Showa Denko K.k.

Itsuaki Matsuda

Hiromoto Ohno

Toshio Ohi

Keiji Kawasaki

Kazunari Kaga

Tadao Takase

Tetsuo Takeshita

Ryuichi Tachi

Takeshi Adachi

The present invention provided a method for measuring a halogen gas and/or a hydrofluorocarbon for the purpose of controlling the concentration of the halogen gas and/or the hydrofluorocarbon, in a plant producing a halogen compound or a perfluorocarbon, at a predetermined concentration level quickly, easily, and precisely for the control. The present invention provides also a measurement apparatus for the above measurement which has a compact structure, and in which the parts are exchangeable quickly and readily. The present invention provides further a process for producing a halogen compound or a perfluorocarbon employing the measurement method and the measurement apparatus. In particular, the present invention intends to provide a method for measuring safely and quickly a hydrofluorocarbon concentration in a mixed gas stream in a process of producing a perfluorocarbon by direct fluorination reaction of a hydrofluorocarbon and F.

Measuring method for concentration of halogen and fluorine compound, measuring equipment thereof and manufacturing method of halogen compound

A method for treating an electrolytic diaphragm formed by adhering asbestos fibers to the surface of an electrolytic cathode made of a wire mesh or porous plate, which comprises permeating water glass into the diaphragm, then permeating a chloroprene latex into the water glass-treated diaphragm, and drying the treated diaphragm under heat.

Method for treating electrolytic diaphragm

An improved diaphragm for electrolysis, said diaphragm being composed of a fibrous base material of asbestos or a mixture of asbestos and fluorine-containing fibers and existing in the interstices of said base material, a water-swellable micaceous mineral represented by the following general formula

Diaphragm for electrolysis and method for production thereof

An improved cathode for the electrolysis of an aqueous solution of an alkali metal halide, which shows a reduced hydrogen overvoltage. The cathode comprises a metallic substrate and a coating of iron or both iron and cobalt electroplated thereon from a specified electroplating bath containing iron or both iron and cobalt. A method is also provided for electrolyzing an aqueous solution of an alkali metal halide using this cathode.

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Yokohama, Japan

Itsuaki Matsuda