PURIFICATION METHODS FOR NATURAL DIATOMACEOUS EARTH AND HIGH-PURITY SILICA OBTAINED THEREFROM

摘要

PURPOSE: A purification method for natural diatomaceous earth and high-purity silica obtained therefrom are provided to purify the high purity silica having the purity of 99.99~99.999% from the diatomaceous earth by analyzing the containing property and kinds of the impurity contained in the diatomaceous earth which is natural silica mineral accurately. CONSTITUTION: The purification method for natural diatomaceous earth includes the steps of: adding alkali water solution to the shattered diatomaceous earth raw material; obtaining silicate water solution by melting the silica component; lowering pH to 11~13 by adding acid to the silicic acid solution and filtering it; precipitating silica by lowering pH to 9~11 by adding acid to the filter liquor and filters silica; yielding the silica by washing and heat-treating the filtered silica.