Abstract: A magnetic biosorbent was synthesized with Rhizopus oryzae powder, FeSO4 and Fe3O4. With the anionic azo dye Congo Red (CR) solution as the target pollutant, the effects of m-RBps dosage, pH value and initial CR concentration were studied, and the adsorption kinetics and thermodynamics discussed. The results indicated that the decolorization rate of CR increased with rising of the adsorbent dosage, and the effect of initial CR concentration on its adsorption capacity was remarkable. When the pH value, CR concentration and m-RBps dosage were 7.0, 20 mg/L and 1.0 g/L, respectively, the effect of adsorbent was the best, and over 98.68% of CR was removed. The adsorption of CR on m-RBps followed the Langmuir isotherm model. The adsorption procedure met pseudo-second-order kinetic equation, and the intra-particle diffusion was the rate-controlling step. Furthermore, the magnetic biosorbent could be easily recycled with an external magnetic field, thus simplifying the further processing of adsorption of anionic azo dye.

Key words: Rhizopus oryzae, adsorption, magnetic biosorbent, Congo Red, kinetics

摘要： 以产富马酸米根霉菌体粉末、FeSO4和FeCl3为原料，制备了米根霉磁性生物吸附剂，考察了吸附剂投加量、pH值、刚果红浓度、吸附时间及吸附动力学等对阴离子偶氮染料刚果红的吸附影响. 结果表明，刚果红去除率随吸附剂投加量增加而提高，增大溶液初始浓度能有效提高吸附量，当吸附剂为1.0 g/L, pH=7.0时，吸附效果最佳，刚果红浓度为20 mg/L去除率达98.68%以上. 米根霉磁性吸附剂对刚果红的吸附等温线符合Langmuir模型，吸附过程符合拟二级动力学方程，内扩散为主要控速步骤. 吸附剂有较强磁性，在外加磁场下能快速实现固液分离和回收，可简化刚果红偶氮染料吸附的后续处理.

关键词: 米根霉, 吸附, 磁性生物吸附剂, 刚果红, 动力学