Minimum Amount of Extracting Solvent of a Separation of Two Rare Earth Components

A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASIR), are deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed.

Share and Cite:

Cheng, F. , Wu, S. , Liu, Y. , Wang, S. , Zhang, B. , Liao, C. and Yan, C. (2014) Minimum Amount of Extracting Solvent of a Separation of Two Rare Earth Components. Advances in Materials Physics and Chemistry, 4, 275-283. doi: 10.4236/ampc.2014.412030.

Conflicts of Interest

The authors declare no conflicts of interest.

 [1] Xu, G.X. (1978) Theory of Counter Current Extraction I. Equations of Optimization and Their Applications. Acta Scientiarum Naturalium Universitatis Pekinensis, 1, 51-66. (In Chinese) [2] Li, B.G., Xu, X.Y. and Xu, G.X. (1980) Theory of Counter Current Extraction III: A Mathematical Model for the Dynamic Equilibrium of Counter Current Extraction. Acta Scientiarum Naturalium Universitatis Pekinensis, 1, 66-84. (In Chinese) [3] Xu, G.X., Li, B.G. and Yian, C.H. (1985) Theory of Countercurrent Extraction and Its Applications in Rare Earth Extraction Industry. In: New Frontiers in Rare Earth Science and Applications, Science Press, Beijing, 429-437. [4] Li, B.G., Li, J.R., Yian, C.H., Qiao, S.P. and Xu, G.X. (1985) Theory of Countercurrent Extraction VII. Dynamic Equilibrium in Three-Component System. In: New Frontiers in Rare Earth Science and Applications, Science Press, Beijing, 438-441. [5] Xu, G.X. (2005) Theory of Countercurrent Extraction. In: Rare Earths, Metallurgical Industry Press, Beijing, 612-727. (In Chinese) [6] Yan, C.H. (1988) One-Step Scale-Up of Rare Earth Extraction Separation Process. Doctoral Dissertation, Peking University, Beijing. (In Chinese) [7] Gao, S. (1988) Theory and Industrial Applications of Five-Component Countercurrent Extraction System. Doctoral Dissertation, Peking University, Beijing. (In Chinese) [8] Xu, G.X., Gao, S., Li, B.G., Yan, C.H. and Huang, C.H. (1993) New Progresses on Extraction Separation Processes of Rare Earths. Journal of the Chinese Rare Earth Society, 11, 193-198. (In Chinese) [9] Wang, Z.H. (1995) Design Calculation for Multi-Component Rare Earth Separation by Solvent Extraction: Equivalent Composition-Equivalent Separation Factor Method. Chinese Rare Earths, 16, 10-14. (In Chinese) [10] Liao, C.S. (1996) Extraction Separation of Heavy Rare Earths. Doctoral Dissertation, Peking University, Beijing. (In Chinese) [11] Huang, X.W., Long, Z.Q., Li, H.W., Ying, W.W., Zhang, G.C. and Xue, X.X. (2005) Development of Rare Earth Hydrometallurgy Technology in China. Journal of Rare Earths, 23, 1-4. [12] Han, Q.Y., Yang, J.H., Li, J.F. and Bai, W. (2011) New Three-Group Progress for Separation of the Rare Earth Mineral with Middle Y and Rich Eu. Chinese Rare Earths, 32, 72-77. (In Chinese) [13] Hao, J.N., Zhang, L.P., Yian, C.H., Li, B.G. and Xu, G.X. (1985) Experimental Verification of Countercurrent Extraction Theory Separation of La and Ce by HEH(EHP) in New Frontiers in Rare Earth Science and Applications. Science Press, Beijing, 442-445. [14] Wu, S., Liao, C.S., Jia, J.T. and Yan, C.H. (2004) Static Design for Multiple Components and Multiple Outlets Rare Earth Countercurrent Extraction [I]: Algorithm of Static Design. Journal of the Chinese Rare Earth Society, 22, 17-21. (In Chinese) [15] Wu, S., Liao, C.S., Jia, J.T. and Yan, C.H. (2004) Static Design for Multi-Component and Multi-Outlet Rare Earth Countercurrent Extraction [II]: Static Design and Its Verification. Journal of the Chinese Rare Earth Society, 22, 171-176. (In Chinese) [16] Yan, C.H., Jia, J.T., Liao, C.S., Wu, S. and Xu, G.X. (2006) Rare Earth Separation in China. Tsinghua Science and Technology, 11, 241-247.http://dx.doi.org/10.1016/S1007-0214(06)70183-3 [17] Feng, Z.Y., Huang, X.W., Liu, H.J., Wang, M., Long, Z.Q., Yu, Y. and Wang, C.M. (2012) Study on Preparation and Application of Novel Saponification Agent for Organic Phase of Rare Earths Extraction. Journal of Rare Earths, 30, 903-908. http://dx.doi.org/10.1016/S1002-0721(12)60152-5 [18] Han, Q.Y. (2013) Technical and Economical Evaluation on Separation of Light Rare Earth. Journal of the Chinese Rare Earth Society, 31, 399-404. (In Chinese) [19] Liao, C.S., Wu, S., Cheng, F.X., Wang, S.L., Liu, Y., Zhang, B. and Yan, C.H. (2013) Clean Separation Technologies of Rare Earth Resources in China. Journal of Rare Earths, 31, 331-336. http://dx.doi.org/10.1016/S1002-0721(12)60281-6 [20] Cheng, F.X., Wu, S., Liao, C.S. and Yan, C.H. (2013) Adjacent Stage Impurity Ratio in Rare Earth Countercurrent Extraction Process. Journal of Rare Earths, 31, 169-173. http://dx.doi.org/10.1016/S1002-0721(12)60253-1 [21] Cheng, F.X., Wu, S., Liu, Y., Wang, S.L., Zhang, B., Liao, C.S. and Yan, C.H. (2014) Minimum Amount of Extracting Solvent for AB/BC Countercurrent Separation Using Aqueous Feed. Separation and Purification Technology, 131, 8-13. http://dx.doi.org/10.1016/j.seppur.2014.04.031 [22] Cheng, F.X., Wu, S., Zhang, B., Liu, Y., Wang, S.L., Liao, C.S. and Yan, C.H. (2014) Minimum Amount of Extracting Solvent of AB/BC Countercurrent Extraction Separation Using Organic Feed. Journal of Rare Earths, 32, 439-444. http://dx.doi.org/10.1016/S1002-0721(14)60091-0