カルボン酸による水酸化物の溶解

抄録

The paper describes an improved process for the recovery, purification and concentration of metal values from process streams. The process employes carboxylic acids capable of extracting metal values from their hydroxides which is suspended in aquous solutions. Tertiary carboxylic acids, Versatic 9 and 911, are shown to act as a useful extractant for Cu, Zn, Ni and the other metals. When a slurry of a metal hydroxide is brought into contact with a solution of the carboxylic acid in kerosene the hydroxide readily dissolves and the metal carboxylate is formed in the organic phase. Carboxylic acid concentration affects the dissolution of the hydroxide. In the case of 0.22 M Versatic 911, a limited amount of copper hydroxide which is precipitated from 0.05M copper sulphate solution, can be dissolved. In applying them in mineral processing, a metal is expected to be extracted by, single stage solvent extraction after the complete neutralization of feed solution with alkali and the decantation. The raffinate which contains a small amount of the metal is recycled to the first neutralization step. Since distribution ratio increases in proportion to the phase ratio A/O, the process is an ideal way of concentrating a solution without evaporating water.