McCABE-THIELE ANALYSIS FOR EVALUATION OF EXTRACTION SEPARATION OF Co (II) AND Ni (II)

摘要

Industrial solvent extraction for the separation and recovery of metal ions is often carried out during the countercurrent multistage process. The determination of the operating conditions is performed by McCabe-Thiele analysis, which obtains the equilibrium extraction isotherms from extraction experiments. In such an analysis, it is possible to analyze the extraction condition of metal ions. In the case of a mixed solution of Co (II) and Ni (II), however, the analysis is very complicated. This is because, under the conditions in which the extraction of Co (II) takes place, the stripping of Ni (II) happens at the same time. When considering the separation of metal ions in a multicomponent system, it is optimal to establish an analytical method to provide important guidelines for the actual operation. In this study, the conditions in which Co (II) is extracted and Ni (II) is stripped are considered. The extraction behavior of Co (II) and the stripping behavior of Ni (II) can be estimated from the extraction isotherms. On the basis of the estimated results of each metal ion, the separation performance of each can be evaluated using the purity as an indicator. Through experiments that vary the phase ratio and stage number, the extraction and stripping behavior of the respective metal ions can be reasonably estimated.