# Patent

## Title
Composition including 2,3,3,3-tetrafluoropropene

## Abstract

A composition including the compound HFO-1234yf and at least one other, additional, compound selected from HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCC-40, HCFC-114a, HCFC-115, HCFC-122, HCFC-23, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HFC-52a, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd, and HCFO-1224xe. A composition including the compound HFO-1234yf and at least two compounds selected from HFO-1234ze, HFC-245cb, HFC-134a, HCFC-115, HFC-152a, HCC-40 and HFO-1243zf.

## Background
The present invention relates to compositions comprising 2,3,3,3-tetrafluoropropene, which are of use in many fields of application such as refrigeration, blowing agents, solvents and aerosols.
One very important parameter in the choice of a composition of use in the fields of refrigeration, air conditioning and heat pumps is its impact on the environment.
The manufacture of 2,3,3,3-tetrafluoropropene (HFO-1234yf), being accompanied by a multitude of by-products having a boiling point close to HFO-1234yf, results in quite complex and expensive purification steps. The difficulty encountered during the purification of HFO-1234yf generally involves a consequent loss of desired product. Furthermore, these by-products may form binary or tertiary azeotropic compositions with HFO-1234yf, rendering the separation by simple distillation impossible.
One subject of the present invention is a composition comprising the compound HFO-1234yf and at least one other additional compound chosen from HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCC-40, HCFC-114a, HCFC-115, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HFC-152a, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd and HCFO-1224xe.
Preferably, all of the additional compounds represents at most 1% by weight of the composition comprising the HFO-1234yf and advantageously at most 0.5% by weight.
Compounds such as HCFC-115, HFC-152a and HCC-40 have a boiling point particularly close to that of HFO-1234yf.
According to one embodiment of the invention, the composition comprises the compound HFO-1234yf and at least one other additional compound chosen from HCFC-115, HFC-152a and HCC-40, preferably HFC-152a and/or HCC-40.
Advantageously, the HCFC-115 and/or HFC-152a and/or HCC-40 when it (they) is (are) present in the composition, represent(s) at most 500 ppm and particularly preferably represent(s) at most 50 ppm.
According to this embodiment, the composition may additionally comprise at least one compound chosen from HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCFC-114a, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd and HCFO-1224xe.
In one embodiment, the composition according to the invention may also comprise at least one compound chosen from HFO-1234ze, HFC-245cb, HFC-245eb, HFC-245fa, HFC-23, HFC-134a, HFC-143a, HFC-236fa, HCFC-244bb, HCFC-244db, HFO-1132a, HFO-1223, HFO-1225zc, HFO-1225ye, HCFO-1232xf and HFO-1243zf.
Irrespective of the embodiment, all of the additional compound(s) represents at most 1% by weight of the composition comprising the HFO-1234yf and advantageously at most 0.5% by weight.
By way of example, mention may especially be made of the following compounds, the acronyms of which represent:

    
    
