摘要
本文针对KMnO4、ClO2、NaClO、O3、H2O2去除饮用水中戊基硫醚(diamyl sulfide,DAS)和丙基硫醚(dipropyl sulfide,DPS)进行了研究.在中性室温条件下选取KMnO4、ClO2、NaClO、O3、H2O25种氧化方式氧化2000 ng·L-1 DPS、DAS,并探究其去除效果、氧化动力学及氧化机理.实验结果表明,5种氧化方式氧化2000 ng·L-1的DPS、DAS 2 h后,DPS、DAS去除率大多数都达到了90%以上,DPS、DAS氧化后剩余浓度大多低于其嗅阈值;根据动力学常数计算,高锰酸钾与DPS、DAS的二级反应动力学常数分别为2.30×104、1.74×104 L·mol-1·min-1;O3、H2O2氧化结果表明,O3氧化效果明显高于其他氧化方式,但单独使用H2O2效果不及其他氧化剂;ClO2、NaClO在硫醚的氧化中效果显著,去除率接近100%;高锰酸钾在氧化中存在色度问题,当水体中DPS、DAS浓度水平较高时高锰酸钾适用性不强;高锰酸钾、次氯酸钠、二氧化氯等氧化剂会使DPS、DAS氧化成砜类物质,本研究中识别出二戊基砜(diamyl sulfone)、二丙基砜(dipropyl sulfone).
KMnO4,ClO2,NaClO,O3 and H2O2 were selected as five types of oxidants to examine their removal efficiency towards diamyl sulfide(DAS)and dipropyl sulfide(DPS)in drinking water.The experiment was carried out in neutral conditions at room temperature with the sulfides initial concentration of 2000 ng·L-1.The oxidation removal efficiency,kinetics and mechanisms were systematically studied.The results indicated that the five oxidants were all efficient on removing selected sulfides and their removal rate were over 90%after 2 h oxidation.The residual concentration of selected sulfides was below threshold value after oxidation.According to the results from kinetic experiments,the second-order reaction kinetic constants k of DPS and DAS by KMnO4 oxidation was 2.30×104 L·mol-1·min-1 and 1.74×104 L·mol-1·min-1,respectively.O3 was more efficient than other oxidants on removing DPS and DAS.Meanwhile,the removal rate of DPS and DAS with ClO2 or NaClO was up to 100%.However,the removal of DPS and DAS was insignificant by H2O2.Despite KMnO4 was efficient,the color issue caused by KMnO4 might restrict its application.After oxidation,the transformation products of the selected sulfides by KMnO4,ClO2 and ClO2 were identified by GC-MS,which were diamyl sulfone and dipropyl sulfone.
作者
廖宇
张慧鑫
李璐玮
陈祎思
张君枝
LIAO Yu;ZHANG Huixin;LI Luwei;CHEN Yisi;ZHANG Junzhi(Beijing Climate Change Respond Research and Education Centre,Beijing University of Civil Engineering and Architecture,Beijing,100044,China)
出处
《环境化学》
CAS
CSCD
北大核心
2020年第5期1254-1261,共8页
Environmental Chemistry
基金
北京市教委科研计划(KM201810016009)
国家自然科学基金青年科学基金(51408022)
国家重大科技水专项(2015ZX07406001)资助
