METHOD OF RECYCLING WASTES OF SEMICONDUCTIVE GALLIUM COMPOUNDS Russian patent published in 2015 - IPC C22B58/00 C22B7/00 C22B3/04 C25C1/22 

FIELD: chemistry.

SUBSTANCE: wastes are mixed with saltpetre and soda in ratio 1:(1-1.25):(1-1.25), theoretically required for oxidation reaction. After that, heating is performed first to 200-300°C, with further, after an hour, heating to temperature 460-500°C. Cake is cooled, crushed and leached in water at temperature 20-30°C, arsenous solution is separated, and gallium cake is leached in 13-19% alkali solution at temperature 60-80°C. Filtered from insoluble residue solution is cooled to 15°C and admixture of sodium phosphate is filtered; gallium solution is supplied to electrolysis.

EFFECT: elimination of harmful emissions, reduction of gallium oxide sublimation and reduction of gallium output into circulating industrial product.

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