatic hydrocarbons which can be used in
the present invention comprise, for example, 1,2-ethanediol
(ethylene glycol), 1,2-propanediol (propylene glycol),
1,3-propanediol, 1-chloro-2,3-propanediol (chloropropanediol),
2-chloro-1,3-propanediol (chloropropanediol), 1,4-butanediol,
1,5-pentanediol, cyclohexanediols, 1,2-butanediol,
1,2-cyclo-hexanedimethanol, 1,2,3-propanetriol (also known as
"glycerol" or "glycerin"), and mixtures thereof. With preference
the polyhydroxylated aliphatic hydrocarbon used in the present
invention includes, for example, 1,2-ethanediol, 1,2-propanediol,
1,3-propanediol, chloropropanediol and 1,2,3-propanetriol, and
mixtures of at least two thereof. More preferably the
polyhydroxylated aliphatic hydrocarbon used in the present
invention includes, for example, 1,2-ethanediol, 1,2-propanediol,
chloropropanediol and 1,2,3-propanetriol, and mixtures of at least
two thereof. 1,2,3-Propanetriol or glycerol is the most
preferred.
[0017] The esters of the polyhydroxylated aliphatic hydrocarbon may
be present in the polyhydroxylated aliphatic hydrocarbon and/or may
be produced in the process for preparing the chlorohydrin and/or
may be prepared prior to the process for preparing the
chlorohydrin. Examples of esters of the polyhydroxylated aliphatic
hydrocarbon comprise ethylene glycol monoacetate, propanediol
monoacetates, glycerol monoacetates, glycerol monostearates,
glycerol diacetates and mixtures thereof.
[0018] The term "chlorohydrin" is used here in order to describe a
compound containing at least one hydroxyl group and at least one
chlorine atom attached to different saturated carbon atoms. A
chlorohydrin which contains at least two hydroxyl groups is also a
polyhydroxylated aliphatic hydrocarbon. Accordingly the starting
material and the product of the reaction may each be chlorohydrins.
In that case the "product" chlorohydrin is more chlorinated than
the starting chlorohydrin, in other words has more chlorine atoms
and fewer hydroxyl groups than the starting chlorohydrin. Preferred
chlorohydrins are chloroethanol, chloropropanol, chloropropanediol,
dichloropropanol and mixtures of at least two thereof.
Dichloropropanol is particularly preferred. Chlorohydrins which are
more particularly preferred are 2-chloroethanol,
1-chloropropan-2-ol, 2-chloropropan-1-ol, 1-chloropropane-2,3-diol,
2-chloropropane-1,3-diol, 1,3-dichloropropan-2-ol,
2,3-dichloropropan-1-ol and mixtures of at least two thereof.
[0019] The polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon, or the mixture thereof in
the process according to the invention may be obtained starting
from fossil raw materials or starting from renewable raw materials.
It is preferable for at least part to be obtained starting from
renewable raw materials. It is preferable for at least part to be
obtained starting from fossil raw materials.
[0020] The polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof may
be subjected to a purification treatment so as to reduce the amount
of salts and/or of organic compounds other than the
polyhydroxylated aliphatic hydrocarbon or the ester of
polyhydroxylated aliphatic hydrocarbon before the chlorination
process.
[0021] By fossil raw materials are meant materials obtained from
the processing of petrochemical natural resources, such as
petroleum, natural gas and coal, for example. Among these materials
preference is given to organic compounds containing 2 and 3 carbon
atoms. When the polyhydroxylated aliphatic hydrocarbon is glycerol,
allyl chloride, allyl alcohol and "synthetic" glycerol are
particularly preferred. By "synthetic" glycerol is meant a glycerol
generally obtained from petrochemical resources. When the
polyhydroxylated aliphatic hydrocarbon is ethylene glycol, ethylene
and "synthetic" ethylene glycol are particularly preferred. By
"synthetic" ethylene glycol is meant an ethylene glycol generally
obtained from petrochemical resources. When the polyhydroxylated
aliphatic hydrocarbon is propylene glycol, propylene and
"synthetic" propylene glycol are particularly preferred. By
"synthetic" propylene glycol is meant a propylene glycol generally
obtained from petrochemical resources.
[0022] By renewable raw materials are meant materials obtained from
the processing of renewable natural resources. Among these
materials preference is given to "natural" ethylene glycol,
"natural" propylene glycol and "natural" glycerol. "Natural"
ethylene glycol, propylene glycol and glycerol are obtained for
example by conversion of sugars by thermochemical processes for
example, it being possible for these sugars to be obtained starting
from biomass, as described in "Industrial Bioproducts: Today and
Tomorrow", Energetics, Incorporated for the U.S. Department of
Energy, Office of Energy Efficiency and Renewable Energy, Office of
the Biomass Program, July 2003, pages 49, 52 to 56. One of these
processes is, for example, the catalytic hydrogenolysis of sorbitol
obtained by thermochemical conversion of glucose. Another process
is, for example, the catalytic hydrogenolysis of xylitol obtained
by hydrogenation of xylose. The xylose may for example be obtained
by hydrolysis of the hemicellulose present in maize fibres. By
"glycerol obtained from renewable raw materials" is meant, in
particular, glycerol obtained during the production of biodiesel or
else glycerol obtained during conversions of animal or vegetable
oils or fats in general, such as saponification,
transesterification or hydrolysis reactions.
[0023] Among the oils which can be used in the process of the
invention, mention may be made of all common oils, such as palm
oil, palm kernel oil, copra oil, babassu oil, former or new (low
erucic acid) colza oil, sunflower oil, maize oil, castor oil and
cotton oil, peanut oil, soya bean oil, linseed oil and crambe oil,
and all oils obtained, for example, from sunflower plants or colza
plants obtained by genetic modification or hybridization.
