N-Fe/CNT对Pb(Ⅱ)去除的热力学与动力学研究  

Thermodynamic and kinetic study on removal of Pb(Ⅱ)by carbon nanotubes-green nano zero valence iron(nZVI)composites

作　　者：刘清[1] 杨涛[1] 滑熠龙 何小燕 招国栋 LIU Qing;YANG Tao;HUA Yi-long;HE Xiao-yan;ZHAO Guo-dong(Hunan Key Laboratory of Pollution Control and Resource Reuse,University of South China,Hengyang 421001,China;School of Environmental Protection and Safety Engineering,University of South China,Hengyang 421001,China;Zhuzhou City Water Investment Group Co.,Ltd.,Zhuzhou 412000,China)

机构地区：[1]南华大学,污染控制与资源化技术湖南省重点实验室,湖南衡阳421001 [2]南华大学资源环境与安全工程学院,湖南衡阳421001 [3]株洲市水务投资集团有限公司,湖南株洲412000

出　　处：《应用化工》2020年第8期2029-2034,2055,共7页Applied Chemical Industry

基　　金：国家自然科学基金青年基金资助项目(51304122);南华大学“青年英才”人才支持计划资助项目(南华政发[2014]49号)。

摘　　要：使用新鲜向日葵提取液、硫酸亚铁、多壁碳纳米管(MWCNT)等3种原料制备碳纳米管-绿色纳米铁复合材料(N-Fe/CNT),研究pH、不同浓度阴阳离子及反应时间对N-Fe/CNT吸附Pb(Ⅱ)的影响。结果表明,当pH=6时,吸附效果最佳为94.7%;Ca^2+、Mg^2+、SO^2-4和CO^2-3对实验均有一定影响,主要原因是溶液中有沉淀生成,影响反应。等温吸附方程Freundlich能更好描述N-Fe/CNT对Pb(Ⅱ)的吸附过程,吸附容量Qmax=15.02 mg/g;热力学研究表明,焓变ΔH<0,熵变ΔS>0,吉布斯自由能ΔG<0,可得N-Fe/CNT对Pb(Ⅱ)的吸附是放热、自发且以物理吸附为主的吸附过程。Elovich动力学模型更适合描述N-Fe/CNT对Pb(Ⅱ)的吸附,吸附以表面吸附为主。Using fresh sunflower extract,ferrous sulfate(FeSO4·7H 2 O)and multi-walled carbon nanotube(MWCNT)N-Fe/CNT to prepare carbon nanotubes-green iron nanoparticles composites(N-Fe/CNT).Study pH,different concentration of anionic and cationic and the reaction time on N-Fe/CNT adsorption Pb(Ⅱ)effect.The results showed that when pH=6,the adsorption effect is best,94.7%;Ca^2+,Mg^2+,SO^2-4 and CO^2-3 all have certain effects on the experimental effects,mainly due to the formation of precipitation in solution,which affects the reaction.Experiments using quasi 1,compound 2 and Elovich kinetics model for calculation and analysis,draw Elovich kinetics model is more suitable for describing N-Fe/CNT adsorption of Pb(Ⅱ)adsorption is given priority to with surface adsorption;Using Langmuir and Freundlich isothermal adsorption equation can better describe N-Fe/CNT adsorption process of Pb(Ⅱ),N-Fe/CNT is higher adsorption capacity for Pb(Ⅱ)(Q max=15.02 mg/g);Thermodynamic studies showed that enthalpy change<0,entropy change>0,gibbs free energy<0,the adsorption of Pb(Ⅱ)by N-Fe/CNT was exothermy,spontaneous and mainly physical adsorption process.

关 键 词：N-Fe/CNT Pb(Ⅱ) 热力学 动力学 等温线 

分 类 号：TQ013.1[化学工程] TQ013.2