含锌废渣及贫杂锌矿的碱浸动力学研究

研究了含锌废渣及贫杂锌矿在碱浸过程中的动力学。结果表明,含锌废渣(ZnO)在碱溶液中的浸出过程符合关系式1-(1-η)13=kt,表观活化能为49.22 kJ/mol,说明浸出过程受化学控制;贫杂锌矿(ZnCO3)在碱溶液中的浸出过程可分为两段,在开始段时间内,1-(2/3)η-(1-η)2/3与浸出时间呈直线关系,活化能为19.95 kJ/mol;而在6 min以后则是1-(1-η)13与浸出时间呈直线关系,活化能为46.54 kJ/mol。说明在开始时间段内是受内扩散控制,而随后的浸出过程是受化学反应控制。

Kinetic Study on Alkaline Leaching of Waste and Lean Ores Bearing Zinc

The leaching reaction kinetics of waste bearing zinc and smithsonite in alkaline solution were studied.For waste bearing zinc,plot of 1-(1-η)13 versus leaching time giving linear relationship indicated that the velocity of leaching was controlled by the chemical reaction step,the apparent activation energy was obtained to be 49.22 kJ/mol from an Arrhenius plot.For smithsonite,during the early stage of leaching reaction,1-(2/3)η-(1-η)2/3 was linear with leaching time,with the apparent activation energy of 19.95 kJ/mol;while in the later stage,1-(1-η)13 was linear with leaching time,with the apparent activation energy of 46.54 kJ/mol.Thus,it indicated that the leaching mechanism of smithsonite changes from inner diffusion control to chemical reaction control.