| 摘要 |
Production of an alkali, alkaline earth or rare earth metal silicate (I) involves reacting silica and the corresponding metal sulfate in a reactor provided with burner(s) immersed in the molten mass and fed with oxygen-containing gas, where an excess (based on consumed oxygen) of reducing fuel is introduced into the reactor. - An INDEPENDENT CLAIM is included for the preparation of precipitated silica (II), involving: - (1) preparing (I) as above, using a reactor provided with a flue having a system for recovery of sulfur oxides forming sulfuric acid; and - (2) leaching the obtained (I) with the sulfuric acid formed in the first step, to form (I) (specifically having a particle size of 0.5-300 nm) and the metal sulfate, which is recycled to the production of (I). |
