METHOD OF PREPARING AQUEOUS SILICA SOL SOLUTION FROM SILICEOUS MUDSTONE

摘要

A process technique for preparing silica sol that can be used in high-tech fields using, as a raw material, siliceous mudstone that is mineral resources is provided. A method of preparing an aqueous silica sol solution from siliceous mudstone comprises: a water removal step(S50) of subjecting siliceous mudstone to heat treatment to remove water contained in the siliceous mudstone; an impurity removal step(S60) of removing impurities from the siliceous mudstone; a dissolution step(S100) of leaching with sodium hydroxide of the siliceous mudstone to dissolve silica into sodium silicate; an ion exchange step(S200) of eliminating sodium from the aqueous sodium silicate solution with ion exchange to prepare aqueous silicic acid solution; an adjusting step(S300) of adjusting pH of the aqueous silicic acid solution using ammonium hydroxide to stabilize the aqueous silicic acid solution; and a processing step(S400) of processing the stabilized aqueous silicic acid solution using sol-gel reaction.