治理技术邻苯二甲酸二辛酯废水的处理

采用压滤-刮油-中和吸附-压滤-吸附工艺处理邻苯二甲酸二辛酯废水,对处理工艺的运行条件进行了探讨.出水COD和石油类的去除率分别达到97.7%和99.8%.该法设备简单、投资少、操作方便,对排放量较小的邻苯二甲酸二辛酯废水的处理是行之有效的方法.     

邻苯二甲酸二丁酯污染对苦草生理生化指标的影响

以沉水植物苦草为试验材料,通过模拟实验研究了邻苯二甲酸二丁酯(DBP)长期暴露对苦草的生长状况以及丙二醛、可溶性糖、叶绿素、谷胱甘肽、蛋白质和氨基酸的含量等生理生化指标的影响,试验结果表明：高浓度DBP长期暴露对苦草生长有严重伤害,DBP对苦草丙二醛和可溶性糖含量以及叶片中叶绿素含量的影响比较相似,都有一定的起伏．在DBP胁迫下,苦草中氨基酸总量和蛋白质含量与对照组相比呈下降趋势．苦草体内谷胱甘肽(GSH)含量明显低于对照,且随DBP浓度的升高GSH含量下降,统计分析表明有显著性差异．因此,谷胱甘肽含量可以考虑作为DBP对沉水植物早期伤害的指标．     

Fenton试剂—好氧活性污泥法处理邻苯二甲酸二丁酯废水

采用Fenton氧化—好氧活性污泥法处理邻苯二甲酸二丁酯（DBP）废水,优化了Fenton氧化反应的工艺条件。实验结果表明：在H₂O₂加入量4 g/L、Fe²⁺加入量200 mg/L、反应温度60 ℃、废水pH 4、反应时间60 min的最佳工艺条件下,Fenton氧化出水COD为200~250 mg/L,DBP质量浓度约为0.10 mg/L;在污泥质量浓度2 000 mg/L、DO 2~3 mg/L、水力停留时间8 h的条件下,好氧活性污泥法处理出水的COD基本低于50 mg/L,DBP质量浓度约为0.05 mg/L,均满足GB 8978—1996《污水综合排放标准》,可达标排放。     

松花江表层沉积物PAEs分布特征及生态风险评价

为揭示松花江干支流表层沉积物中邻苯二甲酸酯类(phthalate esters,PAEs)的空间分布特征及其生态风险状况本文利用气相色谱三重四级杆质谱联用仪(GC-MS)对松花江干支流表层沉积物中6种PAEs的含量分布和组成特征进行了分析,并采用商值法和环境风险水平(ERL)法对其生态风险状况进行评价.结果表明:①松花江干支流沉积物6种邻苯二甲酸酯(∑_6PAEs)含量范围(以干重计)为6 832.5～36 298.9ng·g~(-1)(平均值为18388.6ng·g~(-1)),邻苯二甲酸(2-乙基己基)酯(DEHP)和邻苯二甲酸二丁酯(DBP)为主要组分,干流点位∑_6PAEs含量(6 832.5～36 298.9 ng·g~(-1),平均值为18 616.9ng·g~(-1))与支流点位∑_6PAEs(10 367.6～26 593.3ng·g~(-1),平均值为18 264.1ng·g~(-1))差异不显著(P0.05),支流点位各PAEs单体含量与干流点位差异不大.从上游到下游干支流∑_6PAEs含量呈现先降后升的趋势.农业自然区域∑_6PAEs平均含量(18 677.5 ng·g~(-1))与城市工业区域(18 063.7 ng·g~(-1))相近(P0.05),DBP和DEHP是两区域内的主要PAEs两者平均值贡献率高达98%以上.②松花江干支流表层沉积物中∑_6PAEs主要来源于人类日用品、农业生产以及含有增塑剂的工业生产.③松花江表层沉积物中DMP和BBP对水生生物无生态风险,DEP具有低水平生态风险,而DEHP和DBP对水生生物具有高生态风险.     

酸化蛭石的表面有机修饰及其对疏水性微污染物的吸附

插层法制备有机黏土存在比表面积低、负载不均等问题,限制了此类材料吸附性能的进一步提高.基于此,通过选择性酸浸的方法预处理天然蛭石,以三甲基氯硅烷(CTMS)和三乙基氯硅烷(CTES)对其进行表面有机修饰,利用FTIR、BET、SEM和热重等方法对材料进行表征.结果表明,改性酸化蛭石的比表面积可达361.0 m2.g-1,而有机插层蛭石的比表面积仅为6.0m2.g-1,有机基团更稳定地以共价键形式负载于酸化蛭石表面.以疏水性有机微污染物邻苯二甲酸二乙酯(DEP)为测试目标,考察材料的吸附性能.在本实验条件下,测得CTES改性酸化蛭石、CTMS改性酸化蛭石和有机插层蛭石对DEP的吸附量分别为63.7、51.2和15.7 mg.g-1,证明有机修饰后的酸化蛭石具有更强的疏水性吸附能力,有机负载的均匀性是决定吸附能力的关键因子.动力学研究表明吸附行为遵循拟二级动力学方程;吸附等温线表现出线性特征,可由Henry和Freundlich模型进行描述,表明分配作用是吸附过程的主要机制.     

