METHOD FOR PRODUCING E-I-CHLORO-3,3,3-TRIFLUOROPROPENE
FROM 1,1,3,3-TETRACHLOROPROPENE
5
FIELD OF THE INVENTION
The present invention relates to a process for the continuous
manufacture of E-I-chloro-3,3,3-trifluoropropene (E-1233zd) comprising at least
one stage of liquid-phase fluorination of 1 , I ,3,3-tetrachloropropene (1230za).
10 Another subject matter of the present invention is a plant suitable for the
implementation of this process on the industrial scale.
TECHNICAL BACKGROUND
E-I-chloro-3,3,3-trifluoropropene (E-1233zd) can be manufactured by
15 fluorination of 1 , I ,I ,3,3-pentachloropropane (240fa). For example, the
documents US 8 436 217 and US 8 426 656 describe the fluorination of 240fa
to give E-1233zd in the liquid phase in the presence of suitable catalysts, such
as TiCI4 ora~ombinationo f TiCI4 and SbC15.
The document FR 2 768 727 also teaches that the fluorination of 240fa or
20 1230za can be carried out in the presence of a catalyst, such as TiCI4.
The documents US2010/0191025 and US 6 166 274 also describe the
use of a catalyst for the liquid-phase fluorination of 1230za in order to obtain
E-1233zd: a catalyst based on ionic liquid for the first document and a triflic or
trifluoroacetic acid for the second document.
25 The document US 2012/0059199 describes the liquid-phase fluorination
of 240fa in the absence of a catalyst. This document teaches that one
disadvantage of the uncatalyzed liquid-phase process is the low degree of
conversion of the reaction. Several reactors in series are thus necessary in
order to increase the overall degree of conversion, each of the reactors making
30 its contribution to the advancement of the degree of conversion.
The document US 20131021 1154 describes the use of a high reaction
pressure in combination with a stirred fluorination reactor in order to be able to
increase the degree of conversion of 240fa in an uncatalyzed liquid-phase
process. However, there is no information on the degree of conversion.
35 The document US 6 987 206 describes the possibility of obtaining
E-1233zd from 1230za as intermediate without indication of operating
conditions.
The uncatalyzed liquid-phase reaction for the fluorination of 1230za is
exemplified in the document US 5 616 819. The pressure used is 200 psi
(14 bar) and results in the formation of oligomers, despite the short duration of
the batch test.
5 The document US 5 877 359 presents the uncatalyzed liquid-phase
fluorination of 1230za. The examples show that a very high molar ratio of 166
was used in order to obtain a complete conversion on a short-duration batch
test. When the molar ratio is reduced to 12.6, a pressure of 600 psig (42 bar) is
applied. Furthermore, the operating conditions of an extrapolatable continuous
10 process are thus not defined: HF11230za molar ratio, reflux temperature, nature
of the byproducts to be distilled. The productivity or the stability over time of a
process based on this reaction are not described either.
There still exists a need to develop a novel process for the continuous
and extrapolatable production of E-1233zd while avoiding restrictive operating
15 conditions, such as an excessive pressure, a high molar ratio or stirring in the
fluorination reactor which might result in a loss in selectivity by formation of
oligomers or overfluorinated products.
, -
SUMMARY OF THE INVENTION
20 The present invention makes it possible to overcome the disadvantages
of the state of the art. It more particularly provides a novel process for
production of E-I-chloro-3,3,3-trifluoropropene.
This is accomplished by virtue of the simplified implementation of the
fluorination of 1230za to give E-1233zd by hydrogen fluoride in the liquid phase
25 in the absence of catalyst.
Another subject matter of the present invention is an industrial process
for the manufacture of E-I-chloro-3,3,3-trifluoropropene including the various
separation and recycling operations.
An additional subject matter of the present invention is a plant which
30 makes it possible to carry out the various embodiments of the process.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
The invention is now described in more detail and without implied
limitation in the description which follows.