[0024] It is also possible to employ used frying oils, various
animal oils, such as fish oils, tallow, lard and even squaring
greases.
[0025] Among the oils used mention may also be made of oils which
have been partly modified by means, for example, of polymerization
or oligomerization, such as, for example, the "stand oils" of
linseed oil and of sunflower oil, and blown vegetable oils.
[0026] A particularly suitable glycerol may be obtained during the
conversion of animal fats. Another particularly suitable glycerol
may be obtained during the production of biodiesel. A third, very
suitable glycerol may be obtained during the conversion of animal
or vegetable oils or fats by transesterification in the presence of
a heterogeneous catalyst, as described in documents FR 2752242, FR
2869612 and FR 2869613. More specifically, the heterogeneous
catalyst is selected from mixed oxides of aluminium and zinc, mixed
oxides of zinc and titanium, mixed oxides of zinc, titanium and
aluminium, and mixed oxides of bismuth and aluminium, and the
heterogeneous catalyst is employed in the form of a fixed bed. This
latter process can be a process for producing biodiesel.
[0027] In the process for preparing an epoxide according to the
invention, the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof may
be as described in the patent application entitled "Process for
preparing chlorohydrin by converting polyhydroxylated aliphatic
hydrocarbons", filed in the name of SOLVAY SA on the same day as
the present application, and the content of which is incorporated
here by reference.
[0028] Particular mention is made of a process for preparing a
chlorohydrin wherein a polyhydroxylated aliphatic hydrocarbon, an
ester of a polyhydroxylated aliphatic hydrocarbon or a mixture
thereof whose total metal content, expressed in elemental form, is
greater than or equal to 0.1 .mu.g/kg and less than or equal to
1000 mg/kg is reacted with a chlorinating agent.
[0029] In a first aspect of the process according to the invention,
at least a fraction of the chlorohydrin may be prepared by a
process of hypochlorinating an olefin. The olefin may be selected
from ethylene, propylene, allyl chloride and mixtures thereof.
[0030] In a second aspect of the process according to the
invention, at least a fraction of the chlorohydrin may be prepared
by a process of chlorinating an unsaturated aliphatic alcohol. The
term "unsaturated aliphatic alcohol" refers to a hydrocarbon which
contains at least one hydroxyl group and a carbon-carbon double
bond. The unsaturated aliphatic alcohol may contain, but is not
limited to, from 2 to 60 carbon atoms. Allyl alcohol is an example
of unsaturated alcohol.
[0031] In a third aspect of the process according to the invention,
at least part of the epoxide may be prepared by a process of
epoxidizing an olefin. The epoxidation may be carried out employing
any desired peroxide. Among inorganic peroxides preference is given
to perborates, percarbonates and hydrogen peroxide, with hydrogen
peroxide being particularly preferred. Organic peroxides, organic
hydroperoxides, and the adduct of hydrogen peroxide with urea may
also be used.
[0032] The different aspects of the process according to the
invention may be combined with one another.
[0033] In the process for preparing an epoxide according to the
invention, the employment of the chlorohydrin obtained starting
from the polyhydroxylated aliphatic hydrocarbon, the ester of the
polyhydroxylated aliphatic hydrocarbon or the mixture thereof, by
reaction with a chlorinating agent, may be effected, for example,
by the process described in application WO 2005/054167 of SOLVAY
SA, the content of which is incorporated here by reference.
[0034] In the process for preparing an epoxide according to the
invention, the polyhydroxylated aliphatic hydrocarbon, the ester of
the polyhydroxylated aliphatic hydrocarbon or the mixture thereof
may be a crude product or a purified product, as described in
application WO 2005/054167 of SOLVAY SA, from page 2 line 8 to page
4 line 2.
[0035] In the process for preparing an epoxide according to the
invention, the polyhydroxylated aliphatic hydrocarbon, the ester of
the polyhydroxylated aliphatic hydrocarbon or the mixture thereof
may have an alkali metal and/or alkaline earth metal content of
less than or equal to 5 g/kg, as described in the application
entitled "Process for preparing a chlorohydrin by chlorinating a
polyhydroxylated aliphatic hydrocarbon", filed in the name of
SOLVAY SA on the same day as the present application, and whose
content is incorporated here by reference.
[0036] In the process according to the invention, the alkali metal
and/or alkaline earth metal content of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof is less than or equal to 5 g/kg,
often less than or equal to 1 g/kg, more particularly less than or
equal to 0.5 g/kg and in certain cases less than or equal to 0.01
g/kg. The alkali metal and/or alkaline earth metal content of the
glycerol is generally greater than or equal to 0.1 .mu.g/kg.
[0037] In the process according to the invention the alkali metals
are generally lithium, sodium, potassium and cesium, often sodium
and potassium, and frequently sodium.
[0038] In the process for preparing a chlorohydrin according to the
invention, the lithium content of the polyhydroxylated aliphatic
hydrocarbon, the ester of polyhydroxylated aliphatic hydrocarbon or
the mixture thereof is generally less than or equal to 1 g/kg,
often less than or equal to 0.1 g/kg and more particularly less
than or equal to 2 mg/kg. This content is generally greater than or
equal to 0.1 .mu.g/kg.
[0039] In the process according to the invention, the sodium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0040] In the process according to the invention, the potassium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0041] In the process according to the invention, the rubidium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0042] In the process according to the invention, the cesium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0043] In the process according to the invention the alkaline earth
metal elements are generally magnesium, calcium, strontium and
barium, often magnesium and calcium and frequently calcium.
[0044] In the process according to the invention, the magnesium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0045] In the process according to the invention, the calcium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0046] In the process according to the invention, the strontium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0047] In the process according to the invention, the barium
content of the polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof is
generally less than or equal to 1 g/kg, often less than or equal to
0.1 g/kg and more particularly less than or equal to 2 mg/kg. This
content is generally greater than or equal to 0.1 .mu.g/kg.
