Composition comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene
AssigneeArkema France
InventorsDominique GARRAIT, Camille SCHERPEREEL
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Abstract
Azeotropic and quasi-azeotropic compositions comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene. Also, a method for producing compositions comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene. The composition may include from 1 mol % to 99 mol % of 1-chloro-2,2-difluoroethane and from 99 mol % to 1 mol % of 1,1-dichloroethylene on the basis of the total composition thereof expressed in moles and the boiling point of the composition may be between 30° C. and 116° C.
Claims12
An azeotropic or quasi-azeotropic composition comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene.
A process for producing a composition comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene, comprising
- (i) at least one step during which the 1,1,2-trichloroethane reacts with hydrofluoric acid in the gas phase, optionally in the presence of an oxidizing agent, and in the presence or absence of a fluorination catalyst, to give a stream comprising 1-chloro-2,2-difluoroethane, hydrochloric acid, hydrofluoric acid and at least one compound A chosen from 1,2-dichloroethylenes (cis and trans), 1-chloro-2-fluoroethylenes (cis and trans), 1,2-dichloro-2-fluoroethane and unreacted 1,1,2-trichloroethane;
- (ii) at least one step of separating the compounds resulting from the reaction step, to give a first stream comprising hydrochloric acid and a second stream comprising hydrofluoric acid, 1-chloro-2,2-difluoroethane, at least one compound A and unreacted 1,1,2-trifluoroethane;
- (iii) at least one step of separating the second stream, to give an organic phase P1 comprising the 1-chloro-2,2-difluoroethane, at least one compound A and unreacted 1,1,2-trichloroethane and a nonorganic phase P2 comprising HF;
- (iv) at least one step of purifying the organic phase P1 obtained in (iii);
- wherein step (iv) comprises:
- a) washing the organic phase P1 obtained in step (iii) so as to form an organic phase B1 comprising 1-chloro-2,2-difluoroethane, at least one compound A, unreacted 1,1,2-trichloroethane and 1,1-dichloroethylene;
- and a nonorganic phase B2 comprising hydrofluoric acid;
- b) optionally, drying the organic phase B1 obtained in step a) so as to form an organic phase B3 comprising 1-chloro-2,2-difluoroethane, at least one compound A, unreacted 1,1,2-trichloroethane and 1,1-dichloroethylene;
- c) purifying, preferably by distillation, the organic phase B1 or the organic phase B3 so as to form a stream B4 comprising 1-chloro-2,2-difluoroethane and 1,1-dichloroethylene;
- and an organic phase B5 comprising the unreacted 1,1,2-trichloroethane and at least one compound A.
Dependencies are inferred from the claim text.