【作者】 付念新； 田中斡也；

【Author】 Fu Nianxin, Tanaka Mikiya(School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China;Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8569, Japan)

【机构】 东北大学材料与冶金学院； 产业技术综合研究所环境管理技术研究部门；

【摘要】 在非理想条件下,研究了溶于Shellsol D70中的2-乙基己基膦酸单(2-乙基己基)酯(P507)分别对硝酸和盐酸溶液中钇和铕的萃取平衡,建立能预测平衡分配比的化学基模型。结果表明,在低酸度区萃取主要按阳离子交换反应进行,在高酸度区溶剂化萃取反应则变得明显。此外,模型还涉及稀土和NO3-或Cl-的络合反应、萃取剂对HNO3的竞争萃取以及对(?)的非理想性的修正。采取非线性最小二乘法确定了萃取平衡常数。对稀土单元体系,在初始浓度较宽范围内(矿酸0．05-3 kmol·m-3及萃取剂0．25-1 kmol·m-3),模型能以良好精度预测实验数据。更多还原

【Abstract】 The extraction equilibria of Y (Ⅲ) and Eu (Ⅲ) in the nitric acid and hydrochloric acid solutions with 2-ethylhexyl phosphonic acid mono-2-ethylhe-xyl ester (P507) dissolved in Shellsol D70 were studied under non-ideal conditions to develop a chemically-based model enabling the prediction of the equilibrium distribution ratio. As a result, the cation exchange reaction is predominant in the low acidity region, and the salvation extraction becomes appreciable in the high acidity region. In addition, the model also involves the coraplexation of RE with NO3- and Cl-, the competing extraction of HNO3 with the extractant and the correction to the non-ideality of (HR)2 . The extraction equilibrium constants were determined by the nonlinear least squares method. The proposed model can predict the experimental data with good accuracy for the single metal systems over wide feed concentration ranges of mineral acid (0.05 to 3 kmol·m-3) and the extractant (0.25 to 1 kmol·m-3).更多还原