        HCFC-240db: 1,1,1,2,3-pentachloropropane or CCl3—CHCl—CH2Cl
        HCFO-1233xf: 3,3,3-trifluoro-2-chloropropene or CF3—CCl═CH2 
        HCFC-243db: 1,1,1-trifluoro-2,3-dichloropropane or CF3—CHCl—CH2Cl
        HCFO-1233zd: E/Z-3,3,3-trifluoro-1-chloropropene or CF3—CH═CHCl
        HCC-40: chloromethane or CH3Cl
        HCFC-114a: 1,1,1,2-tetrafluoro-2,2-dichloroethane or CF3—CCl2F
        HCFC-115: 1,1,1,2,2-pentafluoro-2-chloroethane CF3—CClF2 
        HCFC-122: 1,1,2-trichloro-2,2-difluoroethane or CHCl2—CClF2 
        HCFC-123: 1,1,1-trifluoro-2,2-dichloroethane or CF3—CHCl2 
        HCFC-124: 1,1,1,2-tetrafluoro-2-chloroethane or CF3—CHClF
        HCFC-124a: 1,1,2,2,-tetrafluoro-2-chloroethane or CHF2—CClF2 
        HFC-125: 1,1,1,2,2,-pentafluoroethane or CF3—CHF2 
        HCFC-133a: 1,1,1-trifluoro-2-chloroethane or CF3—CH2Cl
        HCFC-142: 1,1-difluoro-2-chloroethane or CHF2—CH2Cl
        HCFC-143: 1,1,2-trifluoroethane or CHF2—CH2F
        HFC-152a: 1,1-difluoroethane or CHF2—CH3 
        HCFC-243ab: 1,1,1-trifluoro-2,2-dichloropropane or CF3—CCl2—CH3 
        HCFC-244eb: 1,1,1,2-tetrafluoro-3-chloropropane or CF3—CHF—CH2Cl
        HFC-281ea: 2-fluoropropane or CH3—CFH—CH3 
        HCO-1110: 1,1,2,2-tetrachloroethylene or CCl2═CCl2 
        HCFO-1111: 1,1,2-trichloro-2-fluoroethylene or CCl2═CClF
        HCFO-1113: 1,1,2-trifluoro-2-chloroethylene or CF2═CClF
        HCFO-1223xd: E/Z-3,3,3-trifluoro-1,2-dichloropropene or CF3—CCl═CHCl
        HCFO-1224xe: E/Z-1,3,3,3-tetrafluoro-2-chloropropene or CF3—CCl═CHF
        HFO-1234ze: E/Z-1,3,3,3-tetrafluoropropene or CF3—CH═CHF
        HFC-245cb: 1,1,1,2,2-pentafluoropropane or CF3—CF2—CH3 
        HFC-245eb: 1,1,1,2,3-pentafluoropropane or CF3—CHF—CH2F
        HFC-245fa: 1,1,1,3,3-pentafluoropropane or CF3—CH2—CHF2 
        HFC-23: trifluoromethane or CHF3 
        HFC-134a: 1,1,1,2-tetrafluoroethane or CF3—CH2F
        HFC-143a: 1,1,1-trifluoroethane or CF3—CH3 
        HFC-236fa: 1,1,1,3,3,3-hexafluoropropane or CF3—CH2—CF3 
        HCFC-244bb: 1,1,1,2-tetrafluoro-2-chloropropane or CF3—CFCl—CH3 
        HCFC-244db: 1,1,1,3-tetrafluoro-2-chloropropane or CF3—CHCl—CH2F
        HFO-1132a: 1,2-difluoroethylene or CHF═CHF
        HFO-1223: 3,3,3-trifluoropropyne or CF3—C≡CH
        HFO-1225zc: E/Z-1,1,3,3,3-pentafluoropropene or CF3—CH═CF2 
        HFO-1225ye: E/Z-1,2,3,3,3-pentafluoropropene or CF3—CF═CHF
        HCFO-1232xf: 3,3-difluoro-1,3-dichloropropene or CClF2—CCl═CH2 
        HFO-1243zf: 3,3,3-trifluoropropene or CF3—CH═CH2 
    
    


According to one more particular embodiment, the composition according to the invention may comprise a ternary mixture, for example a mixture chosen from:

    
    
        HFO-1234yf, HFC-152a, HFC-245cb
        HFO-1234yf, HCC-40, HFC-245cb
        HFO-1234yf, HCFC-115, HFC-245cb
        HFO-1234yf, HFC-152a, HFC-134a
        HFO-1234yf, HCC-40, HFC-134a
        HFO-1234yf, HCFC-115, HFC-134a
        HFO-1234yf, HFC-152a, HFO-1234ze
        HFO-1234yf, HCC-40, HFO-1234ze
        HFO-1234yf, HCFC-115, HFO-1234ze
        HFO-1234yf, HCC-40, HFC-152a
        HFO-1234yf, HCC-40, HCFC-115
        HFO-1234yf, HFC-134a, HFO-1234ze
        HFO-1234yf, HFC-134a, HFO-1243zf
        HFO-1234yf, HFO-1234ze, HFC-134a
        HFO-1234yf, HFO-1234ze, HFC-245cb
        HFO-1234yf, HFO-1243zf, HFC-245cb
        HFO-1234yf, HFO-1243zf, HFC-152a
        HFO-1234yf, HFO-1243zf, HCFC-115
    
    


According to one more particular embodiment, the composition according to the invention may comprise a quaternary mixture, for example a mixture chosen from:

    
    
        HFO-1234yf, HFC-152a, HCC-40, HFC-245cb
        HFO-1234yf, HFC-152a, HCC-40, HFC-1234ze
    
    