According to the present invention, the process comprises at least one
5 stage during which 1 , I ,3,3-tetrachloropropene reacts with anhydrous
hydrofluoric acid in the liquid phase in the absence of catalyst with an
HF/1,1,3,3-tetrachloropropene molar ratio of between 3 and 20, at a
temperature of between 50 and 150°C and an absolute pressure of between I
and 20 bar.
10 Another subject matter of the present invention is a process for the
manufacture of E-I-chloro-3,3,3-trifluoropropene comprising (i) at least one
stage during which 1 , I ,3,3-tetrachloropropene reacts with anhydrous
hydrofluoric acid in the liquid phase in a reactor provided with a bleed and with
an effluent outlet; (ii) at least one stage of treatment of the effluent resulting
15 from the reactor to give a stream A comprising E-1-chloro-3,3,3-
trifluoropropene, HCI, HF and Z-I-chloro-3,3,3-trifluoropropene and a stream B
predominantly comprising HF (for example, at least 50% by weight, preferably
at least 70% by weight, of HF); (iii) at least one stage of recovery of the
hydrochloric acid from the stream A to give a stream C of HCI and a stream D
20 comprising E-I-chloro-3,3,3-trifluoropropene, HCI, HF and Z-I-chloro-3,3,3-
trifluoropropene; (iv) at least one stage of purification of the stream D resulting
from stage (iii) to give E-1233zd, preferably with a purity of greater than or equal
to 98%, advantageously of greater than or equal to 99% and very
advantageously of greater than or equal to 99.9% by weight.
25 An additional subject matter of the present invention is a process for the
manufacture of E-I-chloro-3,3,3-trifluoropropene comprising (i) at least one
stage during which 1,1,3,3-tetrachloropropene reacts with anhydrous
hydrofluoric acid in the liquid phase in a reactor in the absence of catalyst with
an HF/1,1,3,3-tetrachloropropene molar ratio of between 3 and 20, at a
30 temperature between 50 and 150°C and an absolute pressure between 1 and
20 bar, (ii) at least one stage of treatment of the effluent resulting from the
reactor to give a stream A comprising E-I-chloro-3,3,3-trifluoropropene, HCI,
HF and Z-1-chloro-3,3,3-trifluoropropene and a stream B predominantly
comprising HF (for example, at least 50% by weight, preferably at least 70% by
35 weight, of HF); (iii) at least one stage of recovery of the hydrochloric acid from
the stream A to give a stream C of HCI and a stream D comprising E-l-chloro-
3,3,3-trifluoropropene, HCI, HF and Z-1-chloro-3,3,3-trifluoropropene; (iv) at
least one stage of purification of the stream D resulting from stage (iii) to give
E-1233zd, preferably with a purity of greater than or equal to 98%,
advantageously of greater than or equal to 99% and very advantageously of
greater than or equal to 99.9% by weight.
5 Preferably, before the purification stage, the stream D resulting from
stage (iii) is subjected to at least one separation stage in order to give a stream
comprising mainly HF (for example at least 90% by weight, preferably at least
98% by weight and advantageously at least 99% by weight of HF) which can be
recycled to the reactor and a stream comprising E-1-chloro-3,3,3-
10 trifluoropropene, HCI, HF and Z-I-chloro-3,3,3-trifluoropropene.
The separation stage is preferably a separation by settling, carried out at
a temperature advantageously of between -50 and 50°C, preferably between
-20°C and 10°C.
The treatment stage (ii) is preferably a reflux column, advantageously
15 employed at a temperature of between 30 and 120°C, in order to give the
condensable stream B which is recycled to the reactor.
The recovery of HCI in stage (iii) is preferably obtained using a distillation
column provided.with a-reboiler at the bottom and with a reflux system at the
top. The bottom temperature is advantageously between 20 and 110°C. The top
20 temperature is advantageously between -50 and 0°C. The distillation of the HCI
is typically carried out at a pressure of between 7 and 25 bar.
Preferably, the composition of the stream D resulting from the stage of
separation in the HF after the stage (iii) comprises approximately 90-95%
E-1233zd, 3-5% HF, 1-5% Z-1233zd and 0.1-2% of coproducts and
25 intermediate products.
