Shin-etsu Chemical Co., Ltd.

Shin-estu Chemical Co., Ltd.

Hajime Ishizaka

Mikio Aramata

Tetsuya Inukai

Susumu Ueno

Toshio Shinohara

Yoichi Tanifuji

Yukinori Satou

Ryuichi Saito

Masaaki Furuya

Masahiro Yuyama

Tatsuya Fujimoto

Kenji Saito

Organohalosilanes are prepared by charging a reactor with a contact mass comprising metallic silicon and a catalyst and feeding an organohalide-containing gas to the reactor. The contact mass is prepared by premixing metallic silicon and a tin compound and heat treating the premix at 300-600&#xb0; C. in an inert gas atmosphere.

Making of contact mass for organohalosilane preparation and preparation of organohalosilanes

Organohalosilanes are prepared by charging a reactor with a contact mass of metallic silicon and a catalyst and feeding an organohalide-containing gas to the reactor. Tin or a tin compound is used as the catalyst. Then organohalosilanes can be produced quite efficiently at a high reaction rate while maintaining a low T/D ratio and minimizing the deposition of by-products and carbon.

Preparation of organohalosilanes

Organohalosilanes are prepared by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst. A contact mass composed of metallic silicon and copper catalyst contains an effective amount of a catalyst powder obtained by mechanical surface treatment of a powder mixture of tin powder and another metal, typically copper powder, on a ball mill, stamp mill, jet mill, mechanofusion device or the like.

Organohalosilanes are prepared by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst. A contact mass composed of the metallic silicon and the copper catalyst contains an effective amount of a catalyst alloy containing 0.2&#x2013;8 wt % of tin and 4&#x2013;20 wt % of phosphorus which is powdered by atomization.

In an industrial process for preparing organohalosilanes by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst, a contact mass composed of the metallic silicon and the catalyst further contains an effective amount of a phosphine chalcogenide compound. The invention drastically increases the silane formation rate and the utilization of silicon without lowering the selectivity of useful silane.

When oganohalosilanes are prepared by charging a reactor with a contact mass containing metallic silicon and a copper catalyst, and introducing an organohalide-containing gas feed into the reactor, the partial pressure of organohalide gas in the gas feed is manipulated so as to keep the temperature within the reactor substantially constant. The precise control of reactor internal temperature ensures that organohalosilanes with a higher useful silane content are produced in a safe and inexpensive manner and in high yields from the contact mass having perpetually changing reactivity.

In an industrial process for preparing organohalosilanes by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst, a contact mass composed of the metallic silicon and the catalyst further contains an effective amount of a phosphonium compound having on the molecule at least one group of the formula: &lsqb;R R R P&mdash;&rsqb; Y wherein R , R and R each are a monovalent hydrocarbon group and Y is a halogen atom or acid group. The invention drastically increases the silane formation rate and the utilization of silicon without lowering the selectivity of useful silane.

In a process for preparing oganohalosilanes by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst, a contact mass composed of the metallic silicon and the catalyst further contains a minute, but effective amount of a catalytic metal powder which has been produced by an atomizing technique. The process is successful in drastically increasing a formation rate without lowering the selectivity of useful silane.

When oganohalosilanes are prepared by charging a reactor with a contact mass containing a metallic silicon powder, a copper catalyst and a co-catalyst, and introducing an organohalide-containing gas into the reactor to effect the direct reaction, the catalyst and/or co-catalyst used in the contact mass is obtained by mixing particles of the catalyst and/or co-catalyst with finely divided silica, and applying shear forces to the mixture for mutually rubbing the particles, thereby producing the catalyst and/or co-catalyst having finely divided silica fused to surfaces thereof. The invention is successful in producing organohalosilanes at a significantly improved formation rate without reducing the proportion of diorganodihalosilane.

When oganohalosilanes are prepared by charging a reactor with a contact mass containing metallic silicon and a copper catalyst and introducing an organohalide-containing gas into the reactor to effect the direct reaction, 50-10,000 ppm of bronze phosphide is added to the contact mass. The invention is successful in efficiently producing organohalosilanes in a high STY and low T/D.

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Annaka, Japan

Hajime Ishizaka