Study on the treatment of wastewater containing low concentration As(Ⅲ) by Fe-Mn modified biochar
Biochar was prepared from corn straw and modified by alkali precipitation,and its adsorption mechanism and properties on As(Ⅲ) in water were analyzed through static and dynamic experiments.The results showed that the static adsorption was consistent with the pseudo-second-order kinetic model and Freundlich isothermal adsorption model.The adsorp-tion process of As(Ⅲ) was mainly chemical adsorption of heterogeneous multilayer.The maximum static adsorption capacity of Fe-Mn modified biochar(FMBC)was 20.63 mg/g.FMBC had a wide range of suitable pH for adsorption of As(Ⅲ),but PO3-4 and SiO2-3 of the co-existing substances had great influence on the adsorption effect.The influent flow rate and As(Ⅲ) concentration could affect the effective bed volume of dynamic adsorption.Both Thomas model and Yoon-Nelson model had a good fitting effect on the dynamic adsorp-tion curve.When the concentration of As(Ⅲ) was 200 μg/L and the flow rate was 9 mL/min,the maximum dynamic adsorption capacity of FMBC was 1.41 mg/g.This study can provide necessary data support for the application of FMBC in treating wastewater containing As(Ⅲ).
万方数据
维普
