摘要
以硫酸为浸镍剂,从某表面处理工业园电镀废水处理污泥中提取镍,通过单因素优化试验探讨了影响镍浸出效率的主要因素,如污泥粒径、硫酸质量分数、固液比、浸出时间、浸出温度等,并对硫酸浸镍过程的动力学机理进行了研究。结果表明:当污泥粒径为147μm、硫酸质量分数为20%和固液比为1∶7(g∶m L)时,在常温条件下反应60 min,污泥中镍的浸出率可达96%以上;硫酸浸出镍的过程符合收缩未反应核模型,其动力学方程为1-23η-(1-η)23=KDt,浸出反应级数为1,浸出活化能Ea为3.127 k J/mol,指前因子A为0.011 7,反应速率常数为K=0.0117e-3.127RT,根据该模型可知,硫酸浸出镍的决定步骤为固体膜扩散。
In this paper,we have been engaged in a study of the leaching rate of nickel from sludge treating for electroplating sewage in a surface water treatment industrial park.To achieve the research purpose,we have first of all made the sludge dried,ground and then leached in the sulfuric acid solution at different concentrations.The leaching processing and recycling of nickel isolation is done,it can be said that the purification and recycling purpose has been achieved.Actually,all the treatment has been done under the strict control,including the solid-liquid ratio,leaching time,choice of sludge particle size and temperature.And,then,lixivium can be successfully separated from the residue with a suction filter.The results of the singular factor experiment show that over 96% nickel can be taken off the sludge（147μm） in a period of 60 min treatment by 20% sulfuric acid（solidto-liquid ratio 1 g：7 m L） at 20 ℃.The total dynamic process of treatment of the nickel-leaching process has been done by using the unreactable core contracting model.As a matter of fact,the necessary condition of the solid-liquid ratio in the processing separation stands for 1：7.With the sludge particle size being 147μm and the leaching temperature being 20 ℃,we have successfully changed the sulfuric acid concentration and the reaction time.The results of our experiment of the leaching and separation indicate that the rate of nickel leaching in this study can mainly be controlled by the solid membrane diffusion rate,whose reaction equation is equal to 1-23η-（1-η）23 = KDt,with the reaction order being 1.Under the condition of 20% of the sulfuric acid content without changing the solid-liquid ratio and the sludge particle size,we have successfully worked out the leaching activation energy at an efficiency of 3.127 k J/mol with the pre-exponential factor being 0.011 7 just by changing the reaction temperature and time.The experimental results can be summarized in the following aspects：the activation energy is low,which implie
出处
《安全与环境学报》
CAS
CSCD
北大核心
2016年第3期242-246,共5页
Journal of Safety and Environment
关键词
环境工程学
电镀污泥
镍
硫酸
浸出过程
动力学
environmental engineering
electroplating sludge
nickel
sulfuric acid
leaching process
kinetics
