Comparison of Counter Current Extraction Process of Pr & Nd Separation using Cyanex 572 and PC88A

This study designed a counter current extraction process for comparing the separation efficiencies that are obtained using Cyanex 572 and PC88A for the elements in a Pr and Nd mixed solution. This process involves multiple extraction and scrubbing processes using a mixer settler. The process parameters are calculated using an equation proposed by Xu Guangxian. The separation factor for the extraction and scrubbing process was 0.09 and 0.08 higher when using Cyanex 572 compared to the experimental values obtained using PC88A. The optimized extraction factors such as the stage numbers, feeding solution flow rate, organic phase flow rate, and scrubbing solution flow rate were calculated using the optimal extraction ratio equation. In order to derive optimum extraction conditions, the target purity and recovery ratio of Nd was set to 99.9% and 99% respectively. When using Cyanex 572 for the counter current extraction process, the total number of extraction and scrubbing stages decreased by 11 in comparison with PC88A. A comparison between the extraction, scrubbing stages, and other parameters indicate that Cyanex 572 is preferable over PC88A from the viewpoint of economic efficiency. Key words: counter current extraction, cyanex 572, PC88A, rare earth metal, separation factor