According to one embodiment, the purification stage (iv) preferably
comprises at least one distillation stage and advantageously at least two
distillation stages. According to a preferred embodiment, the purification stage
(iv) comprises at least one stage of washing with water andlor of washing using
30 a basic solution, a drying stage and at least one distillation stage. The aim of
this distillation stage is to remove the light products and also the heavy products
which may be partially recycled to the reactor, depending on whether or not
they can be recycled. The stream A can additionally comprise organic
compounds, such as the intermediates from the fluorination reaction or
35 coproducts. Mention may in particular be made of dichlorodifluoropropene,
trichloromonofluoropropene, fluorotetrachloropropane, pentafluoropropane,
difluorotrichloropropane, dichlorotrifluoropropane and 1,3,3,3-
tetrafluoropropene.
The process according to the present invention can additionally comprise
a bleeding stage, which bleed, after treatment, can be recycled to the reactor.
5 The HFII ,I ,3,3-tetrachloropropene molar ratio is preferably between 5
and 15, preferably between 6 and 15, more preferably still between 8 and 15,
advantageously between 9 and 14 and preferably between 9 and 12. The
HFII ,I ,3,3-tetrachloropropene molar ratio includes the recycled HF portion and
is preferably measured at the inlet of the reactor. The presence of an excess of
10 HF with respect to the organic compound makes it possible to rapidly discharge
the E-1233zd formed by azeotropic entrainment and thus makes it possible to
avoid the consecutive formation of overfluorinated products, such as, in
particular, 1,3,3,3-tetrafluoropropene, or 1234ze, and I ,I ,I ,3,3-
pentafluoropropane, or 245fa. The purity of the final product is thus improved by
15 virtue of the decrease in the amount of impurities formed from the reaction
stage.
The reaction temperature is preferably between 80 and 120°C and
advantageousiy between90 and 110°C.
The fluorination reaction is preferably carried out at a pressure of
20 between 5 and 20 bar, preferably between 5 and 15 bar, more preferably still
between 7 and 15 bar and advantageously between 7 and 12 bar. The
fluorination reaction is preferably carried out in an unstirred reactor.
The process according to the present invention can be carried out
continuously, noncontinuously or batchwise. It is preferable to operate
25 continuously.
The process according to the present invention offers the advantage of
obtaining a highly advantageous yield and a highly advantageous selectivity
while using mild conditions. In addition, these results can be obtained using a
single reactor.
30 Preferably, when reference is made to intervals, the expressions "of
between ... and ..." and "between ... and ..." exclude the limits of the interval
EMBODIMENT OF THE INVENTION
Figure 1 diagrammatically represents an embodiment of the process
35 according to the invention and a plant for its implementation.
Unless otherwise mentioned, all of the percentages indicated below are
percentages by weight.
The invention provides for the fluorination of 1230za to give E-1233zd by
hydrogen fluoride in the liquid phase, in the absence of catalyst.
5 With reference to figure 1, the plant according to the invention comprises
a catalytic reactor 3 for the implementation of the reaction for the fluorination of
1230za to give E-1233zd.
The reactor 3 is fed via a pipe for conveying 1 ,I ,3,3-tetrachloropropene 2
and a pipe for conveying hydrogen fluoride 1. Heating means are preferably
10 provided in order to preheat the reactants before their arrival in the reactor 3.
The abovementioned conveying pipes can feed the reactor 3 separately
or else can be connected together upstream of the reactor in order to feed the
latter with a mixture of reactants.
The reactor 3 is preferably a metal reactor. The metal of the reactor can
15 be steel or stainless steel. However, other materials, such as a superaustenitic
stainless steel or an alloy based on passivable nickel, can be used. The
absence of catalyst for the reaction is an advantage which makes it possible to
avoid corrosim~@ienomena known to a person skilled in the art when a
fluorination catalyst is used in this type of reactor.
20 All of the other items of equipment of the plant and in particular all of the
separation columns or distillation columns can be made of metal.
