研究或检测方法
皮运正,王建龙.对氯苯甲酸用于测量OH#方法探讨2.误差分析[J].环境科学学报,2005,25(11):1560-1564
对氯苯甲酸用于测量OH#方法探讨2.误差分析
- Investigation of para-chlorobenzoic acid used for the detection of OH# radicals 2. Error analysis
- 基金项目:国家自然科学基金(No.50325824);中国博士后科学基金
- 皮运正
- 清华大学核能与新能源研究院环境技术研究室 北京 100084
- 王建龙
- 清华大学核能与新能源研究院环境技术研究室 北京 100084
- 摘要:对氯苯甲酸用于测量臭氧氧化过程中产生的OH#浓度时会产生误差.为了研究误差的大小,进行了臭氧的间歇实验,以测量臭氧分解速率常数k.通过对比乙二酸、甲苯和腐殖酸溶液中投加对氯苯甲酸前后k值的变化,判断投加的对氯苯甲酸是否能引起测量误差及误差大小.试验结果表明,含清除剂少的水样,对氯苯甲酸测量OH#浓度时会引起很大的误差.在对氯苯甲酸捕获率小于10%的水样中,对氯苯甲酸测量OH#时产生的误差小.在捕获率大于20%的水样中,采用对氯苯甲酸测量OH#会产生较大误差,不能用来测量OH#浓度.
- Abstract:There are errors when applying para-chlorobenzoic acid (pCBA) to measure OH# radicals during ozonation processes. To investigate the errors, batch tests were carried out to measure the ozone decay rate k. The variation of k values of oxalate, toluene and humic acid samples with or without pCBAcould tell whether the used pCBAleaded to a detectable error and how big of the error. The results showed that pCBAleaded to obvious errors when it was used to detect OH# radicals in low scavenger containing samples. In samples, when the pCBAscavenging rate was less than10%, the error of using pCBAto detect OH# radicals is small. However, when the pCBAscavenging rate was over 20% in some samples, the used pCBAfor detection of OH# radicals leaded to evident errors, and it was not suitable to be used to detect OH# radicals.
摘要点击次数: 2123 全文下载次数: 3483