NaClO催化氧化法降解活性黄X-R废水和该方法的适用范围  

Degradation of reactive yellow X-R wastewater by NaClO catalytic oxidation method and its application scope

作　　者：徐文英 高浩阳 XU Wenying;GAO Haoyang(College of Environmental Science and Technology,State Key Laboratory for Pollution Control&Resource Reuse,Tongji University,Shanghai,200092,China)

机构地区：[1]同济大学环境科学与工程学院,污染控制与资源化研究国家重点实验室,上海200092

出　　处：《环境化学》2022年第3期1011-1021,共11页Environmental Chemistry

基　　金：印染废水降解新工艺的开发(kh0040020183321)资助.

摘　　要：采用NaClO催化氧化法对活性黄X-R废水进行了脱色降解的系统研究,探讨了反应条件对脱色效果的影响,分析了染料的降解机理。结果表明,该方法对染料的脱色率不到50%,脱色率随着染料和有效氯浓度的增加而略微增大,随着初始pH的上升而减小,催化剂的投加对脱色率的影响甚微。NaClO氧化法的对比实验结果表明,NaClO的直接氧化在催化氧化降解过程中起了主导作用,原子氧的作用次之。自由基清除剂实验结果也证明了这一点。定量分析了活性黄X-R和另外2种偶氮染料的分子结构与NaClO催化氧化法对其脱色效果的关系(QSPR分析),结果表明,染料分子结构中磺酸基数目和无机性值与有机性值的比值对脱色率有较强的影响,磺酸基数目的影响尤为突出。NaClO催化氧化法更加适合于降解K型活性染料、含有磺酸钠盐的酸性染料和苯环染料,因为它们具有较强的耐氯牢度。采用XPS、XRD和SEM法对催化剂进行表征,结果发现其表层化学吸附氧的比例随着催化剂使用时间的延长略微减小,表层里含有β-NiOOH和β-Ni(OH)_(2),且牢牢附着在氧化铝小球表面,不易脱落造成二次污染。The decolorization and degradation of reactive yellow X-R wastewater were systematically studied by NaClO catalytic oxidation method.The effects of reaction conditions on decolorization were discussed,and the degradation mechanism of the dye was analyzed.The results showed that the decolorization rate of the dye by this method was lower than 50%.The decolorization rate increased slightly with dye and available chlorine concentration,and decreases with initial pH.The addition of the catalyst had little influence on the decolorization rate.The comparative experiment results of NaClO oxidation showed that the direct oxidation of NaClO played a leading role,followed by atomic oxygen in the catalytic oxidation degradation process.The experimental results of free radical scavengers also confirmed this point.The relationship between the molecular structure of reactive yellow X-R and other two azo dyes and the decolorization effect of NaClO catalytic oxidation method(QSPR analysis)was quantitatively analyzed.The results showed that the number of sulfonic acid groups in dye molecular structure and the ratio of inorganic value to organic value had great influence on the decolorization rate,especially the number of sulfonic acid groups.NaClO catalytic oxidation is more suitable for degradation of K reactive dyes,acid dyes containing sodium sulfonate and benzene ring dyes,because they have stronger chlorine fastness.The catalyst was characterized by XPS,XRD and SEM.The results showed that the proportion of chemisorbed oxygen in the surface layer decreased slightly with the prolonging of catalyst service time,andβ-NiOOH andβ-Ni(OH)_(2) were contained in the surface layer,which was firmly attached to the surface of alumina beads and was not easy to fall off and cause secondary pollution.

关 键 词：羟基氧化镍 NACLO 催化机理 活性黄X-R QSPR分析 

分 类 号：X703[环境科学与工程—环境工程]