The reactor 3 can comprise a heating jacket which makes it possible to
bring the reaction mixture to the desired temperature between 50 and 15O0C,
preferably between 80 and 120°C and advantageously between 90 and 110°C.
25 A withdrawal pipe makes it possible to bleed off an amount of
undesirable products of high molecular weight which could have been formed
during the fluorination reaction. This stream also contains HF and organic
compounds recoverable in value which are separated by a specific treatment 5
before being returned to the reactor. This treatment involves technologies
30 known to a person skilled in the art, such as separation by settling or azeotropic
distillation and preferably a combination of the two. The stream 16 corresponds
to the heavy compounds not recoverable in value, which have to be removed
from the process.
A pipe for withdrawing products resulting from the reaction is connected
35 to the outlet of the reactor 3. This pipe transports a stream containing the
desired product (E-1233zd), hydrogen chloride, hydrogen fluoride and
coproducts and byproducts of the reaction.
The pipe for withdrawing products resulting from the reaction feeds a
preliminary separation unit 4, which is preferably a distillation column provided
with a top reflux system. This preliminary separation unit ensures a first
separation of HF from the remainder of the products resulting from the reaction.
5 A first intermediate pipe is connected at the top of the preliminary
separation unit 4, which pipe is intended to collect the remaining products
resulting from the reaction and feeds a separation unit 6 intended for the
separation of the hydrogen chloride, which is a coproduct of the reaction. The
composition resulting from the intermediate separation unit 4 typically
10 comprises 43% E-1233zd, 15-18% HF and 35-40% HCI, the remainder
consisting of Z-1233zd, (Z+E)-1234ze, 243fc, 245fa and 1232 and/or 1231
isomers.
Cooling means can be provided on the first intermediate pipe so that the
first separation unit operates at the desired temperature.
15 The separation unit 6 is preferably a distillation column provided with a
bottom reboiler and with a top reflux system. It can, for example, be operated at
a pressure slightly lower than that of the reactor 3. A pipe for withdrawing
hydrogen chloride is connected at the top of the first separation unit, via which
pipe a stream 7 predominantly comprising hydrogen chloride is withdrawn.
20 Traces of E-1233zd or of light coproducts, such as 245fa or E-1234ze, may be
present in this stream.
The HCI produced is preferably recovered in value in the form of HCI
solution after adiabatic or isothermal absorption in water. The HCI can be
purified by passing the gas through alumina towers in order to have a desired
25 analytical grade.
A separation system 3 is connected to the bottom of the separation unit
6, which separation system will make possible the separation of the HF - and the
other organic products. The composition resulting from the separation unit 6
typically comprises between 25 and 30% of HF, 70% of E-1233zd and between
30 1 and 5% of byproduct compounds from the reaction. This separation system
can consist of a first phase separation unit consisting of a decanter, employed
at a temperature advantageously of between -50 and 50°C, preferably between
-20 and 10°C. The phase rich in HF can thus be conveyed to a separation unit
which is preferably an azeotropic distillation column, the fraction of which at the
35 column bottom is enriched in HF, before being recycled to the reactor 3 along
the pipe 9 (99.7% HF, 0.3% E-1233zd). The azeotropic fraction 10 collected at
the top (69% E-1233zd, 27% HF, the remainder being composed of HCI and of
traces of other organics) is recycled to the separation unit 8.
The phase rich in organic compounds will be collected via the pipe 11
and can be treated, according to figure 1, by a downstream line of a purification
5 unit 12 comprising at least one additional azeotropic distillation column which
makes it possible to finalize the separation of HF and a final purification unit
which makes it possible to obtain the E-1233zd with a purity of greater than or
equal to 98% (stream 14 of figure 1). Preferably, before the purification stage,
the phase resulting from the separation unit 8 has a composition of
10 approximately 90.95% E-1233zd, 3-5% HF, 1-5% Z-1233zd and 0.1-2%
coproducts and intermediate products.
According to one embodiment, the process comprises two specified
azeotropic distillations: an azeotropic column incorporated in the separation
system 8 after the decanter and an azeotropic column in the purification unit 12.
