Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Hitachi Engineering Services Co., Ltd.

Toshio Ohi

Hiromoto Ohno

Tetsuo Nakajo

Tatsuharu Arai

Haruaki Ito

Yusaku Takita

Kazuo Muramaki

Kazunari Kaga

Fanil Makhmutov

Takami Ohe

Masatoshi Hotta

Hidetoshi Nakayama

Makoto Miyamura

Koichi Nishimura

Shin Tamata

Yuji Sakai

Katsutoshi Morinaka

Nobutoshi Sasaki

Toshitaka Hiro

Toru Tsubaki

Hidejiro Yokoo

Itsuaki Matsuda

Ryuichi Tachi

Yoshiharu Mizuno

Tsunekichi Kuriyama

Yasuaki Toyomasu

Yoshitaka Shohji

Kiyoshi Nomura

Koji Ito

Akio Nadamura

The present invention relates to a method for producing monosilane and tetraalkoxysilane comprising subjecting alkoxysilane represented by formula (1)HSi(OR)&#x2003;&#x2003;(1)wherein R represents alkyl group having 1 to 6 carbon atoms and n represents an integer of from 1 to 3, to disproportionation reaction in a gaseous phase in the presence of an inorganic phosphate or a catalyst having a specific chemical structure based on a heteropolyacid salt structure. In the production method of the present invention, separation from the solvent can be carried out easily, the reaction proceeds quickly and the conversion rate of the starting materials is high.

Method for producing monosilane and tetraalkoxysilane

The present invention relates to method for producing monosilane and tetraalkoxysilane comprising subjecting alkoxysilane represented by formula (1)HSi(OR)&#x2003;&#x2003;(1)wherein R represents alkyl group having 1 to 6 carbon atoms and n represents an integer of from 1 to 3, to dismutation reaction in a gaseous phase in the presence of a catalyst containing an alkali metal fluoride and a catalyst activator. The method can solve problems in a method for producing monosilane and tetraalkoxysilane by dismutation reaction of alkoxysilane in a liquid phase: i.e. problems such that separation from the solvent is difficult and that the reaction is too slow and not suitable for industrial production.

There is provided a fluorine-containing compound purification method for obtaining a high-purity fluorine-containing compound by efficiently separating and removing hydrogen chloride from a fluorine-containing compound that contains hydrogen chloride, i.e., from a crude fluorine-containing compound. The fluorine-containing compound purification method of the present invention comprises the following steps (1) and (2) in this order:

Fluorine-containing compound purification method

An object of the invention is to provide efficient, simple and inexpensive processes for the production of carbonyl difluoride, which is an attractive and important compound as a semiconductor etching gas or a semiconductor cleaning gas. A process for producing carbonyl difluoride of the invention includes a step of reacting phosgene and hydrogen fluoride in a gas phase in the presence of a fluorination catalyst to produce carbonyl difluoride and hydrogen chloride, and a step of mixing a mixture containing the carbonyl difluoride and the hydrogen chloride with an organic solvent that is azeotropic with hydrogen chloride but zeotropic with carbonyl difluoride, and distilling the resultant mixture to separate the carbonyl difluoride.

Process for producing carbonyl difluoride

It is an object of the present invention to provide a process for producing 1,2,3,4 -tetrachlorohexafluorobutane industrially inexpensively and efficiently by utilizing expensive fluorine gas efficiently and to provide a process which is capable of stably producing 1,2,3,4 -tetrachlorohexafluorobutane and in which, by carrying out fluorination reaction at a low temperature, side reactions such as formation of a low-boiling substance due to cleavage of C&#x2014;C bonds and formation of an excess fluoride are difficult to occur. The process for producing 1,2,3,4-tetrachlorohexafluorobutane of the present invention is characterized in that it includes feeding fluorine gas to 1,2,3,4-tetrachlorobutane using plural reactors in the presence of a solvent and in the absence of a catalyst to allow the 1,2,3,4-tetrachlorobutane and the fluorine gas to react with each other, wherein a part or all of unreacted fluorine gas discharged from one reactor is introduced into a reactor different from said one reactor.

Production process and purification process for 1,2,3,4-tetrachlorohexafluorobutane

The present invention provides a process for producing 1,2,3,4-tetrachlorohexafluorobutane having a high purity at a low cost industrially and efficiently. The process for producing 1,2,3,4-tetrachlorohexafluorobutane according to the present invention comprises a step of allowing 1,2,3,4-tetrachlorobutane to react with a fluorine gas to prepare a reaction product containing 1,2,3,4-tetrachlorohexafluorobutane and hydrogen-containing compounds as an impurity, and a step of introducing the reaction product into single or plural distillation columns and distilling to separate the hydrogen-containing compounds from the reaction product and thereby preparing purified 1,2,3,4-tetrachlorohexafluorobutane wherein the at least one of distillation columns has a theoretical plate number of 15 or more.