[0048] In the process according to the invention, the alkali and/or
alkaline earth metals are generally present in the form of salts,
frequently in the form of chlorides, sulphates and mixtures
thereof. Sodium chloride is the most often encountered.
[0049] In the process for preparing an epoxide according to the
invention, the chlorinating agent of the polyhydroxylated aliphatic
hydrocarbon, of the ester of polyhydroxylated aliphatic hydrocarbon
or of the mixture thereof may be hydrogen chloride and/or
hydrochloric acid, as described in application WO 2005/054167 of
SOLVAY SA, from page 4 line 30 to page 6 line 2.
[0050] Particular mention is made of a chlorinating agent which may
be aqueous hydrochloric acid or hydrogen chloride which is
preferably anhydrous. The hydrogen chloride may originate from a
process of pyrolysing organic chlorine compounds, such as, for
example, from the preparation of vinyl chloride, from a process for
preparing 4,4-methylenediphenyl diisocyanate (MDI) or toluene
diisocyanate (TDI), from metal pickling processes or from a
reaction of an inorganic acid such as sulphuric or phosphoric acid
with a metal chloride such as sodium chloride, potassium chloride
or calcium chloride.
[0051] In one advantageous embodiment of the process for preparing
an epoxide according to the invention, the chlorinating agent is
gaseous hydrogen chloride or an aqueous solution of hydrogen
chloride, or a combination of the two.
[0052] In the process for preparing an epoxide according to the
invention, the chlorinating agent of the polyhydroxylated aliphatic
hydrocarbon, of the ester of polyhydroxylated aliphatic hydrocarbon
or of the mixture thereof may be aqueous hydrochloric acid or
hydrogen chloride which is preferably anhydrous, as obtained from a
process for preparing allyl chloride and/or chloromethanes and/or a
process of chlorinolysis and/or of high-temperature oxidation of
chlorine compounds, as described in the application entitled
"Process for preparing a chlorohydrin by reacting a
polyhydroxylated aliphatic hydrocarbon with a chlorinating agent",
filed in the name of SOLVAY SA on the same day as the present
application, and the content of which is incorporated here by
reference. The hydrogen chloride may be gaseous hydrogen chloride
and/or an aqueous solution of hydrogen chloride.
[0053] Particular mention is made of a process for preparing a
chlorohydrin from a polyhydroxylated aliphatic hydrocarbon, from an
ester of a polyhydroxylated aliphatic hydrocarbon or from a mixture
thereof, and from a chlorinating agent, the chlorinating agent
comprising at least one of the following compounds: nitrogen,
oxygen, hydrogen, chlorine, an organic hydrocarbon compound, an
organic halogen compound, an organic oxygen compound and a
metal.
[0054] Particular mention is made of an organic hydrocarbon
compound which is selected from saturated and unsaturated aliphatic
and aromatic hydrocarbons and mixtures thereof.
[0055] Particular mention is made of an unsaturated aliphatic
hydrocarbon which is selected from acetylene, ethylene, propylene,
butene, propadiene, methylacetylene and mixtures thereof, of a
saturated aliphatic hydrocarbon which is selected from methane,
ethane, propane, butane and mixtures thereof and of an aromatic
hydrocarbon which is benzene.
[0056] Particular mention is made of an organic halogen compound
which is an organic chlorine compound selected from chloromethanes,
chloroethanes, chloropropanes, chlorobutanes, vinyl chloride,
vinylidene chloride, monochloropropenes, perchloroethylene,
trichloroethylene, chlorobutadienes, chlorobenzenes and mixtures
thereof.
[0057] Particular mention is made of an organic halogen compound
which is an organic fluorine compound selected from fluoromethanes,
fluoroethanes, vinyl fluoride, vinylidene fluoride and mixtures
thereof.
[0058] Particular mention is made of an organic oxygen compound
which is selected from alcohols, chloroalcohols, chloroethers and
mixtures thereof.
[0059] Particular mention is made of a metal selected from alkali
metals, alkaline earth metals, iron, nickel, copper, lead, arsenic,
cobalt, titanium, cadmium, antimony, mercury, zinc, selenium,
aluminium, bismuth and mixtures thereof.
[0060] Mention is made more particularly of a process wherein the
chlorinating agent is obtained at least partly from a process for
preparing allyl chloride and/or a process for preparing
chloromethanes and/or a process of chlorinolysis and/or a process
for oxidizing chlorine compounds at a temperature greater than or
equal to 800.degree. C.
[0061] In one advantageous embodiment of the process for preparing
the epoxide according to the invention, the chlorinating agent of
the polyhydroxylated aliphatic hydrocarbon, of the ester of
polyhydroxylated aliphatic hydrocarbon or of the mixture thereof
does not contain gaseous hydrogen chloride.
[0062] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in a reactor
as described in application WO 2005/054167 of SOLVAY SA on page 6
lines 3 to 23.
[0063] Mention is made particularly of a plant made from or covered
with materials which are resistant, under the reaction conditions,
to chlorinating agents, in particular to hydrogen chloride. Mention
is made more particularly of a plant made of enamelled steel or of
tantalum.
[0064] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of the polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in apparatus
which is made of or covered with materials that are resistant to
chlorinating agents, as described in the application "Process for
preparing a chlorohydrin in corrosion-resistant apparatus", filed
in the name of SOLVAY SA on the same day as the present
application, and the content of which is incorporated here by
reference.
