U.S. patent application number 12/396672 was filed with the patent office on 2009-09-10 for azeotrope-like composition of 2-chloro-3,3,3-trifluoropropene (hcfc-1233xf) and hydrogen fluoride (hf).
Invention is credited to Daniel C. Merkel, Hang T. Pham, Konstantin A. Pokrovski, Rajiv R. Singh, HsuehSung Tung.
Application Number | 20090224207 12/396672 |
Document ID | / |
Family ID | 41052664 |
Filed Date | 2009-09-10 |
United States Patent
Application |
20090224207 |
Kind Code |
A1 |
Pham; Hang T. ; et
al. |
September 10, 2009 |
Azeotrope-Like Composition of 2-Chloro-3,3,3-Trifluoropropene
(HCFC-1233xf) and Hydrogen Fluoride (HF)
Abstract
Provided are azeotropic and azeotrope-like compositions of
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and hydrogen fluoride
(HF). Such azeotropic and azeotrope-like compositions are useful as
intermediates in the production of 2,3,3,3-tetrafluoropropene
(HFO-1234yf).
Inventors: |
Pham; Hang T.; (Amherst,
NY) ; Merkel; Daniel C.; (West Seneca, NY) ;
Pokrovski; Konstantin A.; (Orchard Park, NY) ; Tung;
HsuehSung; (Getzville, NY) ; Singh; Rajiv R.;
(Getzville, NY) |
Correspondence
Address: |
HONEYWELL INTERNATIONAL INC.;PATENT SERVICES
101 COLUMBIA ROAD, P O BOX 2245
MORRISTOWN
NJ
07962-2245
US
|
Family ID: |
41052664 |
Appl. No.: |
12/396672 |
Filed: |
March 3, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61034184 |
Mar 6, 2008 |
|
|
|
Current U.S.
Class: |
252/372 |
Current CPC
Class: |
C07C 17/38 20130101;
C07C 17/383 20130101; C07C 17/206 20130101; C11D 7/50 20130101;
C11D 7/5054 20130101; C07C 21/18 20130101; C07C 17/383 20130101;
C07C 21/18 20130101 |
Class at
Publication: |
252/372 |
International
Class: |
C09K 3/00 20060101
C09K003/00 |
Claims
1. An azeotropic or azeotrope-like composition which consists
essentially of from about 6.2 mole percent to about 59.9 mole
percent hydrogen fluoride and from about 40.1 mole percent to about
93.8 mole percent 2-chloro-3,3,3-trifluoropropene, which
composition has a boiling point of from about 0.degree. C. to about
61.degree. C. at a pressure of from about 15 psia to about 107
psia.
2. The composition of claim 1 wherein the hydrogen fluoride is
present in the amount from about 53.5 mole percent to about 59.9
mole percent.
3. The composition of claim 1 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
40.1 mole percent to about 46.5 mole percent.
4. An azeotropic or azeotrope-like composition which consists
essentially of from about 71.8 mole percent to about 90.7 mole
percent hydrogen fluoride and from about 9.3 mole percent to about
28.2 mole percent 2-chloro-3,3,3-trifluoropropene, which
composition has a boiling point of from about 0.degree. C. to about
61.degree. C. at a pressure of from about 15 psia to about 107
psia.
5. The composition of claim 4 wherein the hydrogen fluoride is
present in the amount from about 71.8 to about 86.7 weight
percent.
6. The composition of claim 4 wherein the hydrogen fluoride is
present in the amount from about 71.8 to about 85.3 weight
percent.
7. The composition of claim 4 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
13.3 mole percent to about 28.2 mole percent.
8. The composition of claim 4 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
14.7 mole percent to about 28.2 mole percent.
9. A method of forming an azeotropic or azeotrope-like composition
which comprises forming a blend which consists essentially of from
about 6.2 mole percent to about 59.9 mole percent hydrogen fluoride
and from about 40.1 mole percent to about 93.8 mole percent
2-chloro-3,3,3-trifluoropropene.
10. The method of claim 9 wherein the hydrogen fluoride is present
in the amount from about 53.5 mole percent to about 59.9 mole
percent.
11. The method of claim 9 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
40.1 mole percent to about 46.5 mole percent.
12. The method of claim 9 further comprising the step of separating
2-chloro-3,3,3-trifluoropropene from an azeotropic or
azeotrope-like composition of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride using pressure swing distillation.
