MINERAL DESILICONIZATION PROCESS Russian patent published in 2008 - IPC C01B33/00 C01B33/10 

FIELD: mineral processing.

SUBSTANCE: invention relates to desiliconization-involving processing of various minerals and ores to produce amorphous silica. Mineral desiliconization process comprises crushing mineral material, fluorination with fluoroammonium compound on heating and subsequent heat treatment of perfluorinated product. Fluoroammonium compound is, in particular, ammonium hydrodifluoride used in amount ensuring molar ratio of thus formed ammonium hexafluorosilicate to unreacted supplementary silicon dioxide (0.5-5.0):1 in reaction mixture. Subsequent heat treatment is effected at 220-320°C. Invention allows power demand in the processing to be reduced, ensures high degree of desiliconization for a large number of mineral objects, increases purity and dispersity of silica obtained, enables separate sublimation of fluoroammonium compound resulting in separation thereof from remaining perfluorinated mass of mineral.

EFFECT: enhanced process efficiency and increased quality of product.

2 cl, 1 tbl, 3 ex