Method for preparation of silica SiO2 from serpentinite raw material

摘要

Method for producing silicon dioxide SiO2 from serpentinite raw material and HCl is carried out so that the serpentine raw material having particle size up to 0.3 mm and containing up to 43.4 % of silica (SiO2), up to 43.6 % of magnesium oxide (MgO) and oxides of metal elements such as aluminum (Al), iron (Fe), calcium (Ca), titanium (Ti), manganese (Mn), nickel (Ni), cobalt (Co), chromium (Cr), sodium (Na), potassium (K, etc. chemically reacts with 15 to 23 % hydrochloric acid (HCl) at atmospheric pressure and temperature from 45 to 55 °C while stirring the suspension. This results in a solid product containing at least 98 % of silica (SiO2), impurified mainly with alumina and residual chromite, and a liquid product comprising mainly magnesium chloride (MgCl2) and other soluble chlorides of some accompanying elements.