13. The method of claim 9 further comprising the step of feeding
the azeotropic or azeotrope-like composition of
2-chloro-3,3,3-trifluoropropene and hydrogen fluoride to a
fluorination reactor as a source of hydrogen fluoride.
14. A method of forming an azeotropic or azeotrope-like composition
which comprises forming a blend which consists essentially of from
about 71.8 mole percent to about 90.7 mole percent hydrogen
fluoride and from about 9.3 mole percent to about 28.2 mole percent
2-chloro-3,3,3-trifluoropropene.
15. The method of claim 14 wherein the hydrogen fluoride is present
in the amount from about 71.8 to about 86.7 weight percent.
16. The method of claim 14 wherein the hydrogen fluoride is present
in the amount from about 71.8 to about 85.3 weight percent.
17. The method of claim 14 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
13.3 mole percent to about 28.2 mole percent.
18. The method of claim 14 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
14.7 mole percent to about 28.2 mole percent.
19. The method of claim 14 further comprising the step of
separating 2-chloro-3,3,3-trifluoropropene from an azeotropic or
azeotrope-like composition of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride using pressure swing distillation.
20. The method of claim 14 further comprising the step of feeding
the azeotropic or azeotrope-like composition of
2-chloro-3,3,3-trifluoropropene and hydrogen fluoride to a
fluorination reactor as a source of hydrogen fluoride.
21. A method for removing 2-chloro-3,3,3-trifluoropropene from a
mixture containing 2-chloro-3,3,3-trifluoropropene and at least one
impurity, which comprises adding hydrogen fluoride to the mixture
in an amount sufficient to form an azeotropic or azeotrope-like
composition which consists essentially of from about 6.2 mole
percent to about 59.9 mole percent hydrogen fluoride and from about
40.1 mole percent to about 93.7 mole percent
2-chloro-3,3,3-trifluoropropene, and thereafter separating the
azeotropic composition from the impurity.
22. The method of claim 21 wherein the hydrogen fluoride is present
in the amount from about 53.5 mole percent to about 59.9 mole
percent.
23. The method of claim 21 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
40.1 mole percent to about 46.5 mole percent.
24. The method of claim 21 wherein the impurity does not form an
azeotropic mixture with 2-chloro-3,3,3-trifluoropropene, hydrogen
fluoride or a mixture of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride.
25. The method of claim 21 wherein the impurity does form an
azeotropic mixture with 2-chloro-3,3,3-trifluoropropene, hydrogen
fluoride or a mixture of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride.
26. The method of claim 21 wherein the impurity comprises a
halocarbon.
27. The method of claim 21 wherein the impurity is miscible with
2-chloro-3,3,3-trifluoropropene.
28. The method of claim 21 wherein the impurity comprises one more
of 1,1,1,2,3-pentachloropropane; 1,1,2,3-tetrachloropropene;
2,3,3,3-tetrafluoropropene; 2,3-dichloro-3,3-difluoropropene;
1,1,1,2,2-pentafluoropropane and
1,2-dichloro-3,3,3-trifluoropropene.
29. The method of claim 21 wherein the separating is conducted by
distillation.
30. A method for removing 2-chloro-3,3,3-trifluoropropene from a
mixture containing 2-chloro-3,3,3-trifluoropropene and at least one
impurity, which comprises adding hydrogen fluoride to the mixture
in an amount sufficient to form an azeotropic or azeotrope-like
composition which consists essentially of from about 71.8 mole
percent to about 90.7 mole percent hydrogen fluoride and from about
9.3 mole percent to about 28.2 mole percent
2-chloro-3,3,3-trifluoropropene, and thereafter separating the
azeotropic composition from the impurity.
31. The method of claim 30 wherein the hydrogen fluoride is present
in the amount from about 71.8 to about 86.7 weight percent.
32. The method of claim 30 wherein the hydrogen fluoride is present
in the amount from about 71.8 to about 85.3 weight percent.
33. The method of claim 30 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
13.3 mole percent to about 28.2 mole percent.
34. The method of claim 30 wherein the
2-chloro-3,3,3-trifluoropropene is present in the amount from about
14.7 mole percent to about 28.2 mole percent.
