The present invention relates, in part, to the discovery that, during the fluorination of certain fluoroolefin starting reagents, oligomerization/polymerization of such reagents reduces the conversion process and leads to increased catalyst deactivation. The present invention also illustrates that vaporizing such starting reagents in the presence of one or more organic co-feed reduces such oligomerization/polymerization and improves catalytic stability.

This invention provides a method for producing 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, in two or three reaction steps, using at least one chlorine-containing compound selected from the group consisting of 1,1,1,2,3-pentachloropropane, 2,3-dichloro-1,1,1-trifluoropropane, and 1,1,2,3-tetrachloropropene as a starting material, the reaction products of at least two of the steps being supplied to the same distillation apparatus to subject the products to a separation operation simultaneously. With this method, 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, can be efficiently produced with reduced energy and equipment costs in an economically advantageous manner.

A fluorination catalyst such as a chromium oxide-based fluorination catalyst may be activated or reactivated by contacting the catalyst. with a source of reactive fluorine, for example nitrogen trifluoride (NF3) or fluorine (F2). Fluorinated compounds may be prepared by the gas phase reaction of hydrogen fluoride (HF) with various substrates such as chlorinated compounds. A number of metal oxide-based catalysts have been developed for this purpose.

The present invention relates, in part, to the discovery that, during the fluorination of certain fluoroolefin starting reagents, oligomerization/polymerization of such reagents reduces the conversion process and leads to increased catalyst deactivation. The present invention also illustrates that vaporizing such starting reagents in the presence of one or more organic co-feed reduces such oligomerization/polymerization and improves catalytic stability.

This invention provides a method for producing 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, in two or three reaction steps, using at least one chlorine-containing compound selected from the group consisting of 1,1,1,2,3-pentachloropropane, 2,3-dichloro-1,1,1-trifluoropropane, and 1,1,2,3-tetrachloropropene as a starting material, the reaction products of at least two of the steps being supplied to the same distillation apparatus to subject the products to a separation operation simultaneously. With this method, 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, can be efficiently produced with reduced energy and equipment costs in an economically advantageous manner.

This invention provides a method for producing 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, in two or three reaction steps, using at least one chlorine-containing compound selected from the group consisting of 1,1,1,2,3-pentachloropropane, 2,3-dichloro-1,1,1-trifluoropropane, and 1,1,2,3-tetrachloropropene as a starting material, the reaction products of at least two of the steps being supplied to the same distillation apparatus to subject the products to a separation operation simultaneously. With this method, 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, can be efficiently produced with reduced energy and equipment costs in an economically advantageous manner.

This invention provides a method for producing 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, in two or three reaction steps, using at least one chlorine-containing compound selected from the group consisting of 1,1,1,2,3-pentachloropropane, 2,3-dichloro-1,1,1-trifluoropropane, and 1,1,2,3-tetrachloropropene as a starting material, the reaction products of at least two of the steps being supplied to the same distillation apparatus to subject the products to a separation operation simultaneously. With this method, 2,3,3,3-tetrafluoropropene or 2-chloro-1,1,1,2-tetrafluoropropane, which is a precursor of 2,3,3,3-tetrafluoropropene, can be efficiently produced with reduced energy and equipment costs in an economically advantageous manner.

The present invention relates to a process for the purification of a fluorocarbon from a mixture comprising said fluorocarbon and hydrogen, said process comprising a stage of bringing said mixture into contact with a membrane M1 to form a stream F1 comprising the fluorocarbon and a stream F2 comprising the hydrogen. The present invention also relates to a process for the production of trifluoroethylene. The present invention also relates to a process for the separation of a hydrofluoroolefin or of a hydrofluoroalkane from nitrogen by membrane separation. The present invention also relates to a process for the separation of trifluoroethylene from chlorotrifluoroethylene or from a hydrofluorocarbon.

In a first step reaction for producing 1,1,2-trifluoroethane (HFC-143) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) as part of an overall method for production of trans-1,2-difluoroethylene (HFO-1132E), several intermediates and/or byproducts are formed, some of which may be considered desired and others undesired. The overall reaction methods and/or specific reactions conditions for producing 1,1,2-trifluoroethane (HFC-143) from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) may be selectively tailored to usefully convert desired intermediates to the desired product 1,1,2-trifluoroethane (HFC-143) and/or minimize the formation of undesired byproducts.

A method for improving the stability of a catalyst in recycling HFC-23 is provided. The recycling is realized by means of a fluorine-chlorine exchange reaction with HFC-23 and a halogenated hydrocarbon. The catalyst for the fluorine-chlorine exchange reaction comprises a main body catalyst and a metal oxide, wherein the metal oxide is selected from at least one metal oxide of K, Na, Fe, Co, Cu, Ni, Zn or Ti, and has an addition amount of 0.1-5 wt %. The method has advantages such as a good catalyst stability, a long life, and a low content of by-product CFC-12.