Disclosed is a method for co-producing various alkenyl halides and hydrofluoroalkanes: cis-1-chloro-3,3,3-trifluoropropene is introduced into a first reactor to carry out an isomerization reaction in the presence of a first catalyst, and the reaction product is rectified to obtain a product trans-1-chloro-3,3,3-trifluoropropene; and 30-70 wt % of trans-1-chloro-3,3,3-trifluoropropene and hydrogen fluoride are mixed and then introduced into a second reactor to carry out a reaction in the presence of a second catalyst to obtain a second reactor reaction product; the second reactor reaction product is introduced into a phase separator for separation, and the obtained organic phase is rectified to obtain the products trans-1,3,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene and 1,1,1,3,3-pentafluoropropane. The invention has the advantages of simple process, high efficiency, high operation flexibility, less investment and low energy consumption.

Disclosed is a method for co-producing various alkenyl halides and hydrofluoroalkanes: cis-1-chloro-3,3,3-trifluoropropene is introduced into a first reactor to carry out an isomerization reaction in the presence of a first catalyst, and the reaction product is rectified to obtain a product trans-1-chloro-3,3,3-trifluoropropene; and 30-70 wt % of trans-1-chloro-3,3,3-trifluoropropene and hydrogen fluoride are mixed and then introduced into a second reactor to carry out a reaction in the presence of a second catalyst to obtain a second reactor reaction product; the second reactor reaction product is introduced into a phase separator for separation, and the obtained organic phase is rectified to obtain the products trans-1,3,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene and 1,1,1,3,3-pentafluoropropane. The invention has the advantages of simple process, high efficiency, high operation flexibility, less investment and low energy consumption.

Disclosed is a method for co-producing various alkenyl halides and hydrofluoroalkanes: cis-1-chloro-3,3,3-trifluoropropene is introduced into a first reactor to carry out an isomerization reaction in the presence of a first catalyst, and the reaction product is rectified to obtain a product trans-1-chloro-3,3,3-trifluoropropene; and 30-70 wt % of trans-1-chloro-3,3,3-trifluoropropene and hydrogen fluoride are mixed and then introduced into a second reactor to carry out a reaction in the presence of a second catalyst to obtain a second reactor reaction product; the second reactor reaction product is introduced into a phase separator for separation, and the obtained organic phase is rectified to obtain the products trans-1,3,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene and 1,1,1,3,3-pentafluoropropane. The invention has the advantages of simple process, high efficiency, high operation flexibility, less investment and low energy consumption.

The objective of the present invention is to provide a refrigerant circulation device and a refrigerant circulation method with which a change in pressure inside the device can be avoided and performance stability and stable operation are achieved even when a HFO or a HCFO refrigerant is used. In the refrigerant circulation device (1), a refrigerant circulation circuit for circulating a refrigerant is formed by connecting a compressor (3), a condenser (5), an expansion valve (7), and an evaporator (9) through primary pipes (11a, 11b, 11c, 11d), and the refrigerant circulation circuit is charged with a refrigerant containing hydrofluoroolefin or hydrochlorofluoroolefin having a carbon-carbon double bond in the molecular structure. The refrigerant circulation device (1) is provided with a recovery catalyst that is arranged so as to be capable of contacting the refrigerant in the refrigerant circulation circuit, and is for returning, to the pre-isomerization state, an isomer formed by isomerization of the hydrofluoroolefin or hydrochlorofluoroolefin contained in the initial refrigerant with which the refrigerant circulation circuit is initially charged.

The objective of the present invention is to provide a refrigerant circulation device and a refrigerant circulation method with which a change in pressure inside the device can be avoided and performance stability and stable operation are achieved even when a HFO or a HCFO refrigerant is used. In the refrigerant circulation device (1), a refrigerant circulation circuit for circulating a refrigerant is formed by connecting a compressor (3), a condenser (5), an expansion valve (7), and an evaporator (9) through primary pipes (11a, 11b, 11c, 11d), and the refrigerant circulation circuit is charged with a refrigerant containing hydrofluoroolefin or hydrochlorofluoroolefin having a carbon-carbon double bond in the molecular structure. The refrigerant circulation device (1) is provided with a recovery catalyst that is arranged so as to be capable of contacting the refrigerant in the refrigerant circulation circuit, and is for returning, to the pre-isomerization state, an isomer formed by isomerization of the hydrofluoroolefin or hydrochlorofluoroolefin contained in the initial refrigerant with which the refrigerant circulation circuit is initially charged.

A method for isomerizing a hydrohalofluoroolefin isomer to produce a corresponding hydrohalofluoroolefin isomer includes a step contacting a composition that contains at least a hydrohalofluoroolefin isomer and that has been adjusted to 100 ppm or lower in moisture concentration, with a catalyst in a gas phase, thereby obtaining a product. This method makes it possible to suppress the catalyst performance lowering.

A method for isomerizing a hydrohalofluoroolefin isomer to produce a corresponding hydrohalofluoroolefin isomer includes a step contacting a composition that contains at least a hydrohalofluoroolefin isomer and that has been adjusted to 100 ppm or lower in moisture concentration, with a catalyst in a gas phase, thereby obtaining a product. This method makes it possible to suppress the catalyst performance lowering.

A method for isomerizing a hydrohalofluoroolefin isomer to produce a corresponding hydrohalofluoroolefin isomer includes a step contacting a composition that contains at least a hydrohalofluoroolefin isomer and that has been adjusted to 100 ppm or lower in moisture concentration, with a catalyst in a gas phase, thereby obtaining a product. This method makes it possible to suppress the catalyst performance lowering.

To provide a method and a composition for producing a geometric isomer (isomer 2) represented by a certain formula (1) by geometrically isomerizing a corresponding geometric isomer (isomer 1) represented by the certain formula (1), the method including, contacting the geometric isomer (isomer 1) represented by the certain formula (1) with a compound (A) which is at least one of a dichlorotrifluoropropane and hydrogen chloride in a gas phase.

To provide a method and a composition for producing a geometric isomer (isomer 2) represented by a certain formula (1) by geometrically isomerizing a corresponding geometric isomer (isomer 1) represented by the certain formula (1), the method including, contacting the geometric isomer (isomer 1) represented by the certain formula (1) with a compound (A) which is at least one of a dichlorotrifluoropropane and hydrogen chloride in a gas phase.