三仲辛胺萃取铼的热力学研究

Thermodynamics of Solvent Extraction of Re(VII) with T-sec-octylamine

用三仲辛胺(下称R3N)为萃取剂,以正庚烷为稀释剂萃取铼的热力学研究.在NH4ReO4+H2SO4+R3N+n-C7H16+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Na2SO4为支持电解质,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,同时计算了萃取反应的其他热力学量.

This paper reported the thermodynamics of extraction of Re( VII) with the extractant t-sec-octyl-amine (R3N) in the H2SO4 system. The equilibrium molalities of ReO4- in the extraction R3N(org) + H + (aq) + ReO4- (aq) = R3NHReO4(org) were measured at ionic strengths from 0.1 to 2.0 mol · kg-1 in the a-queous phase containing Na2SO4 as the supporting electrolyte and at constant initial molality of extractant in the, organic phase at temperatures from 278. 15 to 303. 15 K. The standard extraction constants K at various temperatures were obtained. Thermodynamic quantities for the extraction process were calculated.