Isothermal adsorption characteristics and applications of Cu , Zn , and Pb in typical soil of Shanxi

QIN Jun-mei 1,LIU Fen-wu 1,ZHOU Jun 2,Bu Yu-shan 1*(1.College of Resource and Environment,Shanxi Agricultural University,Taigu 030801,China;2.Faculty of Biotechnology and Pharmaceutical Engineering,Nanjing University of Technology,Nanjing 211816,China)

calcareous clay soil;calcareous sandy soil;alkaline bentonite;isothermal adsorption;heavy metals

It was significant to find cheap and efficient adsorption materials to remove heavy metals from wastewater.In this study,the isothermal adsorption efficiencies of Cu,Zn,and Pb by calcareous clay soil,calcareous sandy soil,and alkaline bentonite were investigated through shake flask experiments.In addition,the removal efficiencies of Cu,Zn,and Pb from sewage treatment plant wastewater were studied by the above three adsorption material in the subsequent fixed bed adsorption process.Results showed that the isothermal adsorption characteristics of Cu,Zn,and Pb by calcareous clay soil,calcareous sandy soil,and alkaline bentonite was obviously correlated with Freundlich equation.The heavy metals adsorption forces of the calcareous clay soil,calcareous sandy soil,and alkaline bentonite were Zn> Cu>Pb,Cu>Zn>Pb,and Cu>Zn>Pb,respectively,while the heavy metals adsorption capacity of the calcareous clay soil,calcareous sandy soil,and alkaline bentonite were Cu>Zn>Pb,Pb>Cu>Zn,and Cu>Pb>Zn.Meanwhile,further fixed bed adsorption experiments revealed that the removal efficiency of Cu,Zn,and Pb from wastewater by calcareous clay soil adsorption were 79.9%,97.7%,and 73.4%,and the removal efficiency of Cu,Zn,and Pb by the alkaline bentonite adsorption were also reached to 70.3%,90.6%,and 90.6%,respectively.The results obtained from this study were helpful in choose of adsorbent to remove the heavy metals from wastewater.