METHOD OF EXTRACTION OF SLUDGE CONTAINING METALS OF PLATINUM GROUP Russian patent published in 2002 - IPC

FIELD: extraction of sludge containing metals of platinum group from surfaces of parts in processes using catalysts on base of platinoids; extraction of platinoids from silicon- containing material, for example, silicon network. SUBSTANCE: proposed method includes treatment of silicon-containing materials with solutions of ammonium fluoride and/or hydrofluoride at temperature of 50 to 90 C at blowing the reaction mixture with air till dissolving to silicon-containing materials and separation of sludge containing platinoids. After separation of sludge, solution is neutralized with ammonium; silicon dioxide sediment is separated by filtration and mother liquor is returned for treatment of silica network. EFFECT: possibility of completely extracting platinoids from porous silicon-containing materials in form of sludge containing up to 60% of platinoids by closed process scheme accompanied by production of silicon filler as additional product. 2 cl, 1 tbl, 4 ex