[0065] Particular mention is made of a process for preparing a
chlorohydrin that includes a step in which a polyhydroxylated
aliphatic hydrocarbon, an ester of a polyhydroxylated aliphatic
hydrocarbon or a mixture thereof is subjected to reaction with a
chlorinating agent containing hydrogen chloride and to at least one
other step carried out in an apparatus made of or covered with
materials resistant to the chlorinating agent, under the conditions
in which that step is realized. Mention is made more particularly
of metallic materials such as enamelled steel, gold and tantalum
and of non-metallic materials such as high-density polyethylene,
polypropylene, poly(vinylidene fluoride), polytetrafluoroethylene,
perfluoroalkoxyalkanes and poly(perfluoropropyl vinyl ether),
polysulphones and polysulphides, and unimpregnated and impregnated
graphite.
[0066] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in a reaction
medium as described in the application entitled "Continuous process
for preparing chlorohydrins", filed in the name of SOLVAY SA on the
same day as the present application, and the content of which is
incorporated here by reference.
[0067] Particular mention is made of a continuous process for
producing chlorohydrin in which a polyhydroxylated aliphatic
hydrocarbon, an ester of a polyhydroxylated aliphatic hydrocarbon
or a mixture thereof is reacted with a chlorinating agent and an
organic acid in a liquid reaction medium whose steady-state
composition comprises polyhydroxylated aliphatic hydrocarbon and
esters of polyhydroxylated aliphatic hydrocarbon for which the sum
of the amounts, expressed in moles of polyhydroxylated aliphatic
hydrocarbon, is greater than 1.1 mol % and less than or equal to 30
mol %, the percentage being based on the organic part of the liquid
reaction medium.
[0068] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in the
presence of a catalyst as described in application WO 2005/054167
of SOLVAY SA from page 6 line 28 to page 8 line 5.
[0069] Mention is made particularly of a catalyst based on a
carboxylic acid or on a carboxylic acid derivative having an
atmospheric boiling point of greater than or equal to 200.degree.
C., especially adipic acid and derivatives of adipic acid.
[0070] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out at a catalyst
concentration, temperature and pressure and for residence times as
described in application WO 2005/054167 of SOLVAY SA from page 8
line 6 to page 10 line 10.
[0071] Mention is made particularly of a temperature of at least
20.degree. C. and not more than 160.degree. C., of a pressure of at
least 0.3 bar and not more than 100 bar and of a residence time of
at least 1 h and not more than 50 h.
[0072] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in the
presence of a solvent as described in application WO 2005/054167 of
SOLVAY SA at page 11 lines 12 to 36.
[0073] Mention is made particularly of organic solvents such as a
chlorinated organic solvent, an alcohol, a ketone, an ester or an
ether, a non-aqueous solvent which is miscible with the
polyhydroxylated aliphatic hydrocarbon, such as chloroethanol,
chloropropanol, chloropropanediol, dichloropropanol, dioxane,
phenol, cresol and mixtures of chloropropanediol and
dichloropropanol, or heavy products of the reaction such as at
least partially chlorinated and/or esterified oligomers of the
polyhydroxylated aliphatic hydrocarbon.
[0074] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in the
presence of a liquid phase comprising heavy compounds other than
the polyhydroxylated aliphatic hydrocarbon, as described in the
application entitled "Process for preparing a chlorohydrin in a
liquid phase", filed in the name of SOLVAY SA on the same day as
the present application, and the content of which is incorporated
here by reference.
[0075] Particular mention is made of a process for preparing a
chlorohydrin wherein a polyhydroxylated aliphatic hydrocarbon, an
ester of polyhydroxylated aliphatic hydrocarbon or a mixture
thereof is subjected to reaction with a chlorinating agent in the
presence of a liquid phase comprising heavy compounds other than
the polyhydroxylated aliphatic hydrocarbon and having a boiling
temperature under a pressure of 1 bar absolute of at least
15.degree. C. more than the boiling temperature of the chlorohydrin
under a pressure of 1 bar absolute.
[0076] In the process for preparing an epoxide according to the
invention, the reaction of chlorinating the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may be carried out in batch mode
or in continuous mode. The continuous mode is particularly
preferred.
[0077] In the process for preparing an epoxide according to the
invention, the chlorination reaction of the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof is preferably carried out in a
liquid reaction medium. The liquid reaction medium may be a
single-phase or multi-phase medium.
[0078] The liquid reaction medium is composed of all of the
dissolved or dispersed solid compounds, dissolved or dispersed
liquid compounds and dissolved or dispersed gaseous compounds at
the temperature of the reaction.
[0079] The reaction medium comprises the reactants, the catalyst,
the solvent, the impurities present in the reactants, in the
solvent and in the catalyst, the reaction intermediates, the
products and the by-products of the reaction.
[0080] By reactants are meant the polyhydroxylated aliphatic
hydrocarbon, the ester of polyhydroxylated aliphatic hydrocarbon
and the chlorinating agent.
[0081] Among the impurities present in the polyhydroxylated
aliphatic hydrocarbon mention may be made of carboxylic acids,
salts of carboxylic acids, esters of fatty acid with the
polyhydroxylated aliphatic hydrocarbon, esters of fatty acids with
the alcohols used in the transesterification, and inorganic salts
such as alkali metal or alkaline earth metal sulphates and
chlorides.
[0082] When the polyhydroxylated aliphatic hydrocarbon is glycerol,
the impurities in the glycerol that may be mentioned include
carboxylic acids, salts of carboxylic acids, fatty acid esters such
as mono-, di- and triglycerides, esters of fatty acids with the
alcohols used in the transesterification and inorganic salts such
as alkali metal or alkaline earth metal sulphates and
chlorides.
[0083] Among the reaction intermediates mention may be made of
monochlorohydrins of the polyhydroxylated aliphatic hydrocarbon and
their esters and/or polyesters, the esters and/or polyesters of the
polyhydroxylated aliphatic hydrocarbon and the esters of
polychlorohydrins.
