摘要
通过试验研究了硫化银在[Bmim]HSO4-Fe2（SO4）3-硫脲体系中的浸出动力学。试验考察了硫脲浓度、搅拌强度、浸出温度对银浸出率的影响,研究结果表明,硫脲浓度对银浸出率影响较大,银的浸出率随硫脲浓度增大呈直线增长趋势,当浓度达到0.16mol/L后,增长趋势减缓。提高温度能显著提高银浸出速率和浸出率,当温度从298 K升至328 K时,浸出率由61.21%提高至82.91%,所需浸出时间也由18 h缩短至15 h;搅拌强度对银浸出率有一定影响,但影响有限。浸出动力学研究表明,采用外扩散控制动力学方程和内扩散控制动力学方程分别进行拟合,表明银浸出过程在298~328 K温度范围内符合＂未反应核收缩＂模型,浸出过程主要受内扩散步骤控制,浸出过程的表观活化能为27.99 kJ/mol。
Research was conducted on leaching kinetics of silver sulfur in [ Bmim ] HSO4-Fe2 （ SO4 ） 3-thiourea system. Effects of thiourea concentration, stirring speed and leaching temperature on the leaching rate of silver were investigated. Results showed that the leaching rate of silver has been greatly influenced by the thiourea concentration, presenting a linear increasing trend with an increase in the concentration. However, such growth trend slows down after the concentration reaches 0. 16 mol/L. Besides, a higher temperature can remarkably improve the leaching speed and leaching rate of silver. Tests showed that the leaching rate was improved from 61.21% to 82.91% and leaching time required was shorten from 18 hrs to 15 hrs as the temperature rose from 298 K to 328 K. Stirring speed has also some extent of influence on the silver leaching rate, but very limited. In the research of the leaching kinetics, after being fitted with the kinetic equation of external diffusion controlling and kinetic equation of inner diffusion controlling, respectively, it is found that silver-leaching process at the temperature ranging from 298 K to 328 K, conforming with ＂unreacted shrinking core＂ model is predominantly controlled by the inner diffusion step, with an apparent activation energy at 27.99 kJ/mol.
出处
《矿冶工程》
CAS
CSCD
北大核心
2014年第3期76-79,共4页
Mining and Metallurgical Engineering
基金
国家自然科学基金资助项目(51174103
51104077)
江西省科技支撑计划项目(2011BBG70002-2)
江西省教育厅科技计划资助项目(GJJ11480)
