METHOD OF PROCESSING MONAZITE RAW MATERIALS Russian patent published in 2018 - IPC C22B59/00 C22B60/02 C22B1/06 C22B3/04 

FIELD: technological processes.

SUBSTANCE: invention relates to the technology of rare and radioactive elements and can be used to obtain concentrates of rare and rare-earth elements from monazite. Method for processing monazite raw material includes opening the concentrate with molten ammonium bifluoride at a temperature of 195–230 °C for 1.5–2 hours. Resulting fluoride powder is heated with 94–96 % sulfuric acid taken with an excess of 5–10 % at 290–310 °C for 1.5 hours. Resulting sulphate powder is dissolved at 20–80 °C in water for two hours, followed by precipitation of metal hydroxides. Resulting gases after opening are sent for condensation to separate ammonium bifluoride, the resulting ammonium sulfate and silicon tetrafluoride are fed to produce ammonium bifluoride and white carbon, and precipitation of metal hydroxides is carried out in two stages: at pH 5.4–5.6 for precipitation of hydroxides U, Th, Fe, Zr, Ti, Al and at pH 6.4–6.7 for precipitation of REE hydroxides.

EFFECT: technical result is a reduction in the number of technological redistribution processes of the processing of monazite raw materials with a REE recovery rate of not less than 98_7 %.

4 cl, 3 ex