The optimum defluorinating conditions for Sichuan bastnasite crude ore were determined by orthogonal experiments. Over 95 per cent fluorine in the crude ore was stripped by roasting 30 minutes of the crude ore with Na_2CO_3/ore=0.25 at 650degC. The stripped fluorine crude ore was further treated by NH_4Cl to recover rare earth. Above 95 per cent rare earth can be leached by water after the stripped fluorine crude ore mixed NH_4Cl(NH_4Cl/ore-1:1) roasted l h at 325degC. At the same time, the rare earth leaching solution contains little Fe, Si and Al. Therefore it is propitious to further purify the solution and recover rare earth.
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