35. The method of claim 30 wherein the impurity does not form an
azeotropic mixture with 2-chloro-3,3,3-trifluoropropene, hydrogen
fluoride or a mixture of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride.
36. The method of claim 30 wherein the impurity does form an
azeotropic mixture with 2-chloro-3,3,3-trifluoropropene, hydrogen
fluoride or a mixture of 2-chloro-3,3,3-trifluoropropene and
hydrogen fluoride.
37. The method of claim 30 wherein the impurity comprises a
halocarbon.
38. The method of claim 30 wherein the impurity is miscible with
2-chloro-3,3,3-trifluoropropene.
39. The method of claim 30 wherein the impurity comprises one more
of 1,1,1,2,3-pentachloropropane; 1,1,2,3-tetrachloropropene;
2,3,3,3-tetrafluoropropene; 2,3-dichloro-3,3-difluoropropene;
1,1,1,2,2-pentafluoropropane and
1,2-dichloro-3,3,3-trifluoropropene.
40. The method of claim 30 wherein the separating is conducted by
distillation.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
patent application Ser. No. 61/034,184, filed Mar. 6, 2008, which
is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to azeotropic and
azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene
(HCFO-1233xf) and hydrogen fluoride (HF). More particularly the
invention pertains to such azeotropic and azeotrope-like
compositions which are useful as intermediates in the production of
2,3,3,3-tetrafluoropropene (HFO-1234yf).
[0004] 2. Description of the Prior Art
[0005] Traditionally, chlorofluorocarbons (CFCs) like
trichlorofluoromethane and dichlorodifluoromethane have been used
as refrigerants, blowing agents and diluents for gaseous
sterilization. In recent years there has been universal concern
that completely halogenated chlorofluorocarbons might be
detrimental to the Earth's ozone layer. Therefore,
stratospherically safer alternatives to these materials are
desirable. Consequently, there is a worldwide effort to use
fluorine-substituted hydrocarbons which contain fewer or no
chlorine substituents. In this regard,
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), having low ozone
depletion potential, is being considered as a replacement for
chlorofluorocarbons such as dichlorodifluoromethane in
refrigeration systems and trichlorofluoromethane as a blowing
agent. The production of HFC's, i.e. compounds containing only
carbon, hydrogen and fluorine has been the subject of interest to
provide environmentally desirable products for use as solvents,
blowing agents, refrigerants, cleaning agents, aerosol propellants,
heat transfer media, dielectrics, fire extinguishing compositions
and power cycle working fluids. It is known in the art to produce
fluorocarbons such as HFC's by reacting hydrogen fluoride with
various hydrochlorocarbon compounds. Such HFC's are not only
considered to be much more environmentally advantageous than
hydrochlorofluorocarbons (HCFC's) or chlorofluorocarbons (CFC's)
because they are not non-ozone depleting, but also they are
non-flammable, and non-toxic as compared to the chlorine containing
compounds.
[0006] HCFO-1233xf is an intermediate in the production of
2,3,3,3-tetrafluoropropene (HFO-1234yf) which is well known in the
art as described in U.S. Applications 20070007488 and 20070197842,
the specifications of which are incorporated herein by reference.
HFO-1234yf has been disclosed to be an effective refrigerant, heat
transfer medium, propellant, foaming agent, blowing agent, gaseous
dielectric, sterilant carrier, polymerization medium, particulate
removal fluid, carrier fluid, buffing abrasive agent, displacement
drying agent and power cycle working fluid.
[0007] It has now been found that an important intermediate in the
production of substantially pure HFO-1234yf, is an azeotropic or
azeotrope-like composition of 2-chloro-3,3,3-trifluoropropene
(HCFO-1233xf) and hydrogen fluoride. This intermediate, once
formed, may thereafter be separated into its component parts by
known extraction techniques. The azeotropic and azeotrope-like
compositions find use not only as intermediates in the production
of HFO-1234yf, but they are additionally useful as nonaqueous
etchant mixtures for etching semiconductors in the electronics
industry, as well as compositions for removing surface oxidation
from metals. In addition, the formation of an azeotropic or
azeotrope-like composition of HCFO-1233xf and hydrogen fluoride is
useful in separating a mixture of HCFO-1233xf and an impurity such
as a halocarbon, for example, 1,1,1,2,3-pentachloropropane;
1,1,2,3-tetrachloropropene; 2,3,3,3-tetrafluoropropene;
2,3-dichloro-3,3-difluoropropene; 1,1,1,2,2-pentafluoropropane; or
1,2-dichloro-3,3,3-trifluoropropene. When it is desired to separate
a mixture of HCFO-1233xf and an impurity, HF is added to form an
azeotropic mixture of HCFO-1233xf and hydrogen fluoride, and then
the impurity is removed from the azeotropic mixture, such as by
distillation or other known means. This binary azeotrope or
azeotrope-like composition is then available for separation into
its component parts.
