In the present work, a novel α-aminophosphonate extractant（Cextrant 230） was synthesized for the extraction and recovery of cerium and thorium from sulphate medium. The introduction of amine group into the phosphat...In the present work, a novel α-aminophosphonate extractant（Cextrant 230） was synthesized for the extraction and recovery of cerium and thorium from sulphate medium. The introduction of amine group into the phosphate molecule would enhance the extraction of Ce（Ⅳ） and Th（Ⅳ）. The effects of extractant concentration, H2SO4 concentration and temperature on the metal extraction were investigated in detail. It was found that the extraction of Ce（Ⅳ）, Th（Ⅳ） and REs（La, Gd, Yb） in sulphate medium decreased in the following order： Ce（Ⅳ）〉Th（Ⅳ）〉REs（Ⅲ）. A solvent extraction process to extract and recover cerium and thorium from bastnasite leaching was proposed, in which the purities of cerium and thorium products reached 99.9% and 99% with yield of 92% and 98%, respectively.展开更多
A calixarene derivative, 5,11,17,23-tetra（diethoxyphosphoryl）-25,26,27,28-tetraacetoxycalix[4]arene （L）, was studied for the extraction and separation of thorium and rare earths in nitrate medium. Thorium was extr...A calixarene derivative, 5,11,17,23-tetra（diethoxyphosphoryl）-25,26,27,28-tetraacetoxycalix[4]arene （L）, was studied for the extraction and separation of thorium and rare earths in nitrate medium. Thorium was extracted into the organic phase by a complex of Th（NO3）4·L with the logarithm of the equilibrium constant of 2.77. Thermodynamic functions, AH, AG and AS were calculated to be -2.49, -15.55 kJ/mol and 44.53 J/（mol·K）, respectively. The results indicated that this calixarene derivative might be used to separate thorium from rare earths and the separation factors were larger than 26. However, the salting-out agents affected the separation.展开更多
基金Project supported by National Basic Research Program of China(973 program,2012CBA01206)the National Natural Science Foundation of China(21521092,51222404)the Strategic Priority Research Program of CAS(XDA02030100)
文摘In the present work, a novel α-aminophosphonate extractant（Cextrant 230） was synthesized for the extraction and recovery of cerium and thorium from sulphate medium. The introduction of amine group into the phosphate molecule would enhance the extraction of Ce（Ⅳ） and Th（Ⅳ）. The effects of extractant concentration, H2SO4 concentration and temperature on the metal extraction were investigated in detail. It was found that the extraction of Ce（Ⅳ）, Th（Ⅳ） and REs（La, Gd, Yb） in sulphate medium decreased in the following order： Ce（Ⅳ）〉Th（Ⅳ）〉REs（Ⅲ）. A solvent extraction process to extract and recover cerium and thorium from bastnasite leaching was proposed, in which the purities of cerium and thorium products reached 99.9% and 99% with yield of 92% and 98%, respectively.
基金Project supported by National Basic Research Program of China (2012CBA01206)National Natural Science Foundation of China (51074148,51222404,91026024)
文摘A calixarene derivative, 5,11,17,23-tetra（diethoxyphosphoryl）-25,26,27,28-tetraacetoxycalix[4]arene （L）, was studied for the extraction and separation of thorium and rare earths in nitrate medium. Thorium was extracted into the organic phase by a complex of Th（NO3）4·L with the logarithm of the equilibrium constant of 2.77. Thermodynamic functions, AH, AG and AS were calculated to be -2.49, -15.55 kJ/mol and 44.53 J/（mol·K）, respectively. The results indicated that this calixarene derivative might be used to separate thorium from rare earths and the separation factors were larger than 26. However, the salting-out agents affected the separation.
