Separation of yttrium from rare earth using hollow fiber-supported liquid membrane: factorial design analysis

The selective separation of yttrium ions from other rare earth elements using a hollow fiber-supported liquid membrane was performed. The extractant was Cyanex272 and the stripping solution was nitric acid. Yttrium was extracted preferentially in comparison to other rare earth elements. The pH and flow rate of the feed solution, as well as the concentration of Cyanex272, were regarded as factors in the experiments. A 2(3) factorial design was used to determine the significant factor, their interaction, and optimized condition. Linear regression model and surface response were applied to predict the percentages of extraction of yttrium at different values of significant factors. The validity of linear regression model was evaluated through a comparison with experimental data, with good agreement achieved.