[0084] When the chlorohydrin is dichloropropanol, the reaction
intermediates that may be mentioned include glycerol
monochlorohydrin and its esters and/or polyesters, the esters
and/or polyesters of glycerol and the esters of
dichloropropanol.
[0085] The ester of polyhydroxylated aliphatic hydrocarbon may
therefore be, at each instance, a reactant, an impurity of the
polyhydroxylated aliphatic hydrocarbon or a reaction
intermediate.
[0086] By products of the reaction are meant the chlorohydrin and
water. The water may be the water formed in the chlorination
reaction and/or water introduced into the process, for example via
the polyhydroxylated aliphatic hydrocarbon and/or the chlorinating
agent, as described in application WO 2005/054167 of SOLVAY SA at
page 2 lines 22 to 28 to page 3 lines 20 to 25, at page 5 lines 7
to 31 and at page 12 lines 14 to 19.
[0087] Among the by-products mention may be made for example of the
partially chlorinated and/or esterified oligomers of the
polyhydroxylated aliphatic hydrocarbon.
[0088] When the polyhydroxylated aliphatic hydrocarbon is glycerol,
the by-products that may be mentioned include, for example, the
partially chlorinated and/or esterified oligomers of glycerol.
[0089] The reaction intermediates and the by-products may be formed
in the different steps of the process, such as, for example, during
the step of preparing the chlorohydrin and during the steps of
separating off the chlorohydrin.
[0090] The liquid reaction medium may therefore contain the
polyhydroxylated aliphatic hydrocarbon, the chlorinating agent in
solution or dispersion in the form of bubbles, the catalyst, the
solvent, the impurities present in the reactants, the solvent and
the catalyst, such as dissolved or solid salts, for example, the
reaction intermediates, the products and the by-products of the
reaction.
[0091] In the preparation process according to the invention, the
reaction of the polyhydroxylated aliphatic hydrocarbon, the ester
of polyhydroxylated aliphatic hydrocarbon or the mixture thereof
with the chlorinating agent may take place in the presence of an
organic acid. The organic acid may be a product originating from
the process for preparing the polyhydroxylated aliphatic
hydrocarbon or a product not originating from this process. In this
latter case the product in question may be an organic acid which is
used in order to catalyse the reaction of the polyhydroxylated
aliphatic hydrocarbon with the hydrogen chloride, and/or an acid
generated in the process of preparing the chlorohydrin.
Consideration is given, for example, to acids generated starting
from aldehydes which are present in the polyhydroxylated aliphatic
hydrocarbon or formed during the preparation of the chlorohydrin.
The organic acid may also be a mixture of an organic acid
originating from the process for preparing the polyhydroxylated
aliphatic hydrocarbon, and of an organic acid not originating from
the process for preparing the polyhydroxylated aliphatic
hydrocarbon.
[0092] In the process according to the invention, the esters of the
polyhydroxylated aliphatic hydrocarbon may originate from the
reaction between the polyhydroxylated aliphatic hydrocarbon and the
organic acid, before, during or within the steps which follow the
reaction with the chlorinating agent.
[0093] In the process according to the invention, the separation of
the chlorohydrin and of the other compounds from the reaction
medium may be carried out in accordance with the methods as
described in application WO 2005/054167 of SOLVAY SA from page 12
line 1 to page 16 line 35 and page 18 lines 6 to 13. These other
compounds are those mentioned above and include unconsumed
reactants, the impurities present in the reactants, the catalyst,
the solvent, the reaction intermediates, the water and the
by-products of the reaction.
[0094] Particular mention is made of separation by azeotropic
distillation of a water/chlorohydrin/chlorinating agent mixture
under conditions which minimize the losses of chlorinating agent,
followed by isolation of the chlorohydrin by decantation.
[0095] In the process according to the invention, the isolation of
the chlorohydrin and of the other compounds from the reaction
medium may be carried out in accordance with methods of the kind
described in patent application EP 05104321.4, filed in the name of
SOLVAY SA on May 20, 2005 and the content of which is incorporated
here by reference. A separation method including at least one
separating operation intended to remove the salt from the liquid
phase is particularly preferred.
[0096] Particular mention is made of a process for preparing a
chlorohydrin by reacting a polyhydroxylated aliphatic hydrocarbon,
an ester of a poly-hydroxylated aliphatic hydrocarbon or a mixture
thereof with a chlorinating agent wherein the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof that is used comprises at least
one solid or dissolved metal salt, the process including a
separation operation intended to remove part of the metal salt.
Mention is made more particularly of a process for preparing a
chlorohydrin by reacting a polyhydroxylated aliphatic hydrocarbon,
an ester of a polyhydroxylated aliphatic hydrocarbon or a mixture
thereof with a chlorinating agent wherein the polyhydroxylated
aliphatic hydrocarbon that is used comprises at least one chloride
and/or a sodium and/or potassium sulphate and in which the
separating operation intended to remove part of the metal salt is a
filtering operation. Particular mention is also made of a process
for preparing a chlorohydrin wherein (a) a polyhydroxylated
aliphatic hydrocarbon, an ester of a polyhydroxylated aliphatic
hydrocarbon or a mixture thereof is subjected to reaction with a
chlorinating agent in a reaction mixture, (b) continuously or
periodically, a fraction of the reaction mixture containing at
least water and the chlorohydrin is removed, (c) at least a part of
the fraction obtained in step (b) is introduced into a distillation
step and (d) the reflux ratio of the distillation step is
controlled by providing water to the said distillation step.
