Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Hitachi Engineering Services Co., Ltd.

Hiromoto Ohno

Toshio Ohi

Tatsuharu Arai

Tetsuo Nakajo

Kazunari Kaga

Haruaki Ito

Yusaku Takita

Kazuo Muramaki

Fanil Makhmutov

Takami Ohe

Masatoshi Hotta

Hidejiro Yokoo

Hidetoshi Nakayama

Makoto Miyamura

Shin Tamata

Yuji Sakai

Katsutoshi Morinaka

Nobutoshi Sasaki

Toru Tsubaki

Itsuaki Matsuda

Shiho Irie

Kiyoshi Nomura

Ryuichi Tachi

Yoshitaka Shohji

Koichi Katamura

Sadayoshi Yuge

Haruyuki Kawai

Yasuaki Morito

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

An efficient process is provided in which sulfur is reacted with carbon monoxide in a liquid phase to produce carbonyl sulfide. In the presence of a base catalyst, carbon monoxide is continuously introduced into a reactor in which a liquid reaction mixture obtained by dissolving or suspending sulfur in an organic solvent is held, and the sulfur is reacted with the carbon monoxide at a pressure of 0.2-3.0 MPa and a temperature of 40-120&#xb0; C. to yield carbonyl sulfide. The gaseous-phase part is withdrawn from the reactor, and the withdrawn gaseous-phase part is cooled with a cooler to condense the carbonyl sulfide contained in the gaseous-phase part. The condensed carbonyl sulfide is continuously withdrawn, and the gas that has not been condensed with the cooler is returned to the reactor. Thus, carbonyl sulfide is continuously produced.

Process for producing carbonyl sulfide

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.

The process for recovering pentafluoroethane of the invention includes bringing a mixed gas containing pentafluoroethane and a non-condensable gas into contact with a chlorinated solvent, and allowing the chlorinated solvent to absorb pentafluoroethane contained in the mixed gas. The process for the production of pentafluoroethane of the invention uses the recovering process.

Process for recovering pentafluoroethane, and production method of pentafluoroethane involving the process

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.

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Kawasaki, Japan

Hiromoto Ohno