| 摘要 |
FIELD: technological processes.SUBSTANCE: invention relates to methods of producing finely dispersed silicon dioxide. Method of producing silicon dioxide is carried out by leaching of siliceous material while heating with subsequent filtering to obtain a solution of sodium or potassium liquid glass and insoluble part. Solution of sodium or potassium liquid glass is mixed with a solution of a precipitation agent. Precipitation agent used is aqueous solution of magnesium nitrate. Magnesium silicate precipitate formed is separated by filtration from solution of sodium nitrate without flushing and treated with solution of nitric acid to produce silicon dioxide and magnesium nitrate solution. Silicon dioxide is separated by filtration, washed and dried. Technical result is efficient extraction of silica-containing raw materials of silicon dioxide containing SiO- 98.341÷99.859 %. Obtained silicon dioxide has specific surface area 680.5÷731.5 m/g.EFFECT: efficient extraction of silicon dioxide.6 cl, 1 dwg, 1 tbl, 5 ex |
