Applicability of Isotherm Model in Liquid-Liquid Extraction
GAO Jia-Jun1, CAI Yuan1, YIN Xia1, JIANG Xing-Mao1**, LI Chun-Xi2**
1. School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430205, China;
2. College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
Abstract Distribution of equilibrium concentration of solute between two immiscible phases is a core issue of liquid-liquid extraction. For most of theoretical and experimental courses in chemistry or chemical engineering, the extraction systems that showed the linear distribution were selected as teaching examples. However, the systems showing the non-linear distribution rarely occurred in teaching. This was because the current model applied in the systems mentioned above was quite complex. In the teaching research, we found that the common isotherm model can well describe the non-linear distribution of many systems, and that the distribution coefficient can be expressed by determined functional relationship as well. Further, we also found that the model applicability of extraction systems highly related to interaction mechanism among solute, solvent and extractant thereof. Above all, applying the isotherm model in the liquid-liquid extraction can solve the complexity issue of the current model, expand the teaching contents, help students better understand the extraction mechanism, and train them in scientific thinking.
GAO Jia-Jun, CAI Yuan, YIN Xia, JIANG Xing-Mao, LI Chun-Xi. Applicability of Isotherm Model in Liquid-Liquid Extraction[J]. Chinese Journal of Chemical Education, 2021, 42(4): 90-95.