PRODUCTION OF MAGNESIUM OXIDE FROM MAGNESIUM SILICATES BY BASIC EXTRACTION OF SILICA

摘要

A B S T R A C TThere is provided a process for replacing themagnesium oxide portion of a nature magnesium silicatewith sodium oxide thereby to form sodium silicate whichcomprises melting a natural magnesium silicate andsodium carbonate at a temperature of from 1100 to 1350°Cuntil a clear melt is obtained, the molar ratio ofsodium oxide derived from the sodium carbonate per moleof silica contained in the natural magnesium silicatebeing from 4:1 to 7:1, quenching and extracting saidclear melt with water and separating the insoluble mag-nesium oxide from the solution containing predominantlysodium silicate and sodium hydroxide.