Abstract: The invention relates to a process for the preparation of 1-chloro-1-fluoroethane and 1,1-difluoroethane by reaction of vinyl chloride with hydrogen fluoride, in an organic solvent consisting of at least one saturated halogen-containing hydrocarbon.

Abstract: The invention relates to a process for the preparation of 1-chloro-1-fluoroethane and 1,1-difluoroethane by reaction of vinyl chloride with hydrogen fluoride, in an organic solvent consisting of at least one saturated halogen-containing hydrocarbon.

Abstract: The invention relates to a process for the preparation of chloro-1-fluoroethane and 1,1-difluoroethane by reaction of vinyl chloride with hydrogen fluoride, in organic solvent consisting of at least one saturated halogen-containing hydrocarbon.

Abstract: Hydrogenation catalysts based on palladium, platinum or rhodium comprising at least one other metal M which are deposited on zirconium oxide and silicon oxide supports. Process for the manufacture of these catalysts by successive impregnation of the support using palladium, platinum or rhodium and using another metal M. Use of these catalysts in hydrogenation reactions and in particular in preparing hydrogen peroxide.

Abstract: Process for manufacturing a purified aqueous hydrogen peroxide solution, in which a crude aqueous hydrogen peroxide solution is subjected to a washing operation with at least one organic solvent which has been subjected to a purification treatment prior to the washing operation. Aqueous hydrogen peroxide solution with a TOC, defined according to ISO standard 8245, of less than or equal to 72 mg/l.

Abstract: Process for the hydrofluorination of chloro(fluoro)butane of general formula C.sub.4 H.sub.5 Cl.sub.x F.sub.5-x in which x=1 to 5, by means of hydrogen fluoride and in the presence of a catalyst chosen from the derivatives of metals of groups IIIa, IVa, IVb, Va, Vb and VIb of the Periodic Table of the elements.

Abstract: 1,1,1-Trifluoroethane is produced, in addition to 1,1,-dichloro-1-fluoroethane and/or 1-chloro-1,1-difluoroethane, by hydrofluorination in the liquid phase, using hydrogen fluoride, vinylidene fluoride and at least one chloro compound chosen from vinylidene chloride and 1,1,1-trichloroethane.

Abstract: 1,1,1-Trifluoroethane (HFC-143a) is produced in the liquid phase by reaction between vinylidene fluoride and hydrogen fluoride, in the absence of catalyst.

Abstract: The invention relates to compositions comprising 1,1,1,3,3-pentafluorobutane and ethanol. These compositions can be used especially as solvents for cleaning electronic components and for degreasing metals.

Abstract: Purification of crude 1,1-difluoroethane (HFA-152a) from vinyl chloride, by bringing into contact with an active carbon.

Abstract: Process for the preparation of 1,1,1,2-tetrafluoroethane by reaction of hydrogen fluoride with a trihaloethylene according to which trifluoroethylene is chosen as trihaloethylene and the reaction is carried out in the liquid phase.

Abstract: The invention relates to a process for preparing 1,1-dichloro-1,3,3,3-tetrafluoropropane by reacting, in the liquid phase, 1,1,1,3,3,3-hexachloropropane with hydrogen fluoride, in the presence of a catalyst.

Abstract: Process for the preparation of .beta.-hydroxybutyric acid esters, comprising:1) a step involving alcoholysis of the polyhydroxybutyrate in the presence of an alcohol, a halogenated solvent, and an acid,2) a neutralization step comprising the addition of an alcoholate in solution in the alcohol,3) a purification step comprising the addition of a halogenated solvent and the azeotropic removal of water and the alcohol,4) a step for recovery of the ester, comprising a filtration, a distillation of the halogenated solvent and a distillation of the ester.This process enables .beta.-hydroxybutyric acid esters of high purity to be obtained.