用Fe₃O₄对谷壳生物炭进行改性得到磁性生物炭。利用SEM、XRD对磁性生物炭进行表征，并通过响应面优化和共吸附实验探究该生物炭在共吸附系统中对As³⁺和Cd²⁺的吸附性能。结果表明，在pH为5.0、镉（砷）初始质量浓度分别为10 mg/L、吸附剂质量浓度为1 g/L时，镉和砷去除率达到最大。在共吸附实验中，As³⁺和Cd²⁺共存时，Cd²⁺质量浓度大于20 mg/L时会抑制生物炭对As³⁺的吸附，10 mg/L As³⁺与生物炭达到平衡后可以使50 mg/L Cd²⁺的吸附量由17.44 mg/g增加到31.91 mg/g，说明砷和镉之间存在协同作用，该协同作用是由于镉、砷与四氧化三铁形成了B型三元表面配合物，增大了镉的吸附量。

Fe₃O₄ is used to modify husk biochar to obtain magnetic biochar.The obtained biochar is characterized by SEM and XRD.Response surface optimization and co-adsorption experiments are conducted to investigate the adsorption performance of the biochar to As³⁺ and Cd²⁺ in the co-adsorption system.The results show that the removal rates of the biochar to cadmium and arsenic respectively reach the highest when pH is 5.0,initial mass concentration of As³⁺ or Cd²⁺ is 10 mg·L^-1 and adsorbent dosage is 1 g·L^-1.In As³⁺/Cd²⁺co-adsorption experiment,when the mass concentration of Cd²⁺ ix more than 20 mg·L^-1,it can inhibit the adsorption of As³⁺ by the biochar,the adsorption capacity of the biochar to 50 mg·L^-1 Cd²⁺ increases from 17.44 mg·g^-1 to 31.91 mg·g^-1 after the pre-equilibrium between 10 mg·L^-1 As³⁺ and the biochar,indicating there is a synergistic adsorption effect between arsenic and cadmium.This synergistic effect is due to the formation of B-type ternary surface complexes of Cd,As and Fe₃O₄,which can increase the adsorption capacity of cadmium.

李景心(1995-),女,硕士研究生,研究方向为废水处理新技术与新材料,1494606918@qq.com