Process for the manufacture of 1-chloro-1,1-difluoroethane

Claim 2

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, comprising maintaining in the liquid medium a content of at least 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 30 mol % of vinylidene chloride and no more than 30 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio of between 1.5 and 3.7 by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium.

Claim 3

Process according to claim 1, wherein the liquid medium contains at least 60 mol % of 1,1-dichloro-1-fluoroethane relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium.

Claim 4

Process according to claim 1, wherein the catalyst is tin tetrachloride.

Claim 5

Process according to claim 1, wherein from 0.001 to 5 moles of catalyst are used per kg of liquid medium.

Claim 6

Process according to claim 2, wherein from 0.01 to 2 moles of catalyst are used per kg of liquid medium.

Claim 7

Process according to claim 1, wherein the reaction as carried out at a temperature of between 30° and 180° C.

Claim 8

Process according to claim 6, wherein the reaction is carried out at a temperature of between 40° and 160° C.

Claim 9

Process according to claim 1, wherein the reaction is carried out at a pressure of between 2 and 80 kg/cm 2 .

Claim 10

Process according to claim 8, wherein the reaction is carried out at a pressure of between 3 and 30 kg/cm 2 .

Claim 11

Process according to claim 1, wherein 1-chloro-1,1-difluoroethane is withdrawn in a gaseous phase.

Claim 12

Process according to claim 1, wherein at least a part of the 1-chloro-1,1-difluoroethane is withdrawn in a liquid phase.

Claim 13

Process according to claim 1, wherein the molar ratio of hydrogen fluoride to vinylidene chloride is between 1.75 and 3.7.

Claim 14

Process according to claim 1, wherein the liquid medium has a content of from 76.01 to 84.2 mol % of 1,1-dichloro-1-fluoroethane relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium and the molar ratio of hydrogen fluoride to vinylidene chloride is 2.8 to 2.9.

Claim 15

Process according to claim 1, wherein the gaseous phase containing 1-chloro-1,1-difluoroethane is separated into its components, 1,1-dichloro-1-fluoroethane is collected, and the collected 1,1-dichloro-1-fluoroethane is recycled to the liquid reaction medium.

Claim 16

Process according to claim 11, wherein the phase containing 1-chloro-1,1-difluoroethane is separated into its components, 1,1-dichloro-1-fluoroethane is collected, and the collected 1,1-dichloro-1-fluoroethane is recycled to the liquid reaction medium.

Claim 17

Process according to claim 1, wherein the 1-chloro-1,1-difluoroethane is continuously withdrawn as both liquid and gaseous phases from the liquid medium.

Claim 18

Process according to claim 16, wherein both said liquid and gaseous phases are subjected to a separation to collect 1,1-dichloro-1-fluoroethane and the collected 1,1-dichloro-1-fluoroethane is recycled to the liquid reaction medium.

Claim 19

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.9 by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane while forming very little 1,1,1-trifluoroethane.

Claim 20

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.9 by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane while forming very little 1,1,1-trifluoroethane.

Claim 21

Process according to claim 18, said process further defining a molar ratio of 1,1,1-trifluoroethane: 1-chloro-1,1-difluoroethane is less than 0.080.

Claim 22

Process according to claim 15, wherein said molar ratio of 1,1,1-trifluoroethane: 1-chloro-1,1-difluoroethane is less than 0.029.

Claim 23

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.7, by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane while substantially reducing the formation of oligomers.

Claim 24

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.7, by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane while substantially reducing the formation of oligomers.

Claim 25

The process of claim 21, wherein the degree of conversion of vinylidene chloride to oligomers is 1.4 mol %.

Claim 26

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.7, by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane.

Claim 27

Continuous process for the manufacture of 1-chloro-1,1-difluoroethane by reacting hydrogen fluoride with vinylidene chloride, wherein the reaction is carried out in a liquid medium in the presence of a hydrofluorination catalyst which is a tin compound, said reaction forming 1-chloro-1,1-difluoroethane,1,1-dichloro-1-fluoroethane,1,1,1-trifluoroethane and oligomers, comprising maintaining in the liquid medium a content greater than 40 mol % of 1,1-dichloro-1-fluoroethane, no more than 50 mol % of vinylidene chloride and no more than 50 mol % of 1-chloro-1,1-difluoroethane, all relative to the total number of moles of organic compounds participating in the reaction and present in the liquid medium, while feeding into the liquid medium hydrogen fluoride and vinylidene chloride in a hydrogen fluoride/vinylidene chloride molar ratio between 1.5 and 3.7, by continuously withdrawing 1-chloro-1,1-difluoroethane from the liquid medium, said withdrawing process step defining very high yields of 1-chloro-1,1-difluoroethane.

Claim 28

The process of claim 19, wherein said withdrawing process having a product yield of at least 80.5 mol % of 1-chloro-1,1-difluoroethane.

Claim 29

The process of claim 19, wherein said withdrawing process step substantially reduces the formation of 1,1,1-trifluoroethane and oligomers.

Claim 30

The process of claim 21, wherein the degree of vinylidene chloride conversion to the combination of 1,1,1-trifluoroethane and oligomers is equal to or less than 2.7 mol %.

Claim 31

The process of claim 20, wherein said liquid medium has a 60 mol % of 1,1-dichloro-1-fluoroethane, no more 30 mol % of vinylidene chloride and no more than 30 mol % of 1-chloro-1,1-difluoroethane.