Process for the purification of 1,1,1,2-tetrafluoroethane
AssigneeElf Atochem S.A.
InventorsBernard Cheminal, Andre Lantz
Life of this patent
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Abstract
To remove the unsaturated impurities (in particular 1-chloro-2,2-difluoroethylene and polyfluoropropenes) present in crude 1,1,1,2-tetrafluoroethane (F134a), a gaseous mixture of crude F134a, of hydrofluoric acid and of chlorine is treated in gaseous phase in the presence of a fluorination catalyst at a temperature of between 100.degree. and 300.degree. C. and at a pressure between atmospheric pressure and 2.5 MPa, the molar ratio HF/F134a being between 0.05 and 0.5 and the molar ratio Cl.sub.2 /F134a between 0.0001 and 0.1.
Claims14
Process for the purification of a crude 1,1,1,2-tetrafluoroethane (F134a) containing unsaturated impurities, comprising treating a gaseous mixture of crude 1,1,1,2-tetrafluoroethane, of hydroluoric acid and of chlorine in gaseous phase at a temperature of between 150.degree. and 275.degree. C. and at a pressure ranging from atmospheric pressure up to 2.5 MPa, in the presence of a fluorination catalyst, the molar ratio HF/F134a being between 0.05 and 0.5 and the molar ratio Cl.sub.2 /F134a being between 0.0001 and 0.1.
Process for the purification of a crude 1,1,1,2-tetrafluoroethane (F134a) containing unsaturated impurities, comprising treating a gaseous mixture of crude 1,1,1,2-tetrafluoroethane, of hydrofluoric acid and of chlorine in gaseous phase at a temperature of between 100.degree. and 300.degree. C. and at a pressure ranging from atmospheric pressure up to 2.5 MPa, in the presence of a fluorination catalyst based on nickel, the molar ratio HF/F134a being between 0.05 and 0.5 and the molar ratio Cl.sub.2 /F134a being between 0.0001 and 0.1.
Process for the purification of a crude 1,1,1,2-tetrafluoroethane (F134a) containing unsaturated impurities, comprising treating a gaseous mixture of crude 1,1,1,2-tetrafluoroethane, of hydrofluoric acid and of chlorine in gaseous phase at a temperature of between 100.degree. and 300.degree. C. and at a pressure ranging from atmospheric pressure up to 2.5 MPa, in the presence of a fluorination catalyst based on iron, manganese, cobalt and/or zinc, the molar ratio HF/F134a being between 0.05 and 0.5 and the molar ratio Cl.sub.2 /F134a being between 0.0001 and 0.1.
Dependencies are inferred from the claim text.