METHOD OF WATER GLASS PRODUCING Russian patent published in 1994 - IPC

FIELD: chemical technology. SUBSTANCE: method involves the preparing of suspension made of silica gel and water at the ratio of solid:liquid = 1: (1.0-2.5). Then calcium-containing substance (limestone, chalk, lime) is added to the suspension at quantity 11-15% of silica gel mass , and mass is heated up to the boiling. Then alkaline metal hydroxide is added, heated up to the boiling and kept for 15-20 min. Slime is separated after cooling. Composition of water glass, %: Na₂O 6.9-9.1; SiO₂ 20.7-26.7; F^- 0.05-0.07, density is 1,22 - 1,39 g/cm³, module is 2.9-3.1. Method is used in technology of fluosilicic acid waste reprocessing. EFFECT: improved method of water glass producing. 2 cl