Recovery of indium from aq. acid lixiviating soln. - by extraction using solvent containing tri:alkyl phosphine oxide(s)

摘要

Indium is extracted from aq. acid lixiviating soln. by contacting the soln. with an extraction solvent made up of dialkyl-phosphonic acid and a tert. phosphine oxide chosen from (1) a mixt. contg. at least 4 different compounds having the same general formula, RR1R2PO, in which R, R1, R2 are hydrocarbon radicals, differently or identically saturated, with 6-16 C-atoms, and at least 2 cpds. are asymmetric tert. phosphine oxides contg. at least one group R, R1 and R2 which is different to the other gps.; or (2) a mixt. of ramified tert. phosphine oxides chosen from R3(R4)2PO and (R4)3PO, where R3 and R4 are hydrocarbon radicals saturated with 6-16C atoms, R3 is not ramified and R4 has at least 2 ramifications per hydrocarbon radical; or (3) a combination of (1) and (2). ADVANTAGE - The recovery of small quantities of indium from lixiviation acids based on sulphate is efficient.