Abstract: A process for the separation of hydrogen fluoride (HF) and of difluoromethane (F32) by fractional distillation and/or condensation, in at least one stage, including in at least one stage obtaining a stream whose HF and F32 contents correspond.

Abstract: The geometric measurement of a vehicle is effected by apparatus comprising a casing (1) with an axle (2) protruding from the casing. The axle (2) is mounted for rotation in the casing (1) and engages with its protruding end and is fixed to a support element (3) secured to a wheel of the vehicle to be inspected. The casing (1) contains a camera block (13) for measuring the orientation of the wheel in the vertical plane, a potentiometer (12) for following the angle of the wheel, a device (11) for measuring inclinations in a vertical plane perpendicular to and in a vertical plane parallel to the wheel, connected to an electronic card (10). The camera block (13), the potentiometer (12) and the device (11) connected to an electronic card (10) emit electrical signals representative of indications correlated with the physical parameters to be detected for the geometrical inspection of a vehicle.

Abstract: The subject of the invention is a continuous process for the preparation of 1,1,1,2-tetrafluoroethane (134a) from 2-chloro-1,1,1-trifluoroethane (133a) and hydrofluoric acid in the gaseous phase in the presence of a chromium-based catalysts.According to the invention, the flow of gas leaving the reactor is subjected to a distillation in order to separate at the top a flow containing almost all the HC1 and at least 90% of the 134a produced by the reaction and at the bottom a flow containing at least 90% of the unconverted reactants (133a and HF), and the latter flow is recycled directly to the reactor, without any purifying operation.

Abstract: The invention relates to continuous production of 1,1,1-chlorodifluoroethane from 1,1,1-trichloroethane and hydrofluoric acid by reaction in liquid phase in the presence of at least one fluorination catalyst. According to the invention, the process is carried out under an absolute pressure of between 6 and 30 bars and at a temperature of between 50.degree. and 120.degree. C., the content of catalyst(s) in the reaction mixture, expressed as a percentage by weight of metal, being between 0.05 and 10% and the content of organohalogenated by-products not belonging to series 140 in the reaction mixture being controlled at a value below 40% by weight. This process makes it possible, at the same time, to obtain a high degree of conversion of hydrofluoric acid, to minimize the coproduction of 1,1,1-trifluoroethane and organohalogenated by-products and to facilitate the recovery of the hydrochloric acid formed.

Abstract: The invention relates to the separation of hydrogen fluoride (HF) from its mixtures with 1,1,1-trifluoro-2-chloroethane (F133a).By settling of the mixture of HF and F133a in the presence of trichloroethylene at a temperature below 0.degree. C., a lower organic phase which is poor in HF and an upper phase which is rich in HF are obtained. The latter can be directly recycled to the fluorination reactor or subjected to a distillation in order to separate, at the head, the HF/F133a azeotrope which is returned to the settler, and to recover, at the foot, practically pure HF. By distillation of the lower phase, the HF/F133a azeotrope which is returned to the settler is separated at the head and a mixture of F133a and trichloroethylene is recovered at the foot. The latter mixture is subjected to a distillation which makes it possible to separate, at the head, pure F133a from trichloroethylene at the foot.