Removal of a type of endocrine disruptors-di-n-butyl phthalate from water by ozonation

Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate （DBP） was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration were investigated. In addition, the activities of radicals on uncatalysed and catalysed ozonation were studied. The degradation intermediate products were followed and the kinetic of the ozonation were assessed as well. Results revealed that ozonation of DBP followed two mechanisms. Firstly, the reaction rate of direct ozonation was slower at lower pH, temperature, and ionic strength. Secondly, when these factors were increased for indirect radical reaction, higher percentage of DBP was removed with the increase of the initial ozone dosage and the decrease of the initial DBP concentration. In addition, tea-butanol, humic substances and Fe（Ⅱ） affected DBP ozonation through the radical pathway. It was determined that ozonation was restrained by adding tea-butanol for its radical inhibition effect. Furthermore, humic substances enhanced the reaction to some extent, but a slight negative effect would be encountered if the optimum dosage was exceeded. As a matter of fact, Mn（Ⅱ） affected the ozonation by ＂active sites＂ mechanism. In the experiment, three different kinds of intermediate products were produced during ozonation, but the amount of products for each one of them decreased as pH, temperature, ionic strength and initial ozone dosage increased. A kinetic equation of the reaction between ozone and DBP was obtained.     

无机吸附剂负载的TiO2降解有机污染物研究进展

纳米TiO2光催化剂在废水处理、空气净化等环保领域有着诱人的应用前景,将其负载于一定的载体上,尤其是无机吸附剂上．并设计出高效的光反应器是其实用化和工业化的关键所在。论述了纳米TiO2在无机吸附剂上的负载及其在有机污染物处理中的应用,并对相关的光催化反应器做了相应的介绍。     

聚磷酸钙可降解纤维研究

为解决材料在环境中的降解问题,制备了聚磷酸钙纤维．研究表明其结构为无定形玻璃态,抗拉强度为１．９０ＧＰａ,弹性模量为６７．５ＧＰａ,并可发生化学降解,故可作为可降解复合材料的增强纤维     

SBR生物技术处理竹浆造纸黑液的研究

通过循环序间歇式活性污泥法（ＳＢＲ）处理可使经酸析木质素后所得黑液中的ＢＯＤ５和ＣＯＤ显著减少,当进水中ＣＯＤ浓度为１０９０－１１７０ｍｇ／Ｌ时,ＢＯＤ５去除率为７０％－８３％,ＣＯＤ去除率为５４．５％－６３％,出水中ＢＯＤ５和ＣＯＤ的浓度分别为７６－１０１ｍｇ／Ｌ和４１９－５００ｍｇ／Ｌ,内电解与ＳＢＲ联合对黑液的处理更为有效,当进水ＣＯＤ浓度为１０４６－１１００ｍｇ／Ｌ,ＢＯＤ５和ＣＯＤ去除率     

4种农药对3种拟菊酯杀虫剂在不同光源下的光解效应

以太阳光、氙灯、高压汞灯为光源,研究了哒嗪硫磷、多菌灵、克百威、丁草胺4种农药对氯氰菊酯、溴氰菊酯、氰戊菊酯3种拟菊酯杀虫剂的光解速度及光解效应的影响。结果表明：哒嗪硫磷、多菌灵对氯氰菊酯等3种拟菊酯杀虫剂在3种不同光源的光照处理下均表现出光敏降解效应;然而在太阳光及高压汞灯光源的光照处理下,克百威和丁草胺对３种拟菊酯杀虫剂具有光猝灭降解作用。太阳光照射下氯氰菊酯等3种拟菊酯杀虫剂的光解率与其单位面积上的药剂剂量成反比;而哒嗪硫磷等4种农药对3种拟菊酯杀虫剂的光敏或光猝灭效率与此4种农药的剂量成正相关     

聚乙烯醇生化矿化度及自然降解的研究

通过对聚乙烯醇(PVA)生化矿化度、PVA在目然水域及土壤中的自净能力以及PVA降解过程中结构变化的研究,探讨PVA的可生化性及降解进程中物质的转化规律.PVA的生化矿化度高达50-70％,表明PVA在微生物作用下可以高度降解.由自净能力和结构变化过程的研究表明,PVA首先由大分子转变为小分子,经相应时间后向无机物转化,说明PVA在自然水域和土壤中有较好的自净作用。     

河水中水合肼降解规律的探讨

本文通过室内及室外实际河流的监测,证明了水合肼的降解符合动力学一级反应。降解速度受水温、微生物、溶解氧、pH等因素影响,水温高,有微生物的存在,富氧及pH在6—8之间的条件下,降解速度快。温度对降解的影响符合K_T=K_(20)θ~((T-20))公式。利用微机计算出K_(20)与θ,结果pH为6时K_(20) 0.0281~1/h,θ1.045,pH为8时K_(20) 0.021~1/h,θ1.036,计算与实测降解系数平均误差分别为1.17％和-10.7％。在所实验的河流中,水合肼的降解系数为0.300~1/h平均误差为-5.87％。     

苯二甲酸酯的微生物降解与转化

综述国内外有关苯二甲酸酯化合物对环境的污染以及微生物对该类物质的降解与转化,指出：①ＰＡＥｓ已在全球范围的大气、水体、土壤中达到了普遍检出的程度;②微生物能够降解利用ＰＡＥｓ;③ＰＡＥｓ的微生物降解反应速率符合一级反应动力学方法方程;④混合微生物的联合代谢作用较纯培养降解ＰＡＥｓ效果好;⑤ＰＡＥｓ在微生物酶的作用下,先水解生成单酯与苯二甲酸,然后在好气条件下进行代谢与转化,最终可生成ＣＯ２和水。     

微波紫外协同降解染料活性艳红X-3B研究

将微波激发的无极紫外灯应用于染料废水的处理研究,考察了反应过程中染料废水脱色率、TOC去除率、溶液pH以及反应前后染料废水高效液相色谱图的变化情况。染料活性艳红X-3B经无极紫外光处理110min后,脱色率达96％,TOC去除率达66％,降解效果明显好于单独使用微波或普通紫外灯的降解效果总和,溶液pH先降低后缓慢升高。     

二氧化钛薄膜光催化性能的影响因素及提高途径

TiO2薄膜光催化技术有广阔的应用前景,在国内外得到了广泛的研究。介绍了TiO2薄膜光催化降解的研究现状,指出了影响薄膜光催化性能的若干因素和提高薄膜光催化效率的相应手段。另外,对金属复合、半导体复合对TiO2薄膜光催化性能的影响和可见光催化的研究现状进行了评述。