摘要 |
<p>Metal values, particularly copper values, are extracted from aqueous solutions containing halide or pseudohalide anion using 6, 7 substituted triazolopyrimidine wherein the 6-substituent is a group -CO-OR1 where R1 is a hydrocarbyl group containing from 1 to 35 carbon atoms, preferably an alkyl group and wherein the 7-substituent (R2) is hydrogen or a hydrocarbyl group containing from 1 to 35 atoms wherein R1 and R2 taken together contain a total of from 5 to 35 saturated carbon atoms.</p> |