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当前,治理可溶性重金属污染是环境保护的迫切任务.以氧化石墨烯(GO)和铁盐为前驱体,一步合成了部分还原氧化石墨烯-Fe_3O_4复合材料(rGO-Fe_3O_4),探索其作为Cd(II)高效吸附剂的潜力.同时,采用多种手段表征吸附剂结构和特性,重点研究了吸附剂对Cd(Ⅱ)的吸附特性和动力学.结果表明,在吸附剂中,纳米Fe_3O_4颗粒均匀地锚在石墨烯片层之间,避免了片层团聚,赋予其优良的吸附性能.在中性溶液中,使用rGO-Fe_3O_4(500 mg·L~(-1))吸附200.09 mg·L~(-1)Cd(II),5 min即可达到吸附平衡,吸附率和吸附量分别为90.88%和363.99 mg·g~(-1).另外,磁分离回收吸附剂仅需10 s,且循环吸附性良好.进一步研究显示,复合材料对Cd(II)的吸附为吸热、自发的化学吸附,过程受化学吸附和液膜扩散控制.
At present, the treatment of soluble heavy metal pollution is an urgent task for environmental protection.Optimized by partial reduction of graphene oxide-Fe 3 O 4 composite (rGO-Fe 3 O 4) with graphene oxide (GO) and iron salt as precursors, II) Potentials of high efficiency sorbent.At the same time, the structures and properties of sorbent were characterized by various means, and the adsorption properties and kinetics of sorbent on Cd (Ⅱ) were studied emphatically.The results showed that in the sorbent, nano-sized Fe_3O_4 particles were uniform In the neutral solution, rGO-Fe 3 O 4 (500 mg · L -1) was used to adsorb 200.09 mg · L ~ (-1) of graphene, (-1) Cd (II) for 5 min, the adsorption rate and adsorption capacity were 90.88% and 363.99 mg · g -1, respectively.In addition, it took only 10 s to recover the adsorbent by magnetic separation The results show that the adsorption of Cd (II) on the composite is endothermic and spontaneous chemisorption, and the process is controlled by chemical adsorption and liquid film diffusion.