【摘要】 以松木屑与海藻酸钠为碳源,FeCl₃为交联剂与赋磁剂,制备了磁性生物炭球（MB）。利用海藻酸钠与FeCl₃之间发生的交联反应实现了同步成型与赋磁。利用BET、SEM、XRD、FT-IR、VSM等分析手段对MB进行了表征,证明了MB具有较大的比表面积和良好的孔隙结构,其表面成功负载了Fe₃O₄并具有良好的磁性。低温热解制备的MB表面含有丰富的氧官能团,易与Pb（Ⅱ）络合。在初始pH为6、MB添加量为10%、吸附时间为24 h的条件下,300℃热解制备的MB的最佳去除率和吸附量分别为67.53%和3.11 mg/g。吸附符合准二级动力学方程,以化学吸附为主。MB在吸附土壤中的Pb（Ⅱ）后可通过外加磁场实现分离回收,回收率可达95%以上。对MB循环再生5次后,MB对Pb（Ⅱ）仍能保持初始吸附量的71%。更多还原

【Abstract】 Magnetic biochar（MB） spheres were prepared using the pine sawdust and sodium alginate as carbon sources,FeCl₃ as the cross-linking agent and magnetization agent. Synchronous molding and magnetization were realized by the cross-linking reaction between sodium alginate and FeCl₃. The MB was characterized by analysis methods such as BET,SEM,XRD,FT-IR and VSM. The results proved that MB had large specific surface area and good pore structure. MB showed good magnetism because its surface was successfully loaded with Fe₃ O₄. The surface of MB prepared by low-temperature pyrolysis was rich in oxygen functional groups,so it was easy to complex with Pb（Ⅱ）.When initial p H = 6,MB addition = 10% and adsorption time = 24 h,the optimal removal rate and adsorption capacity of MB prepared by 300 ℃ pyrolysis were 67.53% and 3.11 mg/g,respectively. The adsorption process fitted the quasi second order kinetics equation,and was mainly chemical adsorption. After adsorbing Pb（Ⅱ）in soil,MB could be separated and recovered by external magnetic field,and the recovery rate was more than 95%. After 5 times of regeneration,MB could still maintain 71% of the initial adsorption of Pb（Ⅱ）.更多还原