金属溶剂萃取热力学研究——6.(TI_2SO_4+Na_2SO_4+D_2EHMTPA+n-C_8H_(18)+水)

Studies on the Thermodynamics of Solvent Extraction of Metals 6.{Tl_2SO_4+Na_2SO_4+D_2 EHMTPA+n-C_8H_(18)+Water}

在278.15—298.15K 和离子强度为0.1—2.0mol/kg 范围内,在较高的浓度和酸度的萃取体系{TI_2SO_4+Na_2SO_4+D_2EHMTPA+n-C_8H_(18)+水}中,测定了萃取反应:TI_(aq)^++H_2A_(2(org))(TIHA_(2(org))+H_((aq))^+的 TI^+在平衡水相的浓度,根据 Pitzer 电解质溶液理论,估算了平衡水相的有效离子强度,用外推法和多项式拟合法确定了萃取反应的热力学平衡常数,计算并讨论了这个萃取反应的其它热力学量.

The equilibrinm molalities Tl^+ of extraction reaction: Tl^+(aq)+H_2A_2(org)=TlHA_2(org)+H^+(aq) in {Tl_2SO_4+Na_2SO_4+D_2EHMTPA+n-C_8H_(18)+water} were measured at ionic strength from 0.1 to 2.0 mol·kg^(-1) containing Na_2SO_4 as supporting electrolyte in aqueous phase and at constant molality extractant at temperatures from 278.15 to 303.15 K in organic phase.The standard extraction constants K^0 at various temperatures were obtained by methods proposed in our previous paper.Thermo dynamic quantities for the extraction process were calculated.