1954年Cunninghame等首先发现用HTTA和TBP混合萃取镨和钕时有协同效应产生,因此人们对协同效应进行了大量的研究,发现了一些新的协同萃取体系。但把协同萃取体系实际应用于工业上稀土分离的却较少。主要原因是协同效应的结果往往使分离因素降低。Manning曾指出,协同效应不利于分离。我 In 1954, Cunninghame et al. First discovered that synergistic effects were produced when praseodymium and neodymium were mixed by HTTA and TBP. Therefore, a great deal of researches on synergistic effects were found and some new synergistic extraction systems were discovered. However, the practical application of synergistic extraction system for industrial rare earth separation is less. The main reason is that the result of the synergistic effect tends to reduce the separation factor. Manning pointed out that synergies are not conducive to separation. I