Mention is made very particularly of a process for preparing a
chlorohydrin wherein (a) a polyhydroxylated aliphatic hydrocarbon,
an ester of a polyhydroxylated aliphatic hydrocarbon or a mixture
thereof is subjected to reaction with hydrogen chloride in a
reaction mixture, (b) continuously or periodically, a fraction of
the reaction mixture containing at least water and chlorohydrin is
removed, (c) at least part of the fraction obtained in step (b) is
introduced into a distillation step in which the ratio between the
hydrogen chloride concentration and the water concentration in the
fraction introduced into the distillation step is smaller than the
hydrogen chloride/water concentration ratio in the binary
azeotropic hydrogen chloride/water composition at the distillation
temperature and pressure.
[0097] In the process for preparing the epoxide according to the
invention, the separation of the chlorohydrin and of the other
compounds from the reaction medium from chlorination of the
polyhydroxylated aliphatic hydrocarbon may be carried out in
accordance with methods as described in the application entitled
"Process for preparing a chlorohydrin" filed in the name of SOLVAY
SA on the same day as the present application and the content of
which is incorporated here by reference.
[0098] Particular mention is made of a process for preparing a
chlorohydrin which comprises the following steps: (a) a
polyhydroxylated aliphatic hydrocarbon, an ester of a
polyhydroxylated aliphatic hydrocarbon or a mixture thereof is
reacted with a chlorinating agent and an organic acid so as to give
a mixture containing the chlorohydrin and esters of the
chlorohydrin, (b) at least part of the mixture obtained in (a) is
subjected to one or more treatments subsequent to step (a), and (c)
the polyhydroxylated aliphatic hydrocarbon is added to at least one
of the steps subsequent to step (a), in order to react at a
temperature greater than or equal to 20.degree. C. with the esters
of the chlorohydrin, so as to form, at least partly, esters of the
polyhydroxylated aliphatic hydrocarbon. Mention is made more
particularly of a process in which the polyhydroxylated aliphatic
hydrocarbon is glycerol and the chlorohydrin is
dichloropropanol.
[0099] In the process for preparing the epoxide according to the
invention, the separation of the chlorohydrin and the other
compounds from the reaction medium from chlorination of the
polyhydroxylated aliphatic hydrocarbon may be carried out in
accordance with methods as described in the application entitled
"Process for preparing a chlorohydrin starting from a
polyhydroxylated aliphatic hydrocarbon", filed in the name of
SOLVAY SA on the same day as the present application, and the
content of which is incorporated here by reference.
[0100] Particular mention is made of a process for preparing
chlorohydrin by reacting a polyhydroxylated aliphatic hydrocarbon,
an ester of a polyhydroxylated aliphatic hydrocarbon or a mixture
thereof with a chlorinating agent in a reactor which is supplied
with one or more liquid streams containing less than 50% by weight
of the polyhydroxylated aliphatic hydrocarbon, of the ester of
polyhydroxylated aliphatic hydrocarbon or of the mixture thereof
relative to the weight of the entirety of the liquid streams
introduced into the reactor. More particular mention is made of a
process comprising the following steps: (a) a polyhydroxylated
aliphatic hydrocarbon, an ester of a polyhydroxylated aliphatic
hydrocarbon or a mixture thereof is reacted with a chlorinating
agent so as to give at least one mixture containing the
chlorohydrin, water and the chlorinating agent, (b) at least a
fraction of the mixture formed in step (a) is removed, and (c) the
fraction removed in step (b) is subjected to an operation of
distillation and/or stripping wherein the polyhydroxylated
aliphatic hydrocarbon is added in order to isolate, from the
fraction removed in step (b), a mixture containing water and the
chlorohydrin and exhibiting a reduced chlorinating agent content as
compared with the fraction removed in step (b).
[0101] In the process for preparing the epoxide according to the
invention, the separation of the chlorohydrin and of the other
compounds from the reaction medium from chlorination of the
polyhydroxylated aliphatic hydrocarbon may be carried out in
accordance with methods as described in the application entitled
"Process for converting polyhydroxylated aliphatic hydrocarbons
into chlorohydrins", filed in the name of SOLVAY SA on the same day
as the present application, and the content of which is
incorporated here by reference.
[0102] Particular mention is made of a process for preparing a
chlorohydrin that comprises the following steps: [0103] (a) A
polyhydroxylated aliphatic hydrocarbon, an ester of a
polyhydroxylated aliphatic hydrocarbon or a mixture thereof is
reacted with a chlorinating agent so as to give a mixture
containing the chlorohydrin, chlorohydrin esters and water. [0104]
(b) At least a fraction of the mixture obtained in step (a) is
subjected to a distillation and/or stripping treatment so as to
give a portion concentrated in water, in chlorohydrin and in
chlorohydrin esters. [0105] (c) At least a fraction of the portion
obtained in step (b) is subjected to a separating operation in the
presence of at least one additive so as to obtain a moiety
concentrated in chlorohydrin and in chlorohydrin esters and
containing less than 40% by weight of water.
[0106] The separating operation is more particularly a
decantation.
[0107] In the process according to the invention, the isolation and
the treatment of the other compounds of the reaction medium may be
carried out in accordance with methods as described in the
application entitled "Process for preparing a chlorohydrin by
chlorinating a polyhydroxylated aliphatic hydrocarbon", filed in
the name of SOLVAY SA on the same day as the present application. A
preferred treatment consists in subjecting a fraction of the
by-products of the reaction to a high-temperature oxidation.
[0108] Particular mention is made of a process for preparing a
chlorohydrin that comprises the following steps: (a) a
polyhydroxylated aliphatic hydrocarbon, an ester of a
polyhydroxylated aliphatic hydrocarbon or a mixture thereof whose
alkali metal and/or alkaline earth metal content is less than or
equal to 5 g/kg, an chlorinating agent and an organic acid are
reacted so as to give a mixture containing at least the
chlorohydrin and by-products, (b) at least a portion of the mixture
obtained in step (a) is subjected to one or more treatments in
steps subsequent to step (a), and (c) at least one of the steps
subsequent to step (a) consists in an oxidation at a temperature
greater than or equal to 800.degree. C. More particular mention is
made of a process wherein, in the subsequent step, a portion of the
mixture obtained in step (a) is removed and this portion is
subjected to oxidation at a temperature greater than or equal to
800.degree. C. in the course of the removal. Particular mention is
also made of a process wherein the treatment of step (b) is a
separating operation selected from decantation, filtration,
centrifugation, extraction, washing, evaporation, stripping,
distillation, and adsorption operations or the combinations of at
least two of these operations.
