PROCESS FOR THE TOTAL RECOVERY OF URANIUM,RARE EARTHS,THORIUM AND YTTRIUM FROM AN ACID AQUEOUS SOLUTION BY EXTRACTION

摘要

1. A continuous process for the total recovery of uranium IV and/or VI, thorium, yttrium and rare earths contained in an acid aqueous starting phase which is a crude wet-process phosphoric acid or else which was produced either from a residual phosphogypsum containing said metal species in an insoluble state by treatment by means of a strong inorganic acid in aqueous solution, or as an aqueous raffinate from extraction with water-insoluble or weakly water-soluble solvents of a crude wet-process phosphoric acid, characterised in that said acid aqueous solution is brought into contact with a homogenous organic phase comprising a di-(alkylphenyl) phosphoric acid which is free from mono-(alkylphenyl) phosphoric derivative and an inert organic solvent selected from aliphatic or aromatic hydrocarbons used alone or in the form of a mixture, whereby, as the result, after separation of the phases, there are collected a substantially exhausted aqueous phase and an organic phase charged with uranium, thorium, yttrium and rare earths.