N235萃取铼的热力学研究

Thermodynamics of Solvent Extraction of Rhenium With N235

以N235为萃取剂,正庚烷为稀释剂,在盐酸体系中研究萃取铼的热力学.在N235＋（NH4）ReO4＋n-C7H16＋HCl＋H2O体系中,在温度278.15-303.15 K和离子强度0.1-2.0 mol.kg-1范围内,以NH4Cl为支持电解质,在HCl体系中测定了萃取平衡水相中ReO4-浓度和pH值.计算了萃取反应的标准平衡常数K0,并利用EXCEL得到经验公式logK0=15.7445—745.501/T-0.0253T,同时计算了萃取反应的其他热力学量,指出了该萃取过程的推动力.

This paper reported the thermodynamics of extracting Re with the extractant of N235 in the HCl system.The equilibrium molalities of ReO 4-were measured at ionic strengths from 0.1 to 2.0 mol·kg-1 in the aqueous phase and at constant initial molality of extractant in the organic phase at temperatures from 278.15 to 303.15K.The standard equilibrium constant K 0 at various temperatures were obtained by EXCEL,and the thermodynamic quantities for the extraction process were calculated.