15 The purification unit 12 preferably comprises a first distillation column for
removing the light products (245fa, E-1234ze or residual traces of HCI) which
are discharged from the process via the pipe 13.
Thegas stream resulting from this first distillation is subsequently treated
by an azeotropic column in order to finalize the separation of HF. An azeotropic
20 composition is thus collected in the pipe 17 and recycled to the separation unit
8. The composition of this stream is similar to that of the stream from - the pipe
10, that is to say an azeotropic mixture of HF and E-1233zd.
The resulting gas stream is finally treated by at least one purification
column, preferably two columns, in order to remove a fraction predominantly
25 comprising the cis-1233zd isomer and intermediate compounds (for example
the 1231, 1232, 241, 242 and 243 isomers, and the like), which are recycled to
the reactor via the pipe 15, and another fraction containing compounds not
recoverable in value (heavy products, 1223xd, and the like), which are removed
via the pipe 18.
30 The final product E-1233zd is subsequently collected via the pipe 14 with
a purity of greater than or equal to 98%, advantageously of greater than or
equal to 99% and very advantageously of greater than or equal to 99.9% by
weight.
According to a preferred embodiment referenced in figure 2, the phase
35 rich in organic compounds will be collected via the pipe 11 (approximately
90.95% E-1233zd, 3.5% HF, 1-5% Z-1233zd and 0.1-2% of coproducts and
intermediate products) and can be treated by a system for washing by
absorption l2, followed by a final removal stage 13 which makes it possible to
finalize the separation of HF and to obtain the E-1233zd with a purity of greater
than or equal to 98% (stream 14 of figure 2).
The washing system 2 preferably consists of a first washing with water
5 which makes it possible to absorb the residual HF. The temperature of this
washing 'operation is maintained above the dew point of the organic mixture.
The washing system is supplemented subsequently by a second washing
column ,fed with a caustic solution (KOH, NaOH, and the like) which makes it
possible to finalize the neutralization of the stream. The organic stream is
10 subsequently dried (for example using molecular sieves) and then condensed
before being conducted to the final purification line.
On conclusion of this washing operation, the composition of the stream
no longer contains HF and the distribution of the organic compounds is typically
as follows: 93-94% of E-1233zd, 3.5-4% of Z-1233zd isomer, 1% of 1232zd,
15 less than 1% of 1234ze and less than 1% of 245fa.
The purification unit 13 preferably comprises a first distillation column for
removing light products (245fa, E-1234ze), which are discharged from the
process via thep pipe ~+J, . ..: ....,
The resulting gas stream is finally treated by at least one purification
20 column, preferably two columns, in order to remove a fraction predominantly
comprising the cis-1233zd isomer and intermediate compounds (for example
the 1231, 1232, 241, 242 and 243 isomers, and the like), which are recycled to
the reactor via the pipe 15, and another fraction containing compounds not
recoverable in value (heavy products, 1223xd, and the like), which are removed
25 via the pipe 18.
The final product E-1233zd is subsequently collected via the pipe 14 with
a purity of greater than or equal to 98%, advantageously of greater than or
equal to 99% and very advantageously of greater than or equal to 99.9% by
weight.
30
EXAMPLES
The following examples illustrate the invention without limiting it.
A first stage consists in preparing the starting material. 1,1,3,3-
35 Tetrachloropropene is obtained by dehydrochlorination of I ,I , I ,3,3-
pentachloropropane in the presence of anhydrous ferric chloride.
