Verfahren zur Herstellung von Alkalicyanid und Siliciumdioxid

摘要

Alkali metal silicates are reacted with HCN in aqs. soln and the resulting silica and residual silicates are precipitated in a methanol-water mixture in which the cyanides are soluble. The cyanides are separated off and concentrated. The silica is washed free of silicates and cyanides in warm acid. The process is economic with little waste material.