摘要
以实验室制备的羟基化锌(ZnOOH)为催化剂,考察了其催化臭氧化去除水中痕量对氯硝基苯(pCNB)的效能,通过研究自由基抑制试剂叔丁醇对催化效果的影响,推断了催化反应机理,并研究了催化性能的影响因素.结果表明,ZnOOH具有较强的催化臭氧化去除pCNB能力.本实验条件下,蒸馏水中反应20 min时,催化臭氧化比单独臭氧化对pCNB的去除率提高了51.3个百分点;催化过程遵循自由基反应机理,催化剂表面结合的羟基基团有利于催化反应;pCNB的去除效果随催化剂投量的增加而更佳,催化剂重复使用3次后,催化效果基本没有变化,水中的重碳酸盐以及缓冲溶液中的磷酸盐可以明显降低催化活性,中性条件下,催化作用最佳.
Zinc hydroxide prepared in laboratory was used as catalyst in catalytic ozonation of trace p-chloronitrobenzene （pCNB） in water. The catalytic mechanism was deduced through the effect of radical inhibitor t-BuOH on the reaction. Furthermore, affecting factors of catalytic activity were investigated. Results show that zinc hydroxide has excellent property of catalytic ozonation. Compared to ozonation alone, the catalytic removal rate of pCNB dissolved in distilled water increases by 51.3 percents at reacting time of 20 min. The catalysis, which is influenced by density of hydroxyl groups combined on the surface of hydroxide, follows a hydroxyl radical reaction pathway. The removal gets better with increasing dosage of catalyst. Zinc hydroxide was used for 3 times without obvious changes of pCNB removal rate. Bicarbonate in water and phosphate in buffer solution could greatly depress its catalytic activity. The optimal catalysis is achieved at solution pH = 7.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2007年第11期2550-2556,共7页
Environmental Science
基金
新世纪优秀人才支持计划项目(NCET-04-0321)
国家自然科学基金项目(50578052)
关键词
催化臭氧化
对氯硝基苯
羟基化锌
羟基自由基
catalytic ozonation
p-chloronitrobenzene
zinc hydroxide
hydroxyl radical
作者简介
陈忠林（1967-），男，博士，教授，博士生导师，主要研究方向为饮用水除污染理论与技术，E-mail：zhonglinchen@hit．edu．cn．zhonglinchen@263．net
