PROCESS FOR CLEANING RARE-EARTH PHOSPHATE CONCENTRATE OF PHOSPHORUS Russian patent published in 1994 - IPC

FIELD: cleaning of rare-earth phosphate concentrates. SUBSTANCE: the cleaning of phosphorus is effected by binding it into insoluble compounds with titanium or zirconium by treatment with titanyl sulfate solutions at a titanium dioxide to phosphorus pentoxide molar ratio of 3.4-3.6:1 or with zirconyl nitrate solutions or solutions resulting from nitric acid decomposition of an eudialyte concentrate at a zirconium dioxide to zirconium pentoxide molar ratio of 1.5-1.8:1, in the presence of nitric acid used on an amount required to decompose the concentrate at a 1.5-1.8:1 molar ratio of zirconium dioxide in the concentrate and phosphorus pentoxide in the solution. EFFECT: improved properties of the rare-earth concentrate. 1 tbl