[Objective]The abilities of dead Sargassum sp.biomass as a biosorbent for removing and recovering Cd2+ and Ni2+ ions from aqueous solutions were studied in batch experiments. Adsorption velocity,kinetics,metal selection and absorbent regeneration were also investigated in this work.[Methods]On the basis of single factor analysis,the effects of adsorption parame-ters,such as pH,initial concentration and counter ions,on uptake capacities of Cd2+ and Ni2+were evaluated.The adsorption data were fitted by the pseudo-first and pseudo-second order ki-netics.[Results]The optimal adsorption factors for Cd2+ were pH of 4.5,initial concentration of 500mg/L,counter ions of NO-3 ,and the optimal adsorption factors for Ni2+ were pH of 3.0,in-itial concentration of 900mg/L,counter ion of Cl-.The equilibrium time for Cd2+ and Ni2+ was 50min and 25min,respectively.Both adsorptions of Cd2+ and Ni2+ onto Sargassum sp.were in good agreement with the pseudo-second order kinetic model,and the correlation coefficients (R2)were above 0.99.The order of selectivityfor different heavy metal ions in a mixed solutionwas Pb2+>Ni2+>Cd2+>Mn2+.The desorptionrates of Cd2+ and Ni2+ reached 99% in theory byusing 1.0mol/L HCl as a desorption reagent.[Conclusion]These results illuminated that deadSargassum sp.is an excellent biosorbent for re-moving and recovery heavy metals from aqueous solution,and it has a broad perspectives in industrial application in the future.%【目的】以马尾藻粉为生物吸附剂，研究其在静态实验中对Cd2＋和 Ni2＋的吸附及脱附能力，并对吸附速度、动力学、重金属选择性和吸附剂再生等问题进行探讨。【方法】采用单因素法分析 pH 值、初始浓度、平衡离子类型等条件因素对重金属吸附容量的影响，采用准一级和准二级动力学模型对 Cd2＋、Ni2＋的吸附数据进行拟合。【结果】Cd2＋的最佳吸附条件为pH值4．5、初始浓度500mg/L、平衡离子为NO3-，Ni2＋的最佳吸附条件为pH值3.0、初始浓度900mg/L、平衡离子为Cl-；Cd2＋、Ni2＋的吸附平衡到达时间分别为50min和25min；准二级动力学模型对吸附数据的拟合效果更好，相关系数（R2）均大于0．99；对混合溶液中不同重金属的选择性吸附顺序为Pb2＋＞Ni2＋＞Cd2＋＞Mn2＋；1．0mol/L HCl 对 Cd2＋、Ni2＋的理论洗脱率均可达到99％。【结论】马尾藻粉对Cd2＋和 Ni2＋的吸附容量大，吸附条件温和，重金属脱附率高，是一种性能良好的生物吸附剂。
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