金属氧化物在ChCl-urea低共熔溶剂中的溶解行为及其热力学  

Dissolution Behavior and Thermodynamic of Metallic Oxides in ChCl-Urea Deep Eutectic Solvent

作　　者：陈晓 徐存英[1,2] 栗健茹 华一新 张启波[1,2] 郑敏 Chen Xiao;Xu Cunying;Li Jianru;Hua Yixin;Zhang Qibo;Zheng Min(Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;State Key Laboratory of Complex Nonferrous Metal Resources Cleaning Utilization,Kunming 650093,China)

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093 [2]复杂有色金属资源清洁利用国家重点实验室,云南昆明650093

出　　处：《稀有金属》2024年第12期1713-1720,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金地区基金项目(51764027,51866003);云南省基础研究计划项目(2019FB071)资助。

摘　　要：在323~363 K的温度范围内,测定了ZnO,Cu_(2)O,CuO等一系列含锌烟尘中常见金属氧化物在氯化胆碱-尿素(ChCl-urea)低共熔溶剂中的溶解度,发现ZnO和Cu_(2)O溶解度较大,分别介于0.1906%~37.2683%和0.0220%~3.1470%之间,远高于CuO,Ni_(2)O_(3),Co_(2)O_(3)和Fe_(3)O_(4)的溶解度(0.0045%~0.1803%,0.0070%~0.2574%,0.0034%~0.1174%和0.0007%~0.0045%)。当温度从323 K升高到363 K,ZnO和Cu_(2)O在ChCl-urea中的溶解度迅速增加,分别达到195和146倍,而CuO,Ni_(2)O_(3),Co_(2)O_(3)和Fe_(3)O_(4)的溶解度仅分别增加了40,36,34和66倍。通过回归分析,得到了溶解度随温度变化的经验方程。建立了ChCl-urea溶剂与固体金属氧化物的两相平衡,并通过相平衡规律,分别计算了不同金属氧化物在ChCl-urea低温熔盐中的活度系数、过剩溶解吉布斯自由能、过剩焓以及过剩熵。随着温度的升高,各个金属氧化物在ChCl-urea中的活度系数逐渐减小。此外,在ChCl-urea低共熔溶剂中ZnO活度系数远小于其他金属氧化物活度系数,表明低共熔溶剂对ZnO的吸引力大于对其他金属氧化物的吸引力。同时,ZnO溶解在ChCl-urea低共熔溶剂的过剩熵也较小,约为79 J·mol^(-1),表明溶解有ZnO的低共熔溶剂溶液体系更接近于规则溶液。Deep eutectic solvents(DESs),which are prepared from quaternary ammonium salts mixed with hydrogen bond donors(HBD)such as amides,alcohols and carboxylic acids,have been developed as a promising solvent for organic synthesis,extraction and separation of metal and metal electrodeposition due to their excellent physicochemical properties.Additionally,they can selectively dissolve valuable metal oxide such as zinc oxide and cuprous oxide,but are unable to dissolve gangue ingredients including ferric oxide,calcium oxide and aluminium oxide,which offers an effective way for the recovery of zinc from zinc-containing secondary resources such as steelmaking dust,zinc slag,zinc smelting fume,etc.But so far,there are very few studies on the dissolution of metal oxides in deep eutectic solvents,and the relevant data are very scarce.Thus,it is of great interest to measure the solubility of metal oxides in deep eutectic solvents systematically and to study their thermodynamics of dissolution.Here,the solubility of main metal oxides that present in steel-making dust,including ZnO,Cu_(2)O,CuO,Ni_(2)O_(3),Co_(2)O_(3)and Fe_(3)O_(4),in ChCl-urea DES was systematically measured by chemical method in the temperature range of 323~363 K.It was found that the solubility of these metal oxides in ChCl-urea DES varied widely.The solubilities of ZnO and Cu_(2)O in ChCl-urea ranged from 0.1906%to 37.2683%and from 0.0220%to 3.1470%respectively,which were much higher than those of CuO(0.0045%~0.1803%),Ni_(2)O_(3)(0.0070%~0.2574%),Co_(2)O_(3)(0.0034%~0.1174%)and Fe_(3)O_(4)(0.007%~0.0465%)in ChCl-urea DES.This demonstrated that ZnO and Cu_(2)O had good solubility in ChCl-urea DES,while the rest of metal oxides were slightly soluble or insoluble in ChCl-urea DES,which was conducive to the selective dissolution of zinc from steelmaking dust.With an increase of temperature from 323 to 363 K,the solubility of all metal oxides in ChCl-urea DES increased rapidly,but the degree of increase was different.The solubilities of ZnO and Cu_(2)O increased

关 键 词：低共熔溶剂 氯化胆碱-尿素 金属氧化物 溶解度 热力学 

分 类 号：TF803.2[冶金工程—有色金属冶金] TG832[金属学及工艺—公差测量技术]