摘要
The adsorption behaviors and mechanisms of gold from thiosulfate solution on strong-base anion exchange resin were systematically investigated.The comparison experiment of adsorption ability and selectivity for gold showed that gel Amberlite IRA-400 resin with Type Ⅰ quaternary ammonium functional group had better adsorption performance.The increases of resin dosage,ammonia concentration and solution pH were favorable to gold adsorption,whereas the rises of cupric and thiosulfate concentrations were disadvantageous to gold loading.Microscopic characterization results indicated that gold was adsorbed in the form of [Au(S_(2)O_(3))_(2)]^(3–) complex anion by exchanging with the counter ion Cl^(–) in the functional group of the resin.Density functional theory calculation result manifested that gold adsorption was mainly depended on the hydrogen bond and van der Waals force generated between O atom in [Au(S_(2)O_(3))_(2)]^(3–) and H atom in the quaternary ammonium functional group of the resin.
系统研究了硫代硫酸盐溶液中的金在强碱阴离子交换树脂上的吸附行为和机理。对金的吸附能力和选择性对比实验表明,具有Ⅰ型季铵官能团的凝胶型Amberlite IRA-400树脂具有更好的吸附性能。树脂用量、氨浓度和溶液pH的增加有利于金的吸附,而二价铜离子和硫代硫酸盐浓度的增加不利于金的吸附。微观表征结果表明,金是通过与树脂官能团上的反离子Cl^(–)交换,以[Au(S_(2)O_(3))_(2)]^(3–)配合物阴离子的形式被吸附。密度泛函理论计算结果表明,树脂对金的吸附主要依靠[Au(S_(2)O_(3))_(2)]^(3–)中的O原子与树脂的季铵基官能团上的H原子之间形成的氢键和范德华力来实现。
基金
the financial support from the Natural Science Foundation of Hunan Province, China (No. 2023JJ40723)
China Postdoctoral Science Foundation (No. 2022M723549)
the National Natural Science Foundation of China (Nos. 52174271, 51504293)。
作者简介
Corresponding author:Bin XU,Tel:+86-15084933770,E-mail:xubincsu@csu.edu.cn。
