Abstract
The effect of temperature on the solvent extraction of Cu, Ni, Co and Mn with Versatic acid 911 diluted in benzene was studied. Extraction temperature was varied between 10 and 60°C, and the results obtained are summarized as follows:
(1) The equilibrium distribution ratio of metal is raised with the temperature. (2) The change in the composition of extracted species was not observed in the extraction of Cu and Ni in this temperature range, while the extracted species of Co was of dimeric form above 40°C and Mn ion was oxidized in the aqueous phase above the same temperature. (3) The extraction reaction of these metals is endothermic, and the heat of extraction of Cu, Ni and Co were 10.8, 14.5 and 18.9 kcal/mol, respectively. (4) A linear relationship in the form of pH0.5=a+bT−1 (a, b: constant) was observed in the extraction of these metals.
