Processes of approximation and restoration of a degraded organic phase of metal oxime extraction agent and metal extraction in a metal extraction circuit

摘要

"PROCESS OF REOXIMATION AND RESTORATION OF A DEGRADED ORGANIC PHASE OF METAL EXTRACTION AND METAL EXTRACTION IN A METAL EXTRACTION CIRCUIT". A process for purifying a degraded organic phase of metal oxime extraction agent from a metal extraction circuit in which a degraded organic phase of metal oxime extraction agent comprised of a metal oxime extraction agent, and aldehyde or ketone, which degrades in a water-immiscible hydrocarbon solvent, is brought back together, thus restoring the organic phase of oxime extraction agent for later extraction in the metal extraction circuit. Optionally, the degraded organic phase can be purified by distillation before approximation. Distillation is performed on a mirrored film evaporator at temperatures above 180 ° C to about 250 ° C at a pressure of about 66.7 Pa or less than about 1,333 Pa and the rapprochement is performed with hydroxylamine in the presence of a weak organic carboxylic acid as a phase transfer catalyst and in the presence of an alkali metal or alkaline earth metal carbonate or hydroxide, preferably sodium carbonate.