Cl^-对碳纳米管/过一硫酸盐体系降解金橙G的影响  

Effect of chloride ions on degradation of Orange G with peroxymonosulfate activated by carbon nanotubes

作　　者：张黎明[1] 陈家斌[1] 房聪[1] 周露[1] 胡金梅[1] 郝尚斌 李文卫[2] 王忠明[1] 黄天寅[1] ZHANG Li-ming;CHEN Jia-bin;FANG Cong;ZHOU Lu;HU Jin-mei;HAO Shang-bin;LI Wen-wei;WANG Zhong-ming;HUANG Tian-yin(School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China;School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China)

机构地区：[1]苏州科技大学环境科学与工程学院,江苏苏州215009 [2]中国科学技术大学化学与材料科学学院,安徽合肥230026

出　　处：《中国环境科学》2016年第12期3591-3600,共10页China Environmental Science

基　　金：国家自然科学基金项目(51478283);苏州科技学院学术学位研究生科研创新计划项目(SKCX15_026)

摘　　要：采用碳纳米管(CNT)活化过一硫酸盐(PMS)的方法产生自由基,研究氯离子(Cl^-)对CNT/PMS体系氧化降解金橙G(OG)的影响.发现Cl-对CNT/PMS体系氧化降解OG的过程具有双重影响,低浓度Cl-会抑制OG的脱色,高浓度Cl-会促进OG的脱色;无CNT存在时Cl-会直接与PMS作用使OG脱色.研究了CNT/PMS/Cl-体系降解OG的主要影响因素(PMS浓度、反应温度、OG初始浓度、Cl-浓度、初始p H)和反应机制,结果表明PMS浓度为1.6mmol/L、反应温度为25℃时、OG初始浓度为0.8mmol/L、Cl-浓度为50mmol/L和p H=7的条件下,25min内OG脱色率可达到100%,反应体系的活化能为88.45k J/mol;随着初始p H升高,OG脱色率先减后升,降解OG的活性物质为SO_4^-·和HOCl.对OG降解过程的矿化率分析表明,CNT存在条件下OG的矿化率要比无CNT存在时要好;然后通过紫外可见扫描光谱扫描和GC-MS分析,发现OG分子中偶氮键及萘环结构被破坏后,生成了其他小分子物质.The radical was formed by the carbon nanotube(CNT)activation of peroxymonosulfate(PMS).Effect ofchloride ion(Cl-)on degradation of Orange G(OG)by CNT/PMS system were investigated.Cl-had a dual effect on OGdecolorization in the CNT/PMS system.Low dosage of Cl-could inhibit OG decolorization,whereas high dosage couldpromote its decolorization.Meanwhile,Cl-could directly react with PMS alone to decolorize OG.In the CNT/PMS/Cl-system,effect of various factors were explored,including PMS dosage,reaction temperature,initial concentration of OG,Cl-concentration,and initial pH,and the degradation mechanism was further proposed.The results indicated that100%decolorization of OG was observed after25min when1.6mmol/L of PMS,0.08mmol/L of OG,50mmol/L of Cl-werepresent at25℃.The activation energy of reaction system was determined to be88.45kJ/mol.With the increasing initialpH,OG decolorization was decreased first and then gradually increased.Both of SO4-?and HOCl were found to beresponsible for OG degradation.The mineralization rate during the degradation of OG were analyzed,and highermineralization rate was observed when CNT was present in the system.From the analysis of UV-vis spectra and GC-MS,the azo band and naphthaline ring of OG were destroyed to generate other small intermediates.

关 键 词：碳纳米管 Cl- 过一硫酸盐 金橙G 脱色率 

分 类 号：X703[环境科学与工程—环境工程]