摘要
对氯苯甲酸被用于臭氧氧化过程中羟基自由基的测量,为了检验对氯苯甲酸是否在测量过程中出现误差,进行了臭氧氧化对氯苯甲酸的间歇实验和半连续实验.结果表明,中性条件下间歇试验中,对氯苯甲酸可以强烈促进臭氧分解,它促进臭氧分解的能力比典型的促进剂甲酸和甲醇高10倍.半连续试验的结果进一步表明,臭氧氧化对氯苯甲酸时,可以形成中间产物过氧化氢,过氧化氢能和臭氧反应,形成大量的OH.,从而改变O3/OH.的链式反应,导致采用对氯苯甲酸测量OH.时出现误差.
Para-chlorobenzoic acid (pCBA) was used to detect the concentration of OH· radicals during ozonation processes. The batch tests and semi continuous tests of ozonation of pCBA were carried out in order to check whether there was an error during the measurement. The results indicated that pCBA promoted the decomposition of ozone strongly in the batch tests under neutral pH conditions. Its promotion ability was 10 times higher than those of formic acid and methanol. The semi continuous tests exhibited further that the intermediate product, hydrogen peroxide could be formed during ozonation of pCBA. And the generated hydrogen peroxide reacted quickly with ozone and produced a quite amount of hydroxyl radicals. Therefore, the chain reaction of O3/OH· was changed. It resulted in errors if the measurement of hydroxyl radicals by using pCBA.
出处
《环境科学学报》
CAS
CSCD
北大核心
2005年第11期1555-1559,共5页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.50325824)
中国博士后科学基金~~
关键词
臭氧
对氯苯甲酸
羟基自由基
过氧化氢
Ozone
para-chlorobenzoic acid
OH· radicals
hydrogen peroxide