[0109] In the process according to the invention, when the
chlorohydrin is chloropropanol, it is generally employed in the
form of a mixture of compounds comprising the isomers of
1-chloropropan-2-ol and 2-chloropropan-1-ol. This mixture generally
contains more than 1% by weight of the two isomers, preferably more
than 5% by weight and particularly more than 50%. The mixture
commonly contains less than 99.9% by weight of the two isomers,
preferably less than 95% by weight and more particularly less than
90% by weight. The other constituents of the mixture may be
compounds originating from the processes for preparing the
chloropropanol, such as residual reactants, reaction by-products,
solvents and, in particular, water.
[0110] The mass ratio of the isomers, 1-chloropropan-2-ol and
2-chloropropan-1-ol, is commonly greater than or equal to 0.01,
preferably greater than or equal to 0.4. This ratio is commonly
less than or equal to 99 and preferably less than or equal to
25.
[0111] In the process according to the invention, when the
chlorohydrin is chloroethanol, it is generally employed in the form
of a mixture of compounds comprising the 2-chloroethanol isomer.
This mixture generally contains more than 1% by weight of the
isomer, preferably more than 5% by weight and particularly more
than 50%. The mixture commonly contains less than 99.9% by weight
of the isomer, preferably less than 95% by weight and more
particularly less than 90% by weight. The other constituents of the
mixture may be compounds originating from the processes for
preparing the chloroethanol, such as residual reactants, reaction
by-products, solvents and, in particular, water.
[0112] In the process according to the invention, when the
chlorohydrin is dichloropropanol, it is generally employed in the
form of a mixture of compounds comprising the isomers of
1,3-dichloropropan-2-ol and 2,3-dichloropropan-1-ol. This mixture
generally contains more than 1% by weight of the two isomers,
preferably more than 5% by weight and in particular more than 50%.
The mixture commonly contains less than 99.9% by weight of the two
isomers, preferably less than 95% by weight and more particularly
less than 90% by weight. The other constituents of the mixture may
be compounds originating from the processes for preparing the
dichloropropanol, such as residual reactants, reaction by-products,
solvents and, in particular, water.
[0113] The mass ratio between the 1,3-dichloropropan-2-ol and
2,3-dichloropropan-1-ol isomers is commonly greater than or equal
to 0.01, often greater than or equal to 0.4, frequently greater
than or equal to 1.5, preferably greater than or equal to 3.0, more
preferably greater than or equal to 7.0 and with very particular
preference greater than or equal to 20.0. This ratio is commonly
less than or equal to 99 and preferably less than or equal to
25.
[0114] In the process according to the invention, when the
chlorohydrin is dichloropropanol and is obtained in a process
starting from allyl chloride, the mixture of isomers has a
1,3-dichloropropan-2-ol: 2,3-dichloropropan-1-ol mass ratio which
is often from 0.3 to 0.6, typically approximately 0.5. When the
dichloropropanol is obtained in a process starting from synthetic
and/or natural glycerol, the 1,3-dichloropropan-2-ol:
2,3-dichloropropan-1-ol mass ratio is commonly greater than or
equal to 1.5, preferably greater than or equal to 3.0 and in
particular greater than or equal to 7.0. When the dichloropropanol
is obtained starting from allyl alcohol, the
1,3-dichloropropan-2-ol: 2,3-dichloropropan-1-ol mass ratio is
often of the order of 0.1.
[0115] In the process according to the invention, the step of
purifying the epoxide may be preceded by at least one step of
chemically treating the epoxide. This chemical treating may be
washing of the epoxide with an aqueous solution of a metal
salt.
[0116] In the process according to the invention, the step of
purifying the epoxide may comprise at least one distillation
step.
[0117] In the process for preparing an organic product according to
the invention, the process of chlorinating the polyhydroxylated
aliphatic hydrocarbon generally comprises a plurality of steps and
preferably (a) at least one step of reacting a polyhydroxylated
aliphatic hydrocarbon, an ester of polyhydroxylated aliphatic
hydrocarbon or a mixture thereof with the chlorinating agent,
optionally in the presence of an organic acid as catalyst, to give
a mixture containing the chlorohydrin and water, and (b) at least
one step of stripping and/or distilling at least one first fraction
of the mixture obtained in step (a) so as to give a first mixture
concentrated with chlorohydrin and with water. With particular
preference the process of chlorinating the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof comprises (I) at least one step
of decantation of the concentrated mixture obtained in step (b) so
as to give at least one first aqueous phase concentrated with water
and a first organic phase concentrated with chlorohydrin.
[0118] In the process for preparing an organic product according to
the invention, the process of chlorinating the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may comprise (c) at least one
additional step of stripping and/or distilling a second fraction of
the mixture obtained in step (a) so as to give at least one second
mixture concentrated with chlorohydrin and with water. With
particular preference the process of chlorinating the
polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon or the mixture thereof
comprises (II) at least one step of decantation of the concentrated
mixture obtained in step (c) so as to give at least one second
aqueous phase concentrated with water and one second organic phase
concentrated with chlorohydrin.
[0119] In the process for preparing an organic product according to
the invention, the process of chlorinating the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may comprise (d) at least one
additional step of hydrolytically treating a third fraction of the
mixture obtained in step (a) so as to regenerate the acidic
catalyst.
