摘要
利用壳聚糖改性磁性Fe_3O_4以提高其对重金属Pb(Ⅱ)和Cd(Ⅱ)的吸附性能,考察了改性前后磁性Fe_3O_4对Pb(Ⅱ)、Cd(Ⅱ)的吸附等温线及吸附动力学过程。结果表明,经壳聚糖改性后,壳聚糖-磁性Fe_3O_4比表面积大幅增加,由原来的76.12m2/g增加到142.67m2/g;壳聚糖-磁性Fe_3O_4对Pb(Ⅱ)、Cd(Ⅱ)的吸附性能优于磁性Fe_3O_4;当pH为2.0~7.0时,提高pH有助于促进两种磁性材料对Pb(Ⅱ)和Cd(Ⅱ)的吸附量;两种磁性材料对Pb(Ⅱ)和Cd(Ⅱ)的吸附符合准二级动力学模型,吸附过程属于吸热过程;重复吸附—脱附循环再生5次后,壳聚糖-磁性Fe_3O_4对Pb(Ⅱ)、Cd(Ⅱ)的去除率仍在80%以上,磁性Fe_3O_4对Pb(Ⅱ)、Cd(Ⅱ)的去除率在75%以上,两种磁性材料再生性能较好。
In this paper,the chitosan was employed to modify the surface structure of synthesized magnetic Fe3O4 in order to enhance its adsorption capacity towards heavy metals Pb（Ⅱ）and Cd（Ⅱ）.The adsorption isotherms and adsorption kinetics of magnetic Fe3O4 and chitosan-magnetic Fe3O4 for Pb（Ⅱ）and Cd（Ⅱ）was investigated and compared.The results showed that the surface area of magnetic Fe3O4 increased from 76.12m2/g to 142.67m2/g after chitosan modification.The adsorption properties of chitosan-magnetic Fe3O4 on Pb（Ⅱ）and Cd（Ⅱ）were better than those of magnetic Fe3O4.When pH ranged 2.0-7.0,increasing pH would promote the adsorption quantity of two magnetic materials on Pb（Ⅱ）and Cd（Ⅱ）.The adsorption of Pb（Ⅱ）and Cd（Ⅱ）by two magnetic materials conformed to the quasi two order kinetic model,and the adsorption process belonged to endothermic process.After regeneration for 5times,Pb（Ⅱ）and Cd（Ⅱ）removal rate of chitosan-magnetic Fe3O4 was still more than 80%,and that of magnetic Fe3O4 was more than 75%,showing the better regeneration performance of two magnetic materials.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2017年第7期746-751,共6页
Environmental Pollution & Control
基金
安徽省高校自然科学研究重点项目(No.KJ2016A622)
