149 results about "HFO-1234yf" patented technology

The present invention relates to an improved method for manufacturing 2-chloro-3,3,3,-trifluoropropene (HCFC-1233xf) by reacting 1,1,2,3-tetrachloropropene, 1,1,1,2,3-pentachloropropane, and/or 2,3,3,3-tetrachloropropene with hydrogen fluoride, in a vapor phase reaction vessel in the presence of a vapor phase fluorination catalyst and stabilizer. HCFC-1233xf is an intermediate in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf) which is a refrigerant with low global warming potential.

The invention provides a method for separating halocarbons. In particular, a method for separating 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) from 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) based on differences in melting points of these compounds. More particularly the invention pertains to a method for separating HCFC-244bb from HCFO-1233xf which are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

Provided are azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb). Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

The invention discloses a refrigerant composition capable of replacing HFC-134a, consisting of 2,3,3,3-tetrafluoropropene (HFO-1234yf), trans-1,3,3,3-tetrafluoropropene (HFO-1234ze (E)) and 1,1-difluoroethane (HFC-152a). The ozone depleting potential (ODP) value of the refrigerant composition is zero and the value of global warm potential (GWP) is extraordinary low, thus conforming to the requirement of environmental protection, and the refrigerant composition of the invention has the physical property equivalent to the physical property of HFC-134a, can be directly used for the existing HFC-134a system without redesigning a compressor.

Provided are ternary azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), 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).

The present invention relates, in part, to the discovery that the presence of impurities in a reactor for dehydrochlorinating HCFC-244bb to HFO-1234yf results in selectivity changeover from HFO-1234yf to HCFO-1233xf. By substantially removing such impurities, it is shown that the selectivity to HFO-1234yf via dehydrochlorination of HCFC-244bb is improved.

This invention provides a method for purifying HFO-1234yf by removing HF from a mixture of HFO-1234yf and HF under simple and economically advantageous conditions. According to the present invention, this is a purification method for 2,3,3,3-tetrafluoropropene, (1) the purification method comprising the step of subjecting a mixture comprising 2,3,3,3-tetrafluoropropene and hydrogen fluoride to extractive distillation in a distillation column A using an extractant, thereby obtaining a fraction I that contains 2,3,3,3-tetrafluoropropene and has a lower ratio of hydrogen fluoride to 2,3,3,3-tetrafluoropropene than that of the mixture, while obtaining a fraction II that contains hydrogen fluoride and has a lower ratio of 2,3,3,3-tetrafluoropropene to hydrogen fluoride than that of the mixture; (2) the extractant comprising at least one member selected from the group consisting of: (i) alcohols represented by ROH, wherein R is a C_1-5 alkyl group, (ii) ethers represented by ROR′, wherein R and R′ are the same or different, and each is a C_1-4 alkyl group, (iii) fluorinated alcohols represented by RfOH, wherein Rf is a C_1-3 fluoroalkyl group, (iv) ketones represented by RCOR′, wherein R and R′ are the same or different, and each is a C_1-4 alkyl group, (v) esters represented by RCOOR′, wherein R and R′ are the same or different, and each is a C_1-4 alkyl group, (vi) polyols represented by R(OH)n, wherein R is a C_1-4 alkyl group, and n is an integer of 2 to 3, and (vii) ethylene glycols represented by R¹O(CH₂CH₂O)_nR², wherein R¹ and R² are the same or different, and each is hydrogen or a C_1-4 alkyl group, and n is an integer of 1 to 3.

A non-flammable refrigerant mixture is disclosed. The non-flammable refrigerant mixture may include from 20 weight percent to 25.5 weight percent HFO-1234yf, (b) from 20 weight percent to 24.5 weight percent HFC-32, (c) from 24.5 weight percent to 30 weight percent HFC-125, (d) from 25.5 weight percent to 30 weight percent HFC-134a, and optionally (e) from about 0.0001 weight percent to 10 weight percent trans-HFO-1234ze. These refrigerant mixtures are useful as components in compositions also containing non-refrigerant components (e.g., lubricants), in processes to produce cooling, in methods for replacing refrigerants R-404A, R-507, R-407A, R-407C, R-407F and/or R-22, and in refrigeration apparatuses.

The present invention provides a method for purifying HFO-1234yf, comprising the steps of (1) cooling a liquid mixture containing HFO-1234yf and HF to separate the mixture into a upper liquid phase having a high concentration of HF and a lower liquid phase having a high concentration of 2,3,3,3-tetrafluoropropene; and (2) subjecting the lower liquid phase obtained in step (1) to a distillation operation to withdraw a mixture containing HFO-1234yf and HF from a top of a distillation column, thereby obtaining substantially HF-free HFO-1234yf from a bottom of the distillation column. According to the present invention, HF and HFO-1234yf contained in a mixture containing HF and HFO-1234yf can be separated under simple and economically advantageous conditions.

The present invention pertains to ternary azeotrope and azeotrope-like composition including 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), HF, and either 1,1,2,3-tetrachloropropene (TCP) or 1,1,1,2,2-pentafluoropropane (HFC-245cb). The present invention also relates to binary azeotropes of 2,3,3,3-tetrachloropropene and HF. Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

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).

A method for producing a tetrafluoroolefin, such as 2,3,3,3-tetrafluoropropene (HFO-1234yf), comprises contacting 1,1,1,2-tetrachloro-2-fluoropropane (HCFC-241bb) with or without a catalyst under conditions effective to convert the 1,1,1,2-tetrachloro-2-fluoropropane (HCFC-241bb) to the tetrafluoroolefin, optionally, via an intermediate. The conversion may be a one-step fluorination or a two-step fluorination and dehydrochlorination process. The 1,1,1,2-tetrachloro-2-fluoropropane (HCFC-241bb) may also be obtained by dehydrochlorinating 1,2,3-trichloropropane (HCC-260da) to form 2,3-dichloropropene (HCO-1250xf); fluorinating 2,3-dichloropropene (HCO-1250xf) to form 1,2-dichloro-2-fluoropropane (HCFC-261bb); and chlorinating 1,2-dichloro-2-fluoropropane (HCFC-261bb) to form 1,1,1,2-tetrachloro-2-fluoropropane (HCFC-241bb).

The present invention relates, in part, to the discovery that the presence of moisture in 1,1,2,3-tetrachloropropene (HCO-1230xa) results in catalyst deactivation and accelerated corrosion in the reactor during the fluorination of HCO-1230xa to 2-chloro-3,3,3-trifluoropropene. By substantially removing the moisture, it is shown that the catalyst life is extended and results in improved operation efficiency of the fluorination reaction. Such steps similarly result in an overall improvement in the production of certain hydrofluoroolefins, particularly 2,3,3,3-tetrafluoropropene (HFO-1234yf).

Provided are azeotropic and azeotrope-like compositions of 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) 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).