Example 1: Preparation of 1230za by dehydrochlorination of 240fa
1441.6 g of 1 , I ,I ,3,3-pentachloropropane, with a purity of 99.6%, are
introduced into a glass reactor equipped with a jacket and with a reflux
condenser. The head space of the reactor is flushed with a nitrogen flow of 4 Ilh
5 in order to render the atmosphere inert. 14.4 g of anhydrous ferric chloride are
subsequently introduced before starting the stirring at 800 revolutionslmin. The
reflux condenser is fed with a fluid maintained at 20°C. The outlet gas from the
condenser is connected to a water bubbler which makes it possible to trap the
HCI which is given off during the dehydrochlorination reaction. The mixture is
10 subsequently heated between 75 and 80°C for several hours (approximately 4
hours) until the release of gas is ceased. 1195.6 g of resulting solution are
emptied from the round-bottomed flask. The mixture obtained is filtered in order
to remove the suspended ferric chloride and then analyzed by gas
chromatography.
czcls 1 0.051 1 0.052
240db 10.157 10.159
Table 1- Dehydrochlorination of 240fa: composition of the mixture
Compound (mol%) 1 Before reaction I After reaction
Example 2: Distillation of the 1230za
The 1230za of low purity is subsequently subjected to a conventional
20 laboratory distillation involving a column having 10 plates, a reflux condenser, a
vacuum pump, a .round-bottomed flask and round-bottomed receivers. The
distillation is carried out under a vacuum of 25 mbar; the product 1230za then
has a boiling point of 53°C. A starting material of good purity is obtained which
has the following composition: 99.33% 1230za, 0.02% 250fa, 0.15% 240fa,
25 0.009% C2Cls and 0.001% 240db.
1230za
Example 3: Continuous liquid-phase fluorination of the 1230za with a
molar ratio of 9 at the inlet of the reactor
The item of equipment used consists of a jacketed autoclave with a
30 capacity of 1 liter, manufactured from 316L stainless steel. It is provided with
0.055 92.613
means for measuring temperature and pressure. Openings in the top of the
autoclave make possible the introduction of the reactants and the removal of
the products. A condenser is provided at the top, and also a valve for regulating
the pressure. The condenser is temperature-controlled using an independent
5 thermostatically controlled bath. Its function is to return to the reactor a portion
of the unreacted HF and of the intermediates.
The products of the reaction are continuously extracted during the
reaction. The outlet gas stream passes through a washing device which collects
the hydracids HF and HCI and is then cooled in liquid nitrogen. The molar
10 distribution of the products of the outlet gas is analyzed periodically by GC (gas
chromatography).
At the end of the test, the reaction medium is depressurized and slowly
heated in order to discharge the residual HF. During this degasification period,
the organic compounds possibly entrained are also recovered, after passing
15 through the washing device in order to remove HF and HCI from the gas
stream. In a final stage, the autoclave is opened and emptied.
The-st&ing.material prepared in example 2 is used for a fluorination
reaction.
20 An amount of 300 g of HF is introduced into the autoclave. The
temperature of the reactor is adjusted to 92-93°C in the liquid phase. The
pressure is regulated at 10 bar abs. The reactants are subsequently introduced
with the following flow rates: 20 glh of 1230za and 20 glh of HF. The molar ratio
of HF to the organic compound is thus 9. The establishment of a correct
25 equilibrium by weight between the inlet and the outlet is regularly confirmed.
The composition of the outlet stream is monitored by GC analysis and is given
in table 2:
The amount of overfluorinated impurities 1234ze (E+Z) and 245fa
remains greater than 1% throughout the test.
5 The remainder of the composition consists of intermediate products
(1231, 1232, 242, 243) andlor of unidentified products.
Time
5.5 h
23 h
29.2 h
46.7 h
53.7 h
The productivity of the reaction system for F1233zd-E is 0.31 mollh/l
10 Example 4 - Continuous liquid-phase fluorination of the 1230za with a molar
ratio of betw6eri9 and 10 at the inlet of the reactor
The procedure of example 3 is repeated but while doubling the feed flow
rates of organic and of HF, i.e. 40 glh of 1230za and 40-44 glh of HF. The molar
ratio HF to the organic compound is between 9 and 10.
15
The composition of the outlet stream is monitored by GC analysis and is
given in table 3:
Molar composition at the outlet
F1233zd-E
90.6%
92.1%
91.6%
92.4%
92.1%
Table 2 - Molar composition of the outlet qas
The amount of overfluorinated impurities 1234ze (E+Z) and 245fa is
rapidly less than 1%.