SUMMARY OF THE INVENTION
[0008] The invention provides an azeotropic or azeotrope-like
composition which consists essentially of from about 6.2 mole
percent to about 59.9 mole percent hydrogen fluoride and from about
40.1 mole percent to about 93.8 mole percent
2-chloro-3,3,3-trifluoropropene. The composition has a boiling
point of from about 0.degree. C. to about 61.degree. C. at a
pressure of from about 15 psia to about 107 psia.
[0009] The invention further provides an azeotropic or
azeotrope-like composition which consists essentially of from about
71.8 mole percent to about 90.7 mole percent hydrogen fluoride and
from about 9.3 mole percent to about 28.2 mole percent
2-chloro-3,3,3-trifluoropropene. This composition has a boiling
point of from about 0.degree. C. to about 61.degree. C. at a
pressure of from about 15 psia to about 107 psia.
[0010] The invention also provides a method of forming an
azeotropic or azeotrope-like composition which comprises forming a
blend which consists essentially of from about 6.2 mole percent to
about 59.9 mole percent hydrogen fluoride and from about 40.1 mole
percent to about 93.8 mole percent
2-chloro-3,3,3-trifluoropropene.
[0011] The invention also provides a method of forming an
azeotropic or azeotrope-like composition which comprises forming a
blend which consists essentially of from about 71.8 mole percent to
about 90.7 mole percent hydrogen fluoride and from about 9.3 mole
percent to about 28.2 mole percent
2-chloro-3,3,3-trifluoropropene.
[0012] The invention further provides a method for removing
2-chloro-3,3,3-trifluoropropene from a mixture containing
2-chloro-3,3,3-trifluoropropene and at least one impurity, which
comprises adding hydrogen fluoride to the mixture in an amount
sufficient to form an azeotropic or azeotrope-like composition
which consists essentially of from about 6.2 mole percent to about
59.9 mole percent hydrogen fluoride and from about 40.1 mole
percent to about 93.8 mole percent 2-chloro-3,3,3-trifluoropropene,
and thereafter separating the azeotropic composition from the
impurity.
[0013] The invention still further provides a method for removing
2-chloro-3,3,3-trifluoropropene from a mixture containing
2-chloro-3,3,3-trifluoropropene and at least one impurity, which
comprises adding hydrogen fluoride to the mixture in an amount
sufficient to form an azeotropic or azeotrope-like composition
which consists essentially of from about 71.8 mole percent to about
90.7 mole percent hydrogen fluoride and from about 9.3 mole percent
to about 28.2 mole percent 2-chloro-3,3,3-trifluoropropene, and
thereafter separating the azeotropic composition from the
impurity.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1 shows a plot of the vapor pressures of the mixtures
formed in Example 2 as measured at 0.degree. C., 25.degree. C. and
61.degree. C.
DETAILED DESCRIPTION OF THE INVENTION
[0015] In a method of preparing an HCFO-1233xf precursor, reagents
are fluorinated with hydrogen fluoride. This may be done, for
example, by the gas phase catalytic fluorination of
CCl.sub.2.dbd.CClCH.sub.2Cl with HF to yield HCFO-1233xf. Such
methods are disclosed in U.S. Application 20070197842, the
specification of which is incorporated herein by reference. The
reaction products of such precursors include HCFO-1233xf, unreacted
HF and other by-products. Upon removal of the by-products, a binary
azeotrope or azeotrope-like composition of HCFO-1233xf and HF is
formed. This binary azeotrope or azeotrope-like composition is then
available for separation into its component parts. The azeotropic
or azeotrope-like compositions of the HCFO-1233xf and HF are also
useful as recycle to the fluorination reactor. Thus, for example,
in a process for producing HCFO-1233xf, one can recover a portion
of the HCFO-1233xf as an azeotropic or azeotrope-like composition
of HCFO-1233xf and HF and then recycle the composition to the
reactor.
