When phosphate rock is leached with hydrochloric acid, radium can be removed by co-precipitation with Bao.4Ca,.6S04 and uranium by extraction with a 5% solution of tributylphosphate in hexane or Varsol. Phosphoric acid is then separated from calcium chloride solution and other impurities by extraction with undiluted tributyl phosphate. The lanthanides can be precipitated from the raffinate by NH,, and CaS0,.2H20 by H2S04 to regenerate HCl for recycle. The organic phase containing H,PO, can be stripped by NH, to yield ammonium phosphate and to regenerate the tributyl phosphate for recycle. Fluorine can be precipitated from the initial leach solution as Na2SiF6.
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