Adsorption Characteristics of Cd2+ Ions in Aqueous Solution on Modified Straw Biochar

Rice straw and corn were selected as raw materials to prepare biocharby anoxic carbonization the biochar was loaded on surface with FeCl3, MnCl2 Fe(NO3)3 & KMnO4, respectively, then two types of six modified prepared. FT-IR, SEM, XRD used characterize analyze physical chemical properties biochar. The adsorption kinetics isothermal tests Cd2+ ions in aqueous solution carried out. results showed that biochars attached more active sites group, especially iron-manganese-modified (FMBC1, FMBC2). kinetic process eight kinds all conformed quasi-second-order equation, chemisorption maybe dominated process. test by FeCl3-modified (FBC1, FBC2) KMnO4-modified FMBC2) conforms Freundlich model, MnCl2-modified (MBC1, MBC2) Langmuir model. Compared other biochar, KF value rice (FMBC1) largest, reached 18.602 L·mg−1, its 1/n smallest, it 0.474, indicating effect FMBC1 best.