[0016] HCFO-1233xf forms azeotropic and azeotrope-like mixtures
with HF. The thermodynamic state of a fluid is defined by its
pressure, temperature, liquid composition and vapor composition.
For a true azeotropic composition, the liquid composition and vapor
phase are essentially equal at a given temperature and pressure
range. In practical terms this means that the components cannot be
separated during a phase change. For the purpose of this invention,
an azeotrope is a liquid mixture that exhibits a maximum or minimum
boiling point relative to the boiling points of surrounding mixture
compositions. An azeotrope or an azeotrope-like composition is an
admixture of two or more different components which, when in liquid
form under given pressure, will boil at a substantially constant
temperature, which temperature may be higher or lower than the
boiling temperatures of the components and which will provide a
vapor composition essentially identical to the liquid composition
undergoing boiling. For the purpose of this invention, azeotropic
compositions are defined to include azeotrope-like compositions
which means a composition that behaves like an azeotrope, i.e., has
constant-boiling characteristics or a tendency not to fractionate
upon boiling or evaporation. Thus, the composition of the vapor
formed during boiling or evaporation is the same as or
substantially the same as the original liquid composition. Hence,
during boiling or evaporation, the liquid composition, if it
changes at all, changes only to a minimal or negligible extent.
This is in contrast with non-azeotrope-like compositions in which
during boiling or evaporation, the liquid composition changes to a
substantial degree. Accordingly, the essential features of an
azeotrope or an azeotrope-like composition are that at a given
pressure, the boiling point of the liquid composition is fixed and
that the composition of the vapor above the boiling composition is
essentially that of the boiling liquid composition, i.e.,
essentially no fractionation of the components of the liquid
composition takes place. Both the boiling point and the weight
percentages of each component of the azeotropic composition may
change when the azeotrope or azeotrope-like liquid composition is
subjected to boiling at different pressures. Thus, an azeotrope or
an azeotrope-like composition may be defined in terms of the
relationship that exists between its components or in terms of the
compositional ranges of the components or in terms of exact weight
percentages of each component of the composition characterized by a
fixed boiling point at a specified pressure.
[0017] The present invention provides a composition which comprises
effective amounts of hydrogen fluoride and HCFO-1233xf to form an
azeotropic or azeotrope-like composition. By effective amount is
meant an amount of each component which, when combined with the
other component, results in the formation of an azeotrope or
azeotrope-like mixture. The inventive compositions preferably are
binary azeotropes which consist essentially of combinations of only
hydrogen fluoride with HCFO-1233xf.
[0018] In one embodiment, the inventive composition contains from
about 6.2 mole percent to about 59.9 mole percent HF, preferably
from about 53.5 mole percent to about 59.9 mole percent.
[0019] In another embodiment, the inventive composition contains
from about 71.8 mole percent to about 90.7 mole percent HF,
preferably from about 71.8 mole percent to about 86.7 mole percent
HF and most preferably from about 71.8 mole percent to about 85.3
mole percent based on the weight of the azeotropic or
azeotrope-like composition.
[0020] In one embodiment, the inventive composition contains from
about 40.1 mole percent to about 93.8 mole percent HCFO-1233xf,
preferably from about 40.1 mole percent to about 46.5 mole percent
based on the weight of the azeotropic or azeotrope-like
composition.
[0021] In another embodiment, the inventive composition contains
from about 9.3 mole percent to about 28.2 mole percent HCFO-1233xf,
preferably from about 13.3 mole percent to about 28.2 mole percent
and most preferably from about 14.7 mole percent to about 28.2 mole
percent based on the weight of the azeotropic or azeotrope-like
composition.
[0022] The composition of the present invention preferably has a
boiling point of about from 0.degree. C. to about 61.degree. C. at
a pressure of about 15 psia to about 107 psia. In one embodiment it
has a boiling point of about 0.degree. C. at a pressure of about 15
psia. In another embodiment it has a boiling point of about
25.degree. C. at a pressure of about 38 psia. In another embodiment
it has a boiling point of about 61.degree. C. at a pressure of
about 107 psia. An azeotropic or azeotrope-like composition having
about 82.5.+-.1.2 mole percent HF and about 17.5.+-.1.2 mole
percent HCFO-1233xf was found at 25.degree. C.
