臭氧氧化降解水中四丁基锡效能及动力学研究  

Degradation efficiency and kinetics of tetrabutyltin in aqueous solution by ozonation

作　　者：李学艳[1] 王永喜[1] 黄勇[1] 沈吉敏[2] 

机构地区：[1]苏州科技学院环境科学与工程学院,苏州215011 [2]城市水资源与水环境国家重点实验室,哈尔滨工业大学市政环境工程学院,哈尔滨150090

出　　处：《环境科学学报》2013年第5期1272-1277,共6页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.51108291);哈尔滨工业大学城市水资源与水环境国家重点实验室开放基金项目(No.QA201018)~~

摘　　要：对水中臭氧氧化降解四丁基锡(TeBT)的反应动力学、效能及影响因素进行了实验研究.结果表明,温度从12℃升到22℃,TeBT的去除率可从36%升高到43%,但当温度升到32℃时其去除率有所下降.pH升高有利于TeBT的氧化降解,在pH=5.9的缓冲溶液中,前10min TeBT的去除率为30%;在pH=8.0的缓冲溶液中,前10min TeBT的去除率提高到42%.原因可能是pH的升高会使臭氧在水中的分解速率加快,臭氧向水相转移率也提高.·OH抑制剂叔丁醇和重碳酸盐对臭氧氧化去除TeBT具有明显的抑制作用,说明在臭氧氧化去除TeBT的过程主要受到·OH产率的影响.通过拟一级反应动力学,计算出单独臭氧(即臭氧分子)与TeBT的直接反应速率常数kO3=435.79L·mol-1·s-1,·OH与TeBT的间接反应速率常数k·OH=1.4×109L·mol-1·s-1.The effects of parameters such as temperature and solution pH on ozonation of tetrabutyhin （TeBT） in aqueous solution were investigated. Oxidation kinetics of TeBT with ozone alone and hydroxyl radical were also investigated. Results show that the removal efficiency of TeBT increases from 36% to 43% with temperature increasing from 12 ℃ to 22 ℃. However, the removal efficiency decreases to 32% when the temperature rises to 32 ℃, as a result of accelerated useless decomposition of ozone with increased temperature. Higher pH of solution favors the ozonation of TeBT. The degradation efficiency of TeBT in 10 min increases from 30% to 42% when solution pH changes from 5.9 to 8.0. Possible reason is that the decomposition of ozone is faster at a higher pH value and the transfer efficiency of ozone to the liquid phase increases （ This may be due to the faster decompositon of ozone and the enhancement of transfer efficiency of ozone to the liquid phase at a higher pH value）. The ozonation of TeBT is strongly inhibited by tert-Butyl alcohol （t-BuOH） and bicarbonate, the scavengers of · OH, which indicated that degradation of TeBT is mainly affected by the yield of · OH during TeBT ozonation process. According to the pseudo-first order kinetics, the rate constants for the reaction of TeBT with ozone alone, molecular ozone （ko3） and · OH （k .os ） are determined as 435.79 L·mol^-1·s^-1 and 1.4 × 10^9 L·mol^-1·s^-1, respectively.

关 键 词：四丁基锡 臭氧 羟基自由基 反应动力学 速率常数 

分 类 号：X703.1[环境科学与工程—环境工程]