Process for Production of Dichlorotrifluoroethane
AssigneeMexichem Amanco S.A. de C.V.
InventorsClive Robert Giddis, Paul Hendry Stewert
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Abstract
A process for the production of dichlorotrifluoroethane is described. The process comprises reacting perchloroethylene with hydrogen fluoride (HP) at elevated temperature in the vapour phase in at least one reactor in the presence of a fluorination catalyst. The process is operated so that 30 weight % or more of the perchloroethylene reactant that is fed to the at least one reactor remains unreacted having passed through the or each reactor. The dichlorotrifluoroethane may be purified and then used as it is or used to prepare pentafluoroethane.
Claims28
1-65. (canceled)
A process for the production of dichlorotrifluoroethane which comprises reacting perchloroethylene with hydrogen fluoride (HF) at elevated temperatures in the vapour phase in the presence of a fluorination catalyst, wherein the process is conducted using a plurality of reactors that are connected in series with intermediate cooling being employed between each pair of reactors in the series, and further wherein the process is operated so that 30 weight % or more of the perchloroethylene reactant that is fed to the reactors remains unreacted having passed through each reactor.
A process for the production of pentafluoroethane which comprises the steps of:
- (i) in a first reactor or a first plurality of reactors reacting perchloroethylene with hydrogen fluoride in the vapour phase at elevated temperature in the presence of a fluorination catalyst to produce a composition comprising dichlorotrifluoroethane, hydrogen chloride, unreacted perchloroethylene less than 2 weight % of chlorotetrafluoroethane and pentafluoroethane combined and less than 5 weight % of compounds having the formula C2Cl6-xFx, where x is an integer of from 0 to 6, based on the total weight of organic compounds in the composition;
- (ii) subjecting the composition from step (i) to a separation step to yield a purified composition comprising at least 95 weight % of dichlorotrifluoroethane and less than 0.5 weight % of compounds having the formula C2Cl6-xFx, where x is an integer of from 0 to 6, based on the total weight of organic compounds in the composition;
- and
- (iii) in a second reactor or a second plurality of reactors reacting the composition from step (ii) with hydrogen fluoride (HF) in the vapour phase at an elevated temperature in the presence of a fluorination catalyst to produce a composition comprising pentafluoroethane and less than 0.5 weight % of chloropentafluoroethane, based on the total weight of organic compounds in the composition,
- and wherein step (i) of the process is operated so that 30 weight % or more of the perchloroethylene that is fed to the at least one reactor remains unreacted having passed through the or each reactor.
Dependencies are inferred from the claim text.