Abstract: The present invention addresses the problem of evaluating the hydrophobicity of a powder. According to the present invention, a powder is charged into a mixed solvent composed of a lipophilic solvent and a hydrophilic solvent, the voltage rate R of the mixed solvent is measured at predetermined time intervals while adding a lipophilic solvent to the mixed solvent charged with the powder, a parameter x correlating with the concentration of powder is defined for an arbitrary voltage rate R, a continuous function HP(x) of the ratio of a lipophilic solvent corresponding to x is defined, and HP(x) for required x is set as a representative value of a lipophilic solvent ratio distribution and used as an index of hydrophobicity.

Abstract: The present invention addresses the problem of evaluating the hydrophobicity of a powder. According to the present invention, a powder is charged into a mixed solvent composed of a lipophilic solvent and a hydrophilic solvent, the voltage rate R of the mixed solvent is measured at predetermined time intervals while adding a lipophilic solvent to the mixed solvent charged with the powder, a parameter x correlating with the concentration of powder is defined for an arbitrary voltage rate R, a continuous function HP(x) of the ratio of a lipophilic solvent corresponding to x is defined, and HP(x) for required x is set as a representative value of a lipophilic solvent ratio distribution and used as an index of hydrophobicity.

Abstract: A silicon oxide material having a cobalt content of 2-200 ppm is provided. A negative electrode is formed using the silicon oxide material as active material. A nonaqueous electrolyte secondary battery constructed using the negative electrode exhibits improved cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide.

Abstract: Particulate silicon oxide having a Cu content of 100-20,000 ppm, an Fe content of 20-1,000 ppm, an Al content of up to 1,000 ppm, an average particle size of 0.1-30 ?m, and a BET specific surface area of 0.5-30 m2/g is used as negative electrode material in constructing a nonaqueous electrolyte secondary battery. The secondary battery is improved in cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide.

Abstract: A silicon oxide material having a cobalt content of 2-200 ppm is provided. A negative electrode is formed using the silicon oxide material as active material. A nonaqueous electrolyte secondary battery constructed using the negative electrode exhibits improved cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide.

Abstract: Particulate silicon oxide having a Cu content of 100-20,000 ppm, an Fe content of 20-1,000 ppm, an Al content of up to 1,000 ppm, an average particle size of 0.1-30 ?m, and a BET specific surface area of 0.5-30 m2/g is used as negative electrode material in constructing a nonaqueous electrolyte secondary battery. The secondary battery is improved in cycle performance while maintaining the high battery capacity and low volume expansion of silicon oxide.

Abstract: 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° C. in an inert gas atmosphere.

Abstract: 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.

Abstract: 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.

Abstract: 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 0.2–8 wt % of tin and 4–20 wt % of phosphorus which is powdered by atomization.

Abstract: 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° C. in an inert gas atmosphere.

Abstract: In a Rochow process, organohalosilanes are prepared by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst and a co-catalyst. The invention uses as the co-catalyst a powder of co-catalyst active element-copper alloy containing substantial strain energy because this co-catalyst can reduce the activation time taken until a steady state is reached, which has been an outstanding problem in Rochow reaction, maintain the steady state over time and increase the selectivity of desired diorganodihalosilane for eventually increasing the yield based on the starting silicon.

Abstract: 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.

Abstract: 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 0.2-8 wt % of tin and 4-20 wt % of phosphorus which is powdered by atomization.

Abstract: 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.

Abstract: 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.

Abstract: 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: [R2R3R4P—]+Y− wherein R2, R3 and R4 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.

Abstract: 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.

Abstract: 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: [R2R3R4P—]+Y− wherein R2, R3 and R4 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.

Abstract: 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.