摘要
采用电化学实验研究了在氰化浸金过程中常见矿物高岭石对金溶解速率及对溶液中金的吸附效果的影响。结果表明,高岭石的存在会使金的溶解速率加快,随着高岭石粒度逐渐降低金的溶解速率提高,且高岭石对溶液中金的吸附率增加。氰化浸出实验结果表明,高岭石存在时金的浸出率由93.21%降低到91.76%,采用柠檬酸三钠、过氧化镁和十二烷基硫酸钠助浸时,金浸出率升高至94.42%。能谱分析(EDS)发现浸出物中高岭石表面有金元素存在,表明高岭石会吸附溶液中的金。红外光谱分析和密度泛函理论计算表明,高岭石与金发生化学吸附作用,氢原子为高岭石的活性位点,C_(6)H_(5)O_(7)^(3-)-会优先吸附于高岭石(001)表面,加入助浸剂可降低高岭石与金的吸附强度,提高金的浸出率。
The effect of kaolinite on gold dissolution rate and adsorption of gold in cyanide leaching was studied by electrochemical experiments.The results show that the presence of kaolinite accelerates the dissolution rate of gold,and with the decrease of kaolinite particle size,the dissolution rate of gold increases,and the adsorption rate of gold on kaolinite increases.In the cyanide leaching experiments,gold leached rate decreased from 93.21%to 91.76%in the presence of kaolinite but increased to 94.42%with the aid of trisodium citrate,magnesium peroxide and sodium dodecyl sulfate.EDS reveals kaolinite is present on the surface of the extract,which indicats that kaolinite can adsorb gold in the solution.Infrared spectrum analysis and density functional theory calculation demonstrate that the chemical adsorption of gold on kaolinite takes place and hydrogen is the active site of kaolinite.C_(6)H_(5)O_(7)^(3-)is preferentially adsorbed on the surface of kaolinite(001).The leaching aid can reduce the adsorption intensity of gold on kaolinite,improving the gold leached rate.
作者
余鑫
代淑娟
韩佳宏
苑林松
陈瑜
李鹏程
YU Xin;DAI Shujuan;HAN Jiahong;YUAN Linsong;CHEN Yu;LI Pengcheng(School of Mining Engineering,Liaoning University of Science and Technology,Anshan 114051,Liaoning,China;Chaoyang Teachers College,Chaoyang 122000,Liaoning,China)
出处
《贵金属》
CAS
北大核心
2023年第1期26-33,共8页
Precious Metals
基金
国家自然科学基金项目(No.51574146)。
关键词
氰化浸金
高岭石
助浸剂
密度泛函理论
量子模拟
电化学
cyanide leaching gold
kaolinite
leaching aid
density functional theory
quantum simulation
electro-chemistry
