硝酸处理的碳纳米管吸附水溶液中汞离子的研究  

Adsorption of Mercury(Ⅱ) in Aqueous Solution with Carbon Nanotubes Treated by Nitric Acid

作　　者：葛海峰[1] 刘宝春[1] 曹德峰[1] 

机构地区：[1]南京工业大学理学院,江苏南京210009

出　　处：《环境科学与技术》2010年第3期158-161,共4页Environmental Science & Technology

摘　　要：碳纳米管是一种具有独特结构和优异性能的纳米材料。该文研究了硝酸处理的碳纳米管作为吸附剂吸附水溶液中的汞离子的吸附特性,考察了溶液pH值、吸附时间、溶液浓度以及吸附剂的量等因素对吸附行为的影响。实验结果表明:在pH值为2～5的范围内,碳纳米管对汞离子的吸附量随着pH值的增大而增大,并在pH为5时(对汞离子的吸附量)达到了最大值,在pH大于5时,pH值对吸附效果影响不大。碳纳米管吸附汞离子的量随着吸附时间的增加而增大,且在60min内达到了吸附平衡,当Hg2+浓度为20mg/L时吸附量为16.63mg/g。通过对Langmuir和Freundlich方程对吸附等温线的拟合比较,Langmuir方程更适合描述吸附特性。随着吸附剂量增加,吸附效率上升。研究结果表明,硝酸处理的碳纳米管是一种有效的水溶液中汞离子的吸附剂。Carbon nanotubes treated by nitric acid were employed as absorbent to study the adsorption characteristics for Hg^2＋ in aqueous solution. Experimental results showed that the adsorption capacity reached the maximum when pH was 5 and the adsorption attained equilibrium in 60min. The adsorption capacity was 16.63mg/g for 20mg/L Hg^2＋ solution, Adsorption efficiency of Hg^2＋ ion increased with increasing of carbon nanotubes dosage. By comparison of the adsorption isotherm of Langmuir and Freundlich equation, Langmuir equation was more suitable to describe the adsorption characteristics.

关 键 词：碳纳米管 吸附 汞离子 吸附量 

分 类 号：X703.1[环境科学与工程—环境工程]