Efficient microwave-assisted photocatalytic degradation of endocrine disruptor dimethyl phthalate over composite catalyst ZrOx/ZnO

A highly active ZrOx/ZnO catalyst for microwave-assisted photocatalytic (MW/PC) degradation of endocrine disruptor dimethyl phthalate (DMP) has been prepared via cetyltrimethylammonium assisted hydrothermal method. The ZrOx/ZnO was characterized by XPS, XRD, UV-Vis, BET and SEM techniques. The XPS result showed that Zr oxides with different valences (+2, +3, +4) co-existed in ZrOx/ZnO. By using the ZrOx/ZnO (0.1 g), the TOC removal efficiency of DMP (100 mL of 50 mg/L) was 88% after 30 min reaction, which was about 15% higher than P25 TiO2. It was found that the removal process of DMP by MW/PC followed pseudo first-order kinetics in all cases, and ZrOx/ZnO significantly accelerated the degradation of DMP. The degradation half-life time of DMP was shortened 45% compared with P25 TiO2. A possible catalytic mechanism was proposed based on microwave response and interfacial charge transfer. ZrOx/ZnO could be reused for six times without obvious decrease in catalytic activity. The study offers new insights into designing highly efficient catalysts for MW/PC process and is applicable for MW/PC environmental remediation.     

Activated sludge-mediated biodegradation of dimethyl phthalate under fermentative conditions

The biodegradation of dimethyl phthalate(DMP)was investigated under fermentative conditions in this study.The nature of the intermediate compounds and the extent of mineralization were probed using high-pressure liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC-MS)methods.The fermentative bacteria were able to biodegrade the DMP under anaerobic conditions,with the biodegradation rate of 0.36 mg DMP/(L·h).The results demonstrated that the DMP degradation under fermentative conditio...     

环境中的PAES对蟾蜍蝌蚪红细胞微核的影响研究

通过对邻苯二甲酸酯对蟾蜍蝌蚪红细胞微核的影响进行了研究。目的探讨邻苯二甲酸酯对蟾蜍蝌蚪的致突变作用。方法以邻苯二甲酸二甲酯为污染物对蟾蜍蝌蚪染毒24小时,并观察其细胞核变化。所用蟾蜍蝌蚪处于变态期,对污染物较为敏感。结果邻苯二甲酸酯使蟾蜍蝌蚪红细胞微核率以及核异常细胞率上升,微核率随着浓度的增大而上升,在浓度为78 ug/ml,对照组相比有极显著差异P〈0.01,浓度在18.5 ug/ml时试验组突变的细胞核的形态发生显著改变,核异常细胞率与对照组核异常细胞率有显著差异P〈0.05。此时显微镜下观察可见微核、双核、核内凹、核碎裂、无丝分裂时核分裂不均等核的形态变化。结论邻苯二甲酸酯对蟾蜍蝌蚪具有明显的致突变作用。     

常见有机物对催化臭氧化降解水中硝基苯的影响

考察了有机物甲醛、甲醇、甲酸和邻苯二甲酸二丁酯对单独臭氧氧化和蜂窝陶瓷催化臭氧化工艺去除水中硝基苯降解效果的影响规律.单独臭氧氧化和蜂窝陶瓷催化臭氧化对硝基苯的去除率随着甲醛浓度的升高(0～12 mg·L-1)分别降低了11.6%和9.6%;2种工艺对硝基苯的去除率都随着甲醇浓度的增加(0～16mg·L-1,)先增高再降低,单独臭氧氧化和蜂窝陶瓷催化臭氧化分别在浓度为2 mg·L-1和4 mg·L-1时去除率达到最大值;随着甲酸浓度的增加(0～8 mg·L-1)去除率也都先增高再降低,单独臭氧氧化和蜂窝陶瓷催化臭氧化分别在浓度为0.5 mg·L-1和2 mg·L-1时去除率达到最大值;低浓度的甲醇和甲酸促进了硝基苯的降解,高浓度的甲醇和甲酸抑制了硝基苯的降解.单独臭氧氧化和蜂窝陶瓷催化臭氧化在邻苯二甲酸二丁酯浓度增加(0～10 mg·L-1)的情况下对硝基苯的去除率分别降低了19.7%和18.6%.     

Electrochemical incineration of dimethyl phthalate by anodic oxidation with boron-doped diamond electrode

The anodic oxidation of aqueous solutions containing dimethyl phthalate (DMP) up to 125 mg/L with sodium sulfate (Na2SO4) as supporting electrolyte within the pH range 2.0–10.0 was studied using a one-compartment batch reactor employing a boron-doped diamond (BDD) as anode. Electrolyses were carried out at constant current density (1.5–4.5 mA/cm2). Complete mineralization was always achieved owing to the great concentration of hydroxyl radical (.OH) generated at the BDD surface. The e ects of pH, apparent current density and initial DMP concentration on the degradation rate of DMP, the specific charge required for its total mineralization and mineralization current e ciency were investigated systematically. The mineralization rate of DMP was found to be pH-independent and to increase with increasing applied current density. Results indicated that this electrochemical process was subjected, at least partially, to the mass transfer of organics onto the BDD surface. Kinetic analysis of the temporal change of DMP concentration during electrolysis determined by High Performance Liquid Chromatography (HPLC) revealed that DMP decay under all tested conditions followed a pseudo first-order reaction. Aromatic intermediates and generated carboxylic acids were identified by Gas Chromatography- Mass Spectrometry (GC-MS) and a general pathway for the electrochemical incineration of DMP on BDD was proposed.