Central Glass Company, Limited

Hideki Oshio

Toshikazu Kawai

Satoshi Yoshikawa

Takeshi Kondo

Kiyoshi Yagii

Naoto Takada

Minoru Aramaki

Masamichi Maruta

Kimiaki Matsuoka

Tadaaki Komatsu

Katsuyoshi Murata

Hirokazu Takeda

Sadaharu Mishumi

The invention relates to a method of preparing a saturated hydrofluorocarbon represented by C.sub.n H.sub.p F.sub.z, by reducing a chlorofluorocarbon or hydrochlorofluorocarbon represented by C.sub.n H.sub.x Cl.sub.y F.sub.z by hydrogen in the presence of a catalyst having palladium and bismuth, wherein 'n' is an integer within a range from 3 to 6, 'x' is an integer within a range from 0 to 2n, each of 'y' and 'z' is an integer within a range from 1 to 2n+1, x+y+z=2n+2 or 2n, p=x+y when x+y+z=2n+2, and p=x+y+2 when x+y+z=2n. The catalyst has a long lifetime in the reduction. According to the invention, conversion of the chlorofluorocarbon or hydrochlorofluorocarbon is high, and the saturated hydrofluorocarbon is prepared with a high yield and a high selectivity.

Method of preparing hydrofluorocarbon

1,1,1,2-Tetrafluoroethane, a refrigerant, is formed with little formation of isomers or chlorofluoroethanes having not very different boiling points by reacting 1,1-dichloro-1,2,2,2-tetrafluoroethane (R-114a), which may contain up to about 25 wt% of 1,2-dichloro-1,1,2,2-tetrafluoroethane (R-114), with hydrogen gas in the presence of a palladium-on-active alumina catalyst at a temperature lower than 200.degree. C. and not lower than 120.degree. C. R-114a almost free of R-114 is obtained by reacting 1,1,1-trichloro-2,2,2-trifluoroethane with hydrogen fluoride in vapor phase in the presence of a catalyst prepared by partially fluorinating .gamma.-alumina by treatment with hydrogen fluoride gas.

Method of preparing 1,1,1,2-tetrafluoroethane from

A novel compound, trifluoromethylbenzoyl bromide, is formed by bromination of trifluoromethylbenzoic acid with, e.g., phosphorus tribromide or by halogen exchange reaction of trifluoromethylbenzoyl chloride with bromine in the presence of a metal bromide. Decarbonylation of 2-, 3- or 4-trifluoromethylbenozyl bromide using a catalyst such as a phosphine-rhodium complex gives 2-, 3- or 4-bromobenzotrifluoride without forming isomers.

Trifluoromethylbenzoyl bromide and conversion of same to

Dichlorotrifluoromethyltoluenes useful in producing some medicines and agricultural chemicals are formed with good yields by reacting dichlorotrichloromethyltoluenes with hydrogen fluoride usually at 0.degree.-100.degree. C. under pressure of 3-20 kg/cm.sup.2. Besides known 3,4-dichloro-6-trifluoromethyltoluene and 3,4-dichloro-5-trifluoromethyltoluene, novel isomers are also obtained by this method.

Preparation of dichlorotrifluoromethyltoluenes including novel isomers

Trifluoroacetic acid is easily formed by hydrolysis of 1,1,1-trichloro-2,2,2-trifluoroethane with water in the presence of a catalyst comprising an inorganic metal compound, preferably a chloride of Mn, Fe, Co, Ni, Cu or Zn. Preferably the hydrolysis reaction is carried out as a vapor phase contact reaction at 200.degree.-400.degree. C., using 5-15 moles of water per mole of trichlorotrifluoroethane.

Method of preparing trifluoroacetic acid from trichlorotrifluoroethane

A halogenated hydrocarbon such as a halogenated ethane or propane is dehalogenated by subjecting to electrolysis an aqueous reaction system containing the halogenated hydrocarbon, a halide of metal having dehalogenating ability and a detergent. The detached halogen leaves the reaction system in elemental form.

Method of dehalogenating halogenated hydrocarbon to yield elemental

A process for preparing fluorine-rich organic compounds containing one or two carbon atoms from organic fluoro compounds of lower fluorine content in which starting partially or completely halogenated fluoro carbon compounds having at least one halogen atom other than fluorine, e.g., CHCl.sub.2 F, CHClF.sub.2, CCl.sub.2 F.sub.2, CCl.sub.3 F, C.sub.2 Cl.sub.3 F.sub.3, C.sub.2 Cl.sub.2 F.sub.4 and C.sub.2 Cl.sub.4 F.sub.2, are contacted under disproportionation conditions with a catalyst system of a specific type which comprises 0.1 - 5% by weight, as metal, of a nickel(II) halide, titanium(III) chloride or titanium(III) fluoride and a balance of an aluminum compound such as activated alumina, silica, alumina or aluminum fluoride.

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Omiya, Japan

Hideki Oshio