[0023] In another embodiment of the invention,
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) may be removed from a
mixture containing 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf)
and an impurity which may, for example, result from manufacturing
steps in the preparation of 2-chloro-3,3,3-trifluoropropene
(HCFO-1233xf). This is done by adding hydrogen fluoride to the
mixture of the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and
impurity. Hydrogen fluoride is added to the mixture in an amount
sufficient to form an azeotropic composition of the
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and the hydrogen
fluoride, and thereafter the azeotropic composition is separated
from the impurity, for example by distillation or other art
recognized separating means. In one embodiment, the impurity itself
does not form an azeotropic mixture with
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), hydrogen fluoride or
a mixture of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and
hydrogen fluoride. In another embodiment, the impurity does form an
azeotropic mixture with 2-chloro-3,3,3-trifluoropropene
(HCFO-1233xf), hydrogen fluoride or a mixture of
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and hydrogen
fluoride. Typical impurities of 2-chloro-3,3,3-trifluoropropene
(HCFO-1233xf) include other halocarbons which may be miscible with
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) such as
1,1,1,2,3-pentachloropropane; 1,1,2,3-tetrachloropropene;
2,3,3,3-tetrafluoropropene; 2,3-dichloro-3,3-difluoropropene
(HCFO-1232xf); 1,1,1,2,2-pentafluoropropane; or
1,2-dichloro-3,3,3-trifluoropropene.
[0024] The following non-limiting examples serve to illustrate the
invention.
Example 1
[0025] 60 g of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) were
mixed with 40 g of HF to form a heterogeneous azeotrope mixture.
The vapor pressure of the mixture at about 25.degree. C. was about
38 psia.
Example 2
[0026] Binary compositions containing solely
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and HF were blended
to form a heterogeneous azeotrope mixtures at different
compositions. The vapor pressures of the mixtures were measured at
about 0, 25 and 61.degree. C. and the following results were
noticed. Table 1 shows the vapor pressure measurements of
HCFO-1233xf and HF as a function of composition with varying weight
percent HF at constant temperatures of about 0, 25, and 61.degree.
C. The data also showed that HCFO-1233xf/HF is a heterogeneous
mixture.
TABLE-US-00001 TABLE 1 P-T-X of HCFO-1233xf/HF Pressure (Psia) Mole
% HF T = 0.degree. C. T = 25.degree. C. T = 61.degree. C. 0.00 8.87
22.88 64.58 12.70 14.21 35.2 85.62 22.50 14.69 38.48 102.4 38.34
15.03 38.4 106.08 46.46 15.03 38.35 107.34 55.06 15.03 38.45 106.95
67.39 15.03 38.45 106.95 76.06 15.03 38.45 107 81.72 15.03 38.45
107.05 86.27 15.08 38.4 102.88 98.36 12.51 29.04 72.53 99.30 9.7
23.17 61.72 100.00 6.87 17.82 52.43
[0027] The data also shows that the mixture is azeotropic or
azeotrope-like since the vapor pressure of the mixtures of
HCFO-1233xf and HF is higher, at all indicated blend proportions,
than vapor pressures of HCFO-1233xf and HF alone, i.e. as indicated
in the first and last rows of Table 1 when HF is 0.0 mole % and
HCFO-1233xf is at 100.0 mole % as well as when HCFO-1233xf is at
0.0 mole % and HF is at 100.0 mole %. The data from Table 1 is
shown in graphic form in FIG. 1.
Example 3
[0028] The azeotropic or azeotrope-like composition of the
HCFO-1233xf/HF mixture was also verified by Vapor-Liquid-Liquid
equilibrium (VLLE) experiment. 63.5 g of
2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) were mixed with 36.5
g of HF to form a heterogeneous mixture (visual observation) at
24.degree. C. The vapor composition, upper liquid (HF rich), and
bottom liquid (organic) were sampled. The result shows that the
azeotropic composition is about 82.5.+-.1.2 mole percent HF at
24.degree. C.
[0029] While the present invention has been particularly shown and
described with reference to preferred embodiments, it will be
readily appreciated by those of ordinary skill in the art that
various changes and modifications may be made without departing
from the spirit and scope of the invention. It is intended that the
claims be interpreted to cover the disclosed embodiment, those
alternatives which have been discussed above, and all equivalents
thereto.
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