It would not be outside the scope of the invention if the composition comprises a mixture of more than four compounds.
Another subject of the present invention is a composition comprising the compound HFO-1234yf and at least two compounds chosen from HFO-1234ze, HFC-245cb, HFC-134a, HCFC-115, HFC-152a, HCC-40 and HFO-1243zf.
Preferably, the composition comprises the compound HFO-1234yf, HCC-40 and at least one compound chosen from HFO-1234ze, HFC-134a, HCFC-115, HFC-152a and HFO-1243zf.
Preferably, the composition comprises the compound HFO-1234yf, HFC-134a and at least one compound chosen from HFO-1234ze, HCFC-115, HFC-152a and HFO-1243zf.
Preferably, the composition comprises the compound HFO-1234yf, HFO-1234ze and at least one compound chosen from HFC-245cb, HCFC-115, HFC-152a and HFO-1243zf.
Preferably, the composition comprises the compound HFO-1234yf, HFO-1243zf and at least one compound chosen from HFC-245cb, HCFC-115 and HFC-152a.
The preferred and/or aforementioned compositions may additionally comprise at least one other additional compound chosen from HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCFC-114a, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd, HFC-245eb, HFC-245fa, HFC-23, HFC-143a, HFC-236fa, HCFC-244bb, HCFC-244db, HFO-1132a, HFO-1223, HFO-1225zc, HFO-1225ye, HCFO-1232xf and HCFO-1224xe.
Irrespective of the embodiment, the compound HFO-1234yf preferably represents at least 99% by weight in the composition and advantageously at least 99.5% by weight.
The composition according to the invention may be obtained from HCC-240db and by using one or more reaction steps.
Thus, HCC-240db may be subjected to a gas-phase reaction step with a fluorinating agent, preferably anhydrous HF, in order to directly give HFO-1234yf, optionally accompanied by intermediate products chosen from HCFO-1233xf, HCFC-243db and HCFO-1233zd. The fluorination reaction may be carried out in the presence of a catalyst and preferably at a temperature between 100° C. and 500° C., more preferably between 200° C. and 450° C. After separation of the HFO-1234yf, in particular by settling followed by distillation, the intermediate product(s) and where appropriate the unreacted HCC-240db may then be recycled to the reaction step.
The composition according to the invention may also be obtained from HCC-240db by means of at least two reaction steps. The first step generally consists in subjecting the HCC-240db to a gas-phase reaction with a fluorinating agent, preferably anhydrous HF, in order to give at least one intermediate product such as HCFO-1233xf. In a second step, the intermediate product reacts with a fluorinating agent, preferably anhydrous HF, in order to give a composition comprising HFO-1234yf and at least one additional compound as described above. At the end of the second step, the composition comprising the HFO-1234yf and at least one additional compound is subjected to a separation and/or purification step.
The two steps may be carried out in the presence of a catalyst, it being possible for the catalyst to be identical or different. These steps may be carried out in one and the same reactor when the reaction is carried out in the gas phase. In this case, the reactor may comprise an upper catalyst bed different from that of the lower bed.
When the preparation is carried out using two reactions steps, the reaction temperature of the first step is generally lower than that of the second step and is preferably between 100° C. and 500° C., more preferably between 200° C. and 450° C.
If necessary, after the aforementioned separation and/or purification step, the stream comprising HFO-1234yf may be subjected to a step of azeotropic distillation and/or of adsorption by activated carbon and/or molecular sieve or to a photochlorination step.
According to one embodiment of the invention, the composition is obtained by a series of reactions (FIG. 1). FIG. 1 illustrates a series of reactions for the production of HFO-1234yf. The series of reactions begins with a hydrofluorination reaction of HCC-240db with hydrogen fluoride to give HCFO-1233xf. The compound HCFO-1233xf may in turn undergo a hydrofluorination reaction to give HFO-1234yf. The compound HFO-1234yf may in turn undergo a hydrofluorination reaction to give HFC-245cb. Multitudes of products may be obtained by reactions parallel to this series of reactions for example by isomerization reactions, HCl addition reactions and chlorination reactions.


