AZEOTROPE OR AZEOTROPE-LIKE COMPOSITIONS OF 2-CHLORO-3,3,3-TRIFLUOROPROPENE (HCFO-1233XF) AND WATER
Heterogenous azeotrope or azeotrope-like compositions comprising 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and water which may include from about 0.09 wt. % to about 92.69 wt. % 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and from about 7.31 wt. % to about 99.91 wt. % water and having a boiling point between about 12.0° C. and about 13.6° C. at a pressure of between about 12.5 psia and about 16.5 psia. The azeotrope or azeotrope-like compositions may be used to separate impurities, including water, from 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf).
1 . A composition comprising an azeotrope or azeotrope-like composition consisting essentially of effective amounts of 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and water.
2 . The composition of claim 1 , wherein the azeotrope or azeotrope-like composition has a boiling point between about ¬¬¬¬12.0° C. and ¬about 13.6° C., preferably about 13.1 to about 13.2, at a pressure of between about 12.5 psia and about 16.5 psia, preferably about 14.5 psia.
3 . The composition of claim 1 , wherein the azeotrope or azeotrope-like composition consists essentially of from about 0.09 wt. % to about 92.69 wt. % 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and from about 7.31 wt. % to about 99.91 wt. % water;
preferably wherein the azeotrope or azeotrope-like composition consists essentially of from about 65 wt. % to about 90 wt. % 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and from about 10 wt. % to about 35 wt. % water;
preferably the azeotrope or azeotrope-like composition consists essentially of from about 65.14 wt. % to about 86.25 wt. % 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and from about 13.75 wt. % to about 34.86 wt. % water.
4 . A method of forming an azeotrope or azeotrope-like composition comprising the step of combining 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and water to form an azeotrope or azeotrope-like composition as defined in claim 1 .
5 . A method of separating impurities, including water, from 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) from a composition which 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and at least one impurity, comprising the steps of:
providing a composition including 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf) and at least one impurity;
modifying the relative amounts of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and water and subjecting the composition to conditions effective to form an azeotrope or azeotrope-like composition as defined in claim 1 ; and
separating the azeotrope or azeotrope-like composition from the 2-chloro-3,3,3-trifluoropropene (HFCO-1233xf).
6 . The method of claim 5 , wherein the separation step comprises at least one of phase separation, distillation, and fractionation; and/or
further comprising separating 2-chloro-3,3,3-trifluoropropene from the water, using a liquid-liquid phase separation, distillation or at least one drying agent.
7 . The method of claim 5 , wherein water is removed first by liquid-liquid phase separation, then by a second method selected from the group consisting of distillation, one or more drying agent, and combinations thereof.
8 . The method of claim 6 , wherein the step of modifying the relative amounts of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and water comprises:
adding 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) to the composition;
adding water to the composition; or
adding both 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and water to the composition.
9 . A method of producing 2,3,3,3-tetrafluoropropene (HFO-1234yf) comprising:
converting at least some of the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) present in the azeotrope or azeotrope-like composition defined in claim 1 into 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb); and
converting at least some of the 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) into 2,3,3,3-tetrafluoropropene (HFO-1234yf).
10 . The method of claim 9 , wherein the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) is separated from the water before being converted into 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb).
11 . The method of claim 9 , wherein converting at least some of the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) into 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) comprises reacting the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) with HF, preferably anhydrous HF, in the presence of a catalyst.
12 . The method of claim 11 , wherein:
the catalyst comprises metal halide catalyst, preferably selected from SbCl5, SbF5, TiCl4 or a combination thereof, or is a fluorosulfonic acid; and/or
converting at least some of the 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) into 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) is carried out at a temperature of 5-100° C., preferably 50-100° C.
13 . The method of claim 9 , wherein converting at least some of the 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) into 2,3,3,3-tetrafluoropropene (HFO-1234yf) comprises reacting the 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) with a base;
preferably in an aqueous environment, preferably in the presence of a phase transfer catalyst, preferably an ammonium halide, preferably a trialkylammonium halide of a tetraalkylammonium halide, preferably a trialkylammonium chloride of a tetraalkylammonium chloride; and/or
preferably the base is a caustic base, preferably an alkali metal hydroxide, preferably KOH or NaOH; and/or
preferably at a temperature of from about 0° C. to about 100° C., preferably from about 20° C. to about 90° C., preferably from about 50° C. to about 90° C., preferably from about 60° C. to about 80° C.