摘要
利用机械球磨的方法可以提高天然黄铁矿的活性,通过XRD和TEM对机械球磨后黄铁矿粉末的表面形态和物理性质进行表征。通过批实验的方法探讨在不同的pH,不同的球磨黄铁矿用量,不同的反应时间和温度的条件下黄铁矿对Cr^(6+),Cd^(2+)和Pb^(2+)的去除效果。研究结果表明,金属离子的吸收受到pH的影响,随着pH的升高,3种金属离子的吸附趋势出现了很大的不同。并且在分析pH对反应效果的影响时,需要考虑金属生成沉淀时的pH。同时,随着反应时间和温度的增加,3种金属离子的吸收量都有不同程度的升高。通过实验比较,球磨黄铁矿对Cr^(6+),Cd^(2+)和Pb^(2+)的去除能力大小为Pb^(2+)>Cr^(6+)>Cd^(2+)。纳米级黄铁矿与Cr^(6+),Cd^(2+)和Pb^(2+)的反应过程符合准二级动力学方程。
The use of mechanical ball milling to prepare pyrite nanoparticles can improve the activity of natural pyrite. Physical properties and surface morphologies of the pyrite nanoparticles after ball milling were monitored by X-ray diffraction（ XRD） and transmission electron microscopy（ TEM）. The removal effects of Cr^（6＋）,Cd^（2＋）,and Pb^（2＋）under conditions of different pH values,different dosages of the milled pyrite,different reaction times,and different temperatures were investigated by batch experiments. The results showed that metal ion adsorption was affected by the pH and with increasing pH,the adsorptions of Cr^（6＋）,Cd^（2＋）,and Pb^（2＋）were different. Furthermore,the precipitation pH of metal ions should also be considered. With increasing reaction time and temperature,the uptakes of Cr^（6＋）,Cd^（2＋）and Pb^（2＋）increased. The Cr^（6＋）,Cd^（2＋）,and Pb^（2＋）adsorption capacities decrease in the order of Pb^（2＋） Cr^（6＋） Cd^（2＋）. The dynamic adsorption data of Cr^（6＋）,Cd^（2＋）,and Pb^（2＋）on nano-sized pyrites were well described by a pseudo second-order kinetic equation.
出处
《环境工程学报》
CAS
CSCD
北大核心
2016年第12期7103-7108,共6页
Chinese Journal of Environmental Engineering
关键词
纳米级黄铁矿
重金属
吸附
动力学
nanoscale pyrite
heavy metal
adsorption
kinetics
