N263和TBP为协同流动载体的液膜体系分离钐(Ⅲ)和钆(Ⅲ)的研究

研究了N263和TBP为协同载体的液膜体系分离钐和钆的行为.考察了膜相添加剂、内水相反萃剂、外水相盐析剂和膜相中载体浓度对传质分离的影响.当用TBP作为膜相添加剂时,N263能很好地溶解在煤油中.N263-TBP-LMA-1-煤油和NH₄NO₃协同流动载体液膜体系在迁移稀土离子时表现出"倒序"特性,与单纯的N263体系相比,该体系对钐、钆具有较高的选择性.

Studies of Separation of Sm3+ and Gd3+ by Liquid Membranes System Containing TBP and N263 Co-extraction Mobile Carrier

The separation of Sm³⁺ and Gd³⁺ by liquid membranes system containing TAP and N263 co-extraction mobile carrier was studied. The effect of several factors on transport of Sm³⁺ and Gd³⁺ was examined. N263 can be dissolved in kerosene when TBP was used as oil adjusting agents. So kerosene may take the place of some aromatic diluents. On the other hand, a co-extraction effect was found between N263 and TBP in membrane process. Instead of using dilute HNO₃ as stripping agent, dilute NH₄NO₃ was used to be an internal aqueous phase in the experiment. The stripping result of dilute NH₄NO₃ for Sm³⁺ and Gd³⁺ was similar to that of dilute HNO₃ as their concentrations were all in 0. 01～0.5 mol/L. When the membrane system of N263-TBP LMA-1-kerosene (oil phase) and NH₄NO₃ (internal aqueous phase) was applied, the transport rate decreased with the increase of atomic number of rare earth, and the system selectivity for Sm³⁺ and Gd³⁺ is better than N263 system.