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 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: 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: A lithium ion secondary cell having a high capacity, improved first charge/discharge efficiency and improved cycle performance is obtainable using as the negative electrode material a lithium-containing silicon oxide powder having the formula: SiLixOy wherein x and y are 0<x<1.0 and 0<y<1.5, with the lithium being fused and partially crystallized.

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: A metallic silicon-containing composite in which metallic silicon nuclei are coated with an inert material which does not contribute to adsorption and desorption of lithium ions is a useful negative electrode material for lithium ion secondary batteries. Using the composite as a negative electrode active material, a lithium ion secondary battery having a high capacity and excellent cycle performance can be fabricated.

Abstract: A metal carbide in microparticulate form is produced by causing an organometallic compound having a polymerizable reactive group to be sorbed to graphite, thermally stabilizing the organometallic compound into a substantially non-volatile polymer within the graphite through hydrolytic condensation, thermal polymerization or catalytic polymerization, and heat treating the polymer at a temperature of at least 1300° C. in a non-oxidizing atmosphere.

Abstract: A C/Si/O composite material having improved oxidation resistance is prepared by impregnating graphite with a crosslinkable silane or siloxane, causing the silane or siloxane to crosslink within the graphite, and heating at 300-1,200° C. in a non-oxidizing gas. The C/Si/O composite material can be efficiently prepared through simple steps, on an industrial scale and at a low cost and will find use as a high-temperature structural material by virtue of oxidation resistance.

Abstract: 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.

Abstract: A silicon oxide powder represented by the formula: SiOx wherein 1.05≦x≦1.5 and having a BET specific surface area of 5-300 m2/g is useful as a negative electrode material to construct a lithium ion secondary cell having a high capacity and improved cycle performance.

Abstract: A non-aqueous electrolyte secondary battery negative electrode material is provided wherein a negative electrode active material containing a lithium ion-occluding and releasing material which has been treated with an organosilicon base surface treating agent is surface coated with a conductive coating. Using the negative electrode material, a lithium ion secondary battery having a high capacity and improved cycle performance is obtainable.

Abstract: 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.

Abstract: A fine &bgr;-silicon carbide powder is prepared by impregnating graphite with an organosilicon compound selected from crosslinkable silanes and siloxanes, causing the organosilicon compound to crosslink within the graphite, and heating at 1,300° C. or higher in an inert gas stream for reaction. Using only low-temperature heat treatment in air and high-temperature heat treatment in inert gas, the invention enables industrial, economical manufacture of fine silicon carbide powder in a stable manner.

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: Silicon oxide containing active silicon represented by the general formula: SiOx wherein x is from 0.8 to 1.9, when analyzed by solid state NMR (29Si DD/MAS) with a sufficient relaxation time set, exhibits a spectrum having two separate peaks, a broad peak (A1) centered at −70 ppm and a broad peak (A2) centered at −110 ppm, the area ratio A1/A2 being in the range of 0.1≦A1/A2≦1.0.

Abstract: In the synthesis of organohalosilanes by the direct process of reacting an organic halogen with metallic silicon powder, a metallic copper catalyst in the form of a thermally active metallic copper powder having large strain energy is used.

Abstract: A conductive powder having an organic silicon polymer layer on the surface of each particle and a metal layer enclosing the silicon polymer layer possesses a stronger bond between the particle base and the metal even at elevated temperature and exhibits a high and stable conductivity and heat resistance.

Abstract: A conductive silicon composite in which particles of the structure that silicon crystallites are dispersed in silicon dioxide are coated on their surfaces with carbon affords satisfactory cycle performance when used as the negative electrode material in a non-aqueous electrolyte secondary cell.

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: A conductive silicon oxide powder in which particles of silicon oxide having the formula: SiOx wherein 1≦x<1.6 are covered on their surfaces with a conductive carbon coating by chemical vapor deposition treatment is useful as a negative electrode active material to construct a lithium ion secondary cell having a high capacity and improved cycle performance.