The productivity of the reaction system for F1233zd-E is 0.68 mollhll.
:1230za inlet flow rate of 20 qlh)
Time
5.5 h
23.1 h
29.1 h
46.6 h
F1233zd-Z
3.9%
3.7%
3.7%
3.7%
3.6%
Table 3 - Molar composition of the outlet gas (1230za inlet flow rate of 40 qlh'
Molar composition at the outlet
F1234ze(E+Z)
1.4%
1.5%
1.6%
1.5%
1.6%
F1233zd-E
92.5%
93.7%
93.5%
91.4%
F245fa
2.2%
1.4%
1.4%
1.1%
1.2%
F1233zd-Z
3.8%
3.7%
3.8%
4.5%
F1234ze(E+Z)
1 .O%
0.6%
0.5%
0.2%
F245fa
1 .O%
0.7%
0.6%
0.1%
Following the tests described in examples 3 and 4, the reactor was
emptied. The hydracids were trapped in water, the light organics were trapped
under cold conditions and the remaining organics in the reactor bottom were
recovered. The liquid level in the reactor decreased during the test and the
5 composition of the reactor is as follows: 11.3 g of HF, 5.6 g of HCI, 9 g of light
organics and 127 g of organic compounds accumulated in the reactor. The
chromatographic analysis of these two fractions was carried out and made it
possible to reconstitute the overall composition of the liquid mixture as
percentage by weight: 7.4% HF, 3.7% HCI, 3.5% E-1233zd, 0.25% Z-1233zd,
10 18.2% 1230za, 2.4% 1231, 14.8% 1232 and 49.2% of unidentified compounds.
The conversion of the whole of the test is calculated on the basis of
27.9 g of 1230za encountered in the liquid phase, with respect to 3059 g
introduced in total, i.e. 99.1%. The selectivity for E-1233zd over the whole of the
15 continuous test (example 3 and example4) is 89.2%, the selectivity for
Z-1233zd is 3.8%, for 1232 2%, for 1234ze-E 0.7%, for 245fa 0.7% and for
unknown products 2.9%.
Example 5 - Continuous liquid-phase fluorination of the 1230za with a molar
20 ratio of 11
The procedure of example 3 is reproduced. An amount of 302 g of HF is
introduced ~nto the autoclave. The temperature of the reactor is adjusted to
90°C in the liquid phase. The pressure is regulated at 10 bar abs. The molar
ratio of HF to the organic compound is adjusted to 11 and a test of longer
25 duration was carried out in order to establish the stability of the continuous
process over 366 h. 50 glh of 1230za and 62 glh of HF are continuously
introduced. The establishment of a correct equilibrium by weight between the
inlet and the outlet is regularly conf~rmed.
The composition of the outlet stream is monitored by GC analysis and is
30 given in table 4:
Table 4 - Molar composition of the outlet qas (molar ratio 11, test of longer
duration)
The remainder oT the composition consists of intermediate products
(1231, 1232, 242, 243) andlor of unidentified products.
Following the tests described in example 5, the reactor was emptied. The
hydracids were trapped in water, the light organics were trapped under cold
conditions and the remaining organics in the reactor bottom were recovered. No
trace of 1230za could be detected. The conversion is thus 100%. The selectivity
for E-1233zd is 90-92%. The E-1233zd productivity is 0.9 mollhll.
229 g of organic substances were collected in the bottom of the reactor.
Considering that 17.6 kg of 1230za were fed in during the test, the production of
heavy products is calculated at only 1.3%.
The amount of overfluorinated impurities 1234ze (E+Z) and 245fa is less
than 1%.
Example 6 - Distillation of the crude E-1233zd
5
A batch of 902 g of crude product collected for a certain period of the
continuous test of example 5 was analyzed before being distilled. The
distillation column of Oldershaw type has twenty plates. The distillation is
carried out at atmospheric pressure. The product is charged cold (5°C) to the
10 boiler, which is gradually reheated so as to draw different fractions. The
analyses of the crude product and of the different fractions obtained are given in
table 5.