Process for producing 1,2,3,4-tetrachlorohexafluorobutane

The production process for 1,2,3,4-tetrachlorohexafluorobutane of the present invention is characterized in that 1,2,3,4-tetrachlorobutane is reacted with fluorine in the presence of a solvent containing hydrogen fluoride. The 1,2,3,4-tetrachlorobutane may be obtained by chlorination of 3,4-dichlorobutene-1. Further, the present invention provides as well a process of refining 1,2,3,4-tetrachlorohexafluorobutane obtained in the manner described above. According to the present invention, 1,2,3,4-tetrachlorohexafluorobutane which is useful, for example, as a synthetic raw material for hexafluoro-1,3-butadiene used as an etching gas for semiconductors can industrially efficiently be produced by using 1,2,3,4-tetrachlorobutane which is a by-product of chloroprene and which has so far been disposed.

Production process for 1,2,3,4-tetrachlorohexafluorobutane and refining process

The production process of the present invention for a chlorine-containing fluorine-containing compound is characterized in that a reaction of adding chlorine atoms to a carbon-carbon unsaturated bond of a hydrogen-containing compound having a carbon-carbon unsaturated bond is carried out under the presence of a fluorine gas. The hydrogen-containing compound having a carbon-carbon unsaturated bond may be 3,4-dichlorobutene-1. Further, the present invention provides a process for producing efficiently and economically 1,2,3,4 -tetrachlorohexafluorobutane from 3,4-dichlorobutene-1 described above. According to the present invention, chlorination and fluorination of the hydrogen-containing compound having a carbon-carbon unsaturated bond are carried out in a single step, and therefore a chlorine-containing fluorine-containing compound can be more economically produced at a higher yield than in a conventional process in which two reactions are individually carried out.

Production process for chlorine-containing fluorine-containing compound

The process for producing a fluorine-containing compound such as 1,2,3,4-tetrachlorohexafluorobutane of the present invention is characterized in that a halogenated hydrocarbon compound such as 1,2,3,4-tetrachlorobutane is brought into contact with fluorine gas in a liquid phase or in a solid-liquid coexistence state in the absence of a solvent and a catalyst. According to the present invention, a fluorine-containing compound is readily produced from a halogenated hydrocarbon compound using neither a reaction solvent nor a reaction catalyst.

A method for producing nitrogen trifluoride related to the present invention is characterized in that a fluorine gas and an ammonia gas are fed into a tubular reactor and are reacted with each other in the presence of a diluting gas in a gaseous phase under the condition of no catalyst to produce a gas product mainly composed of nitrogen trifluoride and a solid product mainly composed of ammonium fluoride and/or acidic ammonium fluoride, and then the solid product attached to an inner wall of the tubular reactor is removed by means of a device for removing the solid product, which device is mounted to the tubular reactor.

Method and apparatus for producing nitrogen trifluoride

Disclosed is a process for producing hexafluoro-1,3-butadiene, which is used for an etching gas capable of being used in fine processing for semiconductors, safely in industrialization and at low cost economically. Specifically disclosed is a process for producing hexafluoro-1,3-butadiene comprises (1) a step comprising allowing a compound having four carbon atoms each which bonds to an atom selected from the group consisting of a bromine atom, an iodine atom and a chlorine atom, to react with a fluorine gas in the presence of a diluting gas in a gas phase, thereby preparing a mixture containing a product (A), and (2) a step comprising eliminating halogens excluding a fluorine atom with a metal from the product (A) prepared in the step (1) in the presence of a solvent, thereby preparing a mixture containing hexafluoro-1,3-butadiene.

Process for producing hexafluoro-1,3-butadiene

Disclosed is a process for producing 1,2,3,4-tetrachlorohexafluorobutane safely in a high yield in the industrial viewpoint and at low cost in the economical viewpoint. Specifically disclosed is a process for producing 1,2,3,4-tetrachlorohexafluorobutane which process comprises: (1) a step of chlorinating 1,3-butadiene, thereby preparing a mixture containing 1,2,3,4-tetrachlorobutane, and (2) a step of allowing the 1,2,3,4-tetrachlorobutane prepared in the step (1) to react with a fluorine gas in the presence of a diluting gas in a gas phase, thereby preparing a mixture containing 1,2,3,4-tetrachlorohexafluorobutane.

A process for production of high-purity hexafluoroethane, wherein a mixed gas containing hexafluoroethane and chlorotrifluoromethane is reacted with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst at 200&#x2013;450&#xb0; C., for fluorination of the chlorotrifluoromethane, or wherein pentafluoroethane containing chlorine compounds with 1&#x2013;3 carbon atoms is reacted with hydrogen in a gas phase in the presence of a hydrogenation catalyst at 150&#x2013;400&#xb0; C., and the product is then reacted with fluorine in a gas phase in the presence of a diluent gas.

Production and use of hexafluoroethane

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.

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Kawasaki, Japan

Toshio Ohi