The reactions described above are preferably carried out in the presence of a supported or unsupported fluorination catalyst, preferably activated in the presence of hydrogen fluoride and/or air, comprising chromium oxides and optionally a co-catalyst based for example on nickel, zinc, titanium, magnesium and tin.
The hydrofluorination reaction(s) may be carried out in the gas phase, optionally in the presence of a sufficient amount of oxygen.
The production of HFO-1234yf may be carried out in one or more reactors in series. The supply of HCC-240db may be placed at the inlet of one of the reactors or at the inlet of the first reactor in series, or at each of the inlets of each of the reactors in series.
The hydrofluorination reaction(s) may be carried out continuously or semi-continuously.
The production of HFO-1234yf may be preferably carried out at an absolute pressure of between 0.1 and 50 bar, more preferably between 0.3 and 15 bar.
The contact time in the reactor is between 1 and 100 seconds, preferably between 5 and 50 seconds.
The molar ratio between the hydrogen fluoride and the organic compounds is between 4:1 and 100:1, preferably between 5:1 and 50:1.
The compositions described according to the invention may contain HF, HCl and inert gases (nitrogen, oxygen, carbon dioxide, carbon monoxide, etc).
HF and HCl neutralization/elimination steps may also be carried out. The compositions described according to the invention may also contain no, or contain traces of, HF and/or HCl.
In the presence of a large excess of HF used in the reaction step(s), the manufacture of HFO-1234yf may comprise at least one distillation step in order to recover a portion of HF that can be recycled to the reaction step(s).
The compositions according to the invention are of use in many fields of application, especially as heat transfer fluid, propellants, foaming agents, blowing agents, gaseous dielectrics, monomer or polymerization medium, support fluids, agents for abrasives, drying agents and fluids for energy production units.

## Claims

1. A composition comprising the compound HFO-1234yf and at least one other additional compound chosen from HCFC-240db, HCC-40, HCFC-114a, HCFC-115, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-142, HCFC-143, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, and HCFO-1224xe,
wherein the composition comprises at most 0.5% by weight of all of the additional compound(s), and
wherein the at least one other additional compound includes HCC-40.

2. The composition as claimed in claim 1, wherein the at least one other additional compound further includes HCFC-115.

3. The composition as claimed in claim 2, wherein the composition further comprises at least one compound chosen from HFC-152a, HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCFC-114a, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd and HCFO-1224xe.

4. The composition as claimed in claim 1, wherein the composition further comprises at least one compound chosen from HFO-1234ze, HFC-245cb, HFC-245eb, HFC-245fa, HFC-23, HFC-134a, HFC-143a, HFC-236fa, HCFC-244bb, HCFC-244db, HFO-1132a, HFO-1223, HFO-1225zc, HFO-1225ye, HCFO-1232xf and HFO-1243zf.

5. A composition according to claim 1 comprising at least 99% by weight of HFO-1234yf and up to 500 ppm of HCC-40.

6. The composition as claimed in claim 5, wherein the composition comprises up to 50 ppm of HCC-40.

7. The composition as claimed in claim 5, wherein the composition comprises at least 99.5% by weight of HFO-1234yf.

8. The composition as claimed in claim 1, wherein the composition comprises at least 99% by weight of HFO-1234yf.

9. The composition as claimed in claim 1, wherein the composition comprises at least 99.5% by weight of HFO-1234yf.

10. The composition as claimed in claim 1, wherein the composition comprises HFO-1234yf, HCC-40, and at least one compound selected from the group consisting of HFO-1234ze, HCFC-115, HFC-152a, and HFO-1243zf.

11. The composition as claimed in claim 1, wherein the composition further comprises at least one compound chosen from HFO-1234ze, HFC-245cb, HFC-134a, HCFC-115, HFC-152a, HCC-40 and HFO-1243zf.

12. The composition as claimed in claim 11, wherein the composition additionally comprises at least one other additional compound chosen from HCFC-240db, HCFO-1233xf, HCFC-243db, HCFO-1233zd, HCFC-114a, HCFC-122, HCFC-123, HCFC-124, HCFC-124a, HFC-125, HCFC-133a, HCFC-142, HCFC-143, HCFC-243ab, HCFC-244eb, HFC-281ea, HCO-1110, HCFO-1111, HCFO-1113, HCFO-1223xd, HFC-245eb, HFC-245fa, HFC-23, HFC-143a, HFC-236fa, HCFC-244bb, HCFC-244db, HFO-1132a, HFO-1223, HFO-1225zc, HFO-1225ye, HCFO-1232xf and HCFO-1224xe.

13. The composition as claimed in claim 1, wherein the composition further comprises at least one compound chosen from HFO-1234ze, HFC-134a, HCFC-115, HFC-152a and HFO-1243zf.