The purity of fraction 3 reaches a purity of greater than 99.9% with a simple
item of laboratory equipment. The 245fa in the final product does not exceed
40 ppm.
1232za
X
Table 5 - Purification of the crude E-1233zd by distillation
0.119
0.250
Nd
0.055
Nd
Nd
Nd
Nd
Nd
Nd
1. A process for the manufacture of E-I-chloro-3,3,3-trifluoropropene
comprising at least one stage during which 1 , I ,3,3-tetrachloropropene reacts
5 with anhydrous hydrofluoric acid in the liquid phase in the absence of catalyst
with an HFI1,1,3,3-tetrachloropropene molar ratio of between 3 and 20, at a
temperature of between 50 and 150°C and an absolute pressure of between 1
and 20 bar.
10 2. A process for the manufacture of E-I-chloro-3,3,3-trifluoropropene
comprising (i) at least one stage during which 1,1,3,3-tetrachloropropene reacts
with anhydrous hydrofluoric acid in the liquid phase in a reactor provided with a
bleed and with an effluent outlet; (ii) at least one stage of treatment of the
effluent resulting from the reactor to give a stream A comprising E-l-chloro-
15 3,3,3-trifluoropropene, HCI, HF and 2-I-chloro-3,3,3-trifluoropropene and a
stream B predominantly comprising HF; (iii) at least one stage of recovery of the
hydrochloric acid from the stream A to give a stream C of HCI and a stream D
comprising .E-4-chloro-3,3,3-trifluoropropene, HCI, HF and Z-1-chloro-3,3,3-
trifluoropropene; (iv) at least one stage of purification of the stream D resulting
20 from stage (iii) to give E-1233zd, preferably with a purity of greater than or equal
to 98%, advantageously of greater than or equal to 99% and very
advantageously of greater than or equal to 99.9% by weight.
3. The process as claimed in claim 1 or 2, characterized in that the
25 HFI1,1,3,3-tetrachloropropene molar ratio is between 3 and 20, preferably
between 5 and 15 and advantageously between 9 and 12.
4. The process as claimed in any one of the preceding claims,
characterized in that the temperature is between 50 and 150°C, preferably
30 between 80 and 120°C and advantageously between 90 and 110°C.
5. The process as claimed in any one of the preceding claims,
characterized in that the pressure is from 1 to 20 bar, preferably between 5 and
15 bar and advantageously between 7 and 12 bar.
6. The process as claimed in any one of the preceding claims,
characterized in that the fluorination reaction is carried out in an unstirred
reactor.
5 7. The process as claimed in any one of the preceding claims,
characterized in that the process is carried out continuously, noncontinuously or
batchwise, preferably continuously.
8. The process as claimed in any one of claims 2 to 7, characterized
10 in that, on conclusion of stage (iii), the stream D is subjected to a separation
stage in order to give a stream comprising mainly HF which can be recycled to
the reactor.
9. The process as claimed in claim 8, characterized in that the
15 separation stage is a separation by settling, preferably carried out between -50
and 50°C.
10. .T#epi~cess as claimed in any one of claims 2 to 9, characterized
in that the treatment stage (ii) is a reflux operation, preferably carried out
20 between 30 and 120°C.
11. The process as claimed in any one of claims 2 to 10,
characterized in that the stage of recovery of HCI is carried out at a temperature
of 20 to 110°C at the boiler bottom and -50 to 0°C at the top.
25
12. The process as claimed in any one of claims 2 to 11,
characterized in that the purification stage (iv) comprises at least one azeotropic
distillation.
30 13. The process as claimed in any one of claims 2 to 11,
characterized in that the purification stage (iv) comprises at least one washing
stage, a drying stage and at least one distillation stage.
14. A plant for the implementation of the process as claimed in any
35 one of the preceding claims.
15. A plant comprising a reactor 3 provided with at least two feed
pipes, with an effluent outlet connected to a reflux system 4, connected to an
HCL recovery unit 6, said unit 6 being connected to a separation system 8 with
the latter being connected to a purification system 2.