摘要
为探讨改性碳纳米管(CNTs)对砷的吸附特性,采用化学修饰对CNTs进行了改性。将CNTs先后进行氧化和酰胺化处理,并与聚苯胺反应,得到酰胺化/氧化碳纳米管-聚苯胺(NMCNTs-PANI),利用SEM观察、比表面积测定、含氧含氮官能团和分子结构分析对改性前后CNTs进行了表征;研究了NMCNTs-PANI在不同反应体系对As(Ⅲ)的吸附效果。结果表明:NMCNTs-PANI总孔容和平均孔径均有所增加;表面含氧含氮基团增加;初始pH对吸附量影响较显著;共存阴离子对吸附量影响可忽略不计;吸附过程符合准一级动力学和准二级动力学方程,证实该过程主要以化学吸附为主;吸附等温线符合Langmuir模型。NMCNTs-PANI通过表面吸附-化学诱导作用可较好地去除水中As(Ⅲ),是一种优良的含砷污染水的吸附剂。
To promote the As(Ⅲ) adsorption capacity of carbon nanotubes(CNTs), the modification of CNTs was conducted in this study. Firstly, CNTs were modified with oxidation and amidation, followed by reaction with polyaniline to obtain amidated/oxidized carbon nanotube-polyaniline(NMCNTs-PANI). Both the modified and pristine carbon nanotubes were observed by scanning electron microscope to compare their morphological differences. Their specific surface, functional groups and molecular structure were also determined. The adsorption behavior of As(Ⅲ) on NMCNTs-PANI was further studied. The results show that the total pore volume and average pore size of NMCNTs-PANI increased, as well as the surface oxygen and nitrogencontaining groups. The initial pH had significant effects on the adsorption capacity, while the coexisting anions had a negligible effect on As(Ⅲ) adsorption. The kinetic data fitted well with the pseudo-first-order and pseudosecond-order kinetic model, which demonstrated that chemical adsorption was the main mechanism. The adsorption isotherms of NMCNTs-PANI fitted well with the Langmuir model. The good performance on As(Ⅲ)removal by NMCNTs-PANI was completed through surface adsorption-chemical induction actions. The high As(Ⅲ) removal efficiency of the NMCNTs-PANI makes it to be an excellent adsorbent for arsenic-contaminated water treatment.
作者
叶智新
任刚
YE Zhixin;REN Gang(School of Environment,Jinan University,Guangzhou 511486,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2019年第12期2798-2807,共10页
Chinese Journal of Environmental Engineering
基金
广东省科技计划项目(2013B020800005、2015A020217005)
广东省水利科技创新项目(2016-30)
广州市民生科技攻关计划项目(201803030043).