[0120] In the process for preparing an organic product according to
the invention, the process of chlorinating the polyhydroxylated
aliphatic hydrocarbon, the ester of polyhydroxylated aliphatic
hydrocarbon or the mixture thereof may comprise (e) at least one
additional step of oxidative treatment at a temperature greater
than or equal to 800.degree. C. of a fourth fraction of the mixture
obtained in step (a) so as to give a gaseous mixture containing the
chlorinating agent.
[0121] The chlorohydrin obtained in the process according to the
invention may include a heightened amount of halogenated ketones,
in particular of chloroacetone, as described in patent application
FR 05.05120 of May 20, 2005, filed in the name of the applicant,
and the content of which is incorporated here by reference. The
halogenated ketone content may be reduced by subjecting the
chlorohydrin obtained in the process according to the invention to
an azeotropic distillation in the presence of water or by
subjecting the chlorohydrin to a dehydrochlorination treatment as
described in this application from page 4 line 1 to page 6 line
35.
[0122] Particular mention is made of a process for preparing an
epoxide wherein halogenated ketones are formed as by-products and
which comprises at least one treatment of removal of at least a
portion of the halogenated ketones formed. Mention is made more
particularly of a process for preparing an epoxide by
dehydrochlorinating a chlorohydrin of which at least one fraction
is prepared by chlorinating a polyhydroxylated aliphatic
hydrocarbon, an ester of a polyhydroxylated aliphatic hydrocarbon
or a mixture thereof, a treatment of dehydrochlorination and a
treatment by azeotropic distillation of a water/halogenated ketone
mixture, which are intended to remove at least a portion of the
halogenated ketones formed, and a process for preparing
epichlorohydrin wherein the halogenated ketone formed is
chloroacetone.
[0123] The process for preparing an organic product according to
the invention comprises optionally (f) a step of treating the
chlorohydrin so as to reduce its halogenated ketone content.
[0124] The chlorohydrin obtained in the process according to the
invention may be subjected to a dehydrochlorination reaction in
order to produce an epoxide, as described in patent applications WO
2005/054167 and FR 05.05120, both filed in the name of SOLVAY
SA.
[0125] The dehydrochlorination of the chlorohydrin may be carried
out as described in the application entitled "Process for preparing
an epoxide starting from a polyhydroxylated aliphatic hydrocarbon
and a chlorinating agent", filed in the name of SOLVAY SA on the
same day as the present application, and the content of which is
incorporated here by reference.
[0126] Particular mention is made of a process for preparing an
epoxide wherein a reaction medium resulting from the reaction
between a polyhydroxylated aliphatic hydrocarbon, an ester of a
polyhydroxylated aliphatic hydrocarbon or a mixture thereof with a
chlorinating agent, the reaction medium containing at least 10 g of
chlorohydrin per kg of reaction medium, is subjected to a
subsequent chemical reaction without intermediate treatment.
[0127] Mention is also made of the preparation of an epoxide that
comprises the following steps: [0128] (a) A polyhydroxylated
aliphatic hydrocarbon, an ester of a polyhydroxylated aliphatic
hydrocarbon or a mixture thereof is reacted with a chlorinating
agent and an organic acid so as to form the chlorohydrin and
chlorohydrin esters in a reaction medium containing the
polyhydroxylated aliphatic hydrocarbon, the ester of
polyhydroxylated aliphatic hydrocarbon, water, the chlorinating
agent and the organic acid, the reaction medium containing at least
10 g of chlorohydrin per kg of reaction medium. [0129] (b) At least
a fraction of the reaction medium obtained in step (a), this
fraction having the same composition as the reaction medium
obtained in step (a), is subjected to one or more treatments in
steps subsequent to step (a). [0130] (c) A basic compound is added
to at least one of the steps subsequent to step (a) in order to
react at least partly with the chlorohydrin, the chlorohydrin
esters, the chlorinating agent and the organic acid so as to form
the epoxide and salts.
[0131] The process for preparing an epoxide according to the
invention comprises at least one process for purifying aqueous
and/or organic liquid effluents which have come from the
constituent processes. These purification processes may be
physical, such as, for example, processes of filtration,
decantation, adsorption, stripping, distillation, ion exchange, or
chemical, such as, for example, processes of oxidation, reduction,
precipitation, complexation, of acidic or basic treatment, or may
be biological. For the treatment of aqueous liquid effluents
preference is given to chemical and biological processes. A
chemical treatment by chlorination in a basic medium, preferably at
a pH of between 7 and 12, at a temperature of between 100 and
150.degree. C. and for durations of 0.5 to 7 h is particularly
preferred.
[0132] The process for preparing an epoxide according to the
invention comprises at least one process for purifying gaseous
effluents which have come from the constituent processes. These
purification processes may be physical, such as, for example,
processes of washing, condensation, or adsorption, or chemical,
such as, for example, oxidations, reductions, precipitations,
complexations, and acidic or basic treatments. Treatment of the
gaseous effluents by high-temperature oxidation in a stream of air
or oxygen is preferred.
[0133] In the process according to the invention, the olefin is
preferably allyl chloride, the polyhydroxylated aliphatic
hydrocarbon is preferably glycerol and the chlorohydrin is
preferably dichloropropanol and the epoxide is preferably
epichlorohydrin.
[0134] The process according to the invention may be followed by a
process for preparing products derived from ethylene oxide, such as
ethylene glycol, di- and polyethylene glycols, of mono-, di- and
triethanolamines, products derived from propylene oxide, such as
propylene 1,2-glycol, dipropylene glycol, propylene glycol ethers
and isopropylamines, and products derived from epichlorohydrin,
such as glycerol, epoxy resins, synthetic elastomers, glycidyl
ethers and polyamide resins.
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