采用水为浸出剂,浸出铅冶炼过程中产生的高砷烟尘。通过p H、液固比、浸出时间和浸出温度等浸出条件变化对砷浸出率的影响,用扫描电镜(SEM)、X射线衍射分析(XRD)及能谱分析仪(EDS)表征原料及浸出渣的结构和形貌,揭示烟尘中砷的浸出规律和动力学行为。结果表明:液固比和浸出温度对砷的浸出率影响最大,浸出过程符合JohnsonMehl-Avrami(JMA)模型,浸出过程受扩散控制,其动力学方程为-ln(1-α)=9.4×106exp[-503 80/(RT)]t0.310 6,浸出过程的频率因子A=9.4×106,表观活化能Ea=50.38 k J/mol。
The objective of this article was exploring the leaching kinetics of arsenic contained in high arsenic dust. High arsenic dust from lead smelter was processed by leaching with water. The effects of p H,liquid-solid ratio,reaction time and temperature on the rate of arsenic leaching were studied,and SEM,XRD and EDS were employed to character the structure of raw material and leach residue for investigating the kinetics of arsenic leached from dust. It was demonstrated that the liquid-solid ratio and leaching temperature has the greatest influence on the leaching rate,and that the leaching kinetics of arsenic is correspondent with the Johnson-Mehl-Avrami( JMA) model. The diffusion is the bottle-neck limiting leaching rate of arsenic within the selected temperature range,and the kinetic equation is- ln( 1- α) = 9. 4 × 106exp[- 50 380 /( RT) ]t0. 3106 with the leaching process frequency factor of 9. 4 × 106 and the apparent activation energy of 50. 38 k J / mol.
Journal of Sichuan University (Engineering Science Edition)
high arsenic dust
hazards solid waste