PARTICLES FORMED OF SILICA AND CARBON, AND METHOD FOR PRODUCING MIXTURE OF SILICA AND CARBON

摘要

Provided are particles which are formed of silica and carbon and have low impurity content and excellent reactivity. Particles which are formed of silica and carbon and contain B and P respectively in amounts of 1 ppm or less. The silica and carbon are distributed evenly across the inside of each particle. A method for producing a mixture of silica and carbon, said mixture being an assembly of particles that are formed of silica and carbon. This method for producing a mixture of silica and carbon comprises: (B) a carbon mixing step wherein a carbon-containing aqueous alkali silicate solution is obtained by mixing carbon and an aqueous alkali silicate solution that has an Si concentration in the liquid content of 10% by mass or more; and (C) a silica recovery step wherein after obtaining a particle-containing liquid material by mixing a mineral acid with the carbon-containing aqueous alkali silicate solution that has been obtained in step (B) so that C and Si in the liquid content are precipitated as particles that are formed of silica and carbon, the liquid material is subjected to solid-liquid separation, thereby obtaining a solid content that contains a mixture of silica and carbon, said mixture being an assembly of particles that are formed of silica and carbon, and a liquid content that contains impurities.