Biodegradability of four phthalic acid esters under anaerobic condition assessed using natural sediment

Biodegradability of di-n-butyl phthalate （DBP）, butylbenzyl phthalate （BBP）, di-ethylhexyl phthalate （DEHP）, and di-isononyl phthalate （DINP） under an anaerobic condition was evaluated using three natural sediment microcosms obtained from ponds in Osaka, which had not been significantly polluted by the chemicals. The degradabilities of the four phthalic acid esters（PAEs） were analyzed by a first-order kinetic model with a lag phase and ranked as DBP〉BBP〉〉DEHP〉DINP. The PAEs with shorter alkyl-chains, DBP and BBP, were degraded with quite short lag phases near to zero and short half-lives of a few days. The PAEs with longer alkyl-chains, DEHP and DINP, were degraded with lag phases of 5-30 d and the quite long half-lives of a couple of hundred days. Although no data was available on the anaerobic biodegradability of D1NP before this study, it was clarified that DINP can be degraded with slow degradation rates. The fact that all the three intact sediments were capable of biodegradation of the PAEs suggests that potential of anaerobic biodegradation of PAEs is widespread in the aquatic environment.     

邻苯二甲酸酯的摇瓶生物降解规律研究

用好氧活性污泥对 9种邻苯二甲酸酯进行了摇瓶生物降解研究 ,结果表明 ,邻苯二甲酸酯的摇瓶降解速率符合一级动力学 ,速率常数 (kb)与化合物的分子结构之间存在相关关系 ,其表达式为lnkb=0 0 2 6 2x2 - 0 6 6 7x +2 15 2 (r =0 976 ) ;降解半衰期与烷基链之间也存在相关性 ,表达式为t1 2 =0 0 391x2 +0 0 95 3x - 0 0 2 5 9(r=0 972 ) .邻苯二甲酸二甲酯 (DMP)浓度超过 6 0mg·L-1时 ,其自身降解速率下降 ,邻苯二甲酸盐浓度超过 5 0 0mg·L-1时 ,对邻苯二甲酸二乙酯 (DEP)的降解有抑制作用     

塑料包装物中邻苯二甲酸酯的分布统计分析

选取36种日用塑料包装物作为研究对象,采用方差分析和多重比较检验等统计方法,对其所含6种优先控制污染物—邻苯二甲酸酯(PAEs)的分布特点进行统计分析.结果表明,仅有2.78%的塑料样品没有PAEs被检出,50%的样品含有2种或2种以上PAEs;其中邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二(2-乙基)己酯(DEHP)分布最为广泛,存在于97.22%的样品中.塑料包装袋的来源、色彩与其ΣPAEs具有较高的关联性,菜市场包装袋的ΣPAEs显著高于超市塑料包装袋和一次性塑料包装袋的ΣPAEs;彩色塑料包装袋中ΣPAEs高于非彩色塑料包装袋;在材质中加入颜料的塑料包装袋其ΣPAEs明显高于表面彩绘的塑料包装袋.     

花生对土壤中邻苯二甲酸酯的吸收累积特征

选择邻苯二甲酸二丁酯(Dibutyl phthalate,DBP)和邻苯二甲酸二(2-乙基己基)酯(di-(2-ethylhexyl)phthalate,DEHP)作为目标污染物,通过盆栽试验研究花生(Arachis hypogaea)对土壤中邻苯二甲酸酯的吸收累积特征.结果表明:邻苯二甲酸酯污染对青花7号花生生物量无显著影响,而青花5号花生生物量则显著降低,在污染水平I(40 mg·kg-1)和污染水平II(80 mg·kg-1)下花生籽粒产量分别减少24.11%和48.75%.随着土壤中邻苯二甲酸酯污染水平的增高,花生植株各部位的DBP和DEHP含量均呈显著升高趋势,花生根系DBP和DEHP含量显著高于其它部位.在2个污染水平下,花生籽粒对DBP和DEHP的富集量占植株富集总量的比例最高.花生种植后土壤中邻苯二甲酸酯残留量均有所降低,在相同的污染水平下DEHP残留量显著高于DBP.花生籽粒对DBP的富集系数高于DEHP的生物富集系数,分别介于0.50~1.87和0.53~0.98之间.     

水溶液中嗪草酮的光化学行为研究

以氙灯为光源模拟太阳光,研究了农药嗪草酮(MT)在水溶液中的光降解;探讨了pH值以及天然水体中广泛存在的光敏荆腐殖酸、硝酸根和Fe3+等对嗪草酮间接光解的影响;测量了嗪草酮量子产率及其与活性氧类物种(ROS)·OH和1O2的反应速率常数.结果表明,在pH值3.5-9.5范围内,嗪草酮直接光降解速率随pH值升高而降低.pH=7时,腐殖酸具有光屏蔽作用而抑制嗪草酮光降解,硝酸根和Fe3+对嗪草酮间接光降解基本没有作用.嗪草酮与1O2反应速率常数为0 mol-1·L·s-1,与·OH反应速率常数为5.7×109mol-1Ls-1.在天然水体中嗪草酮与·OH反应最小半衰期为68 h,远远大于北纬40.(40°N)下直接光解半衰期.以上研究结果表明,嗪草酮直接光解占主导作用,其量子产率为0.01.预测在40°N春、夏、秋、冬时嗪草酮直接光解半衰期分别为1.44、1.08、2.58和5.10h,室外太阳光照实验结果显示,在40°N秋季嗪草酮的半衰期为2.98 h,与理论预测值接近.     

黄河中下游水体中邻苯二甲酸酯的分布特征

采集了黄河中下游12个断面的河水、沉积物和悬浮颗粒物样品,用气相色谱法对样品中邻苯二甲酸酯类(PAEs)有机物含量进行测定,分析其在黄河水体中的分布特征.结果表明,在小浪底-东明桥之间,干流水相PAEs浓度分布范围为3.99×10^-3～45.45×10^-3mg/L;支流浓度范围为15.80×10-3～49.53×10^-3mg/L,远远高于干流的浓度.在所研究支流中,洛阳石化污水沉积相中的PAEs含量最高,达到331.70mg/kg;PAEs在干流各断面沉积相中的浓度变化范围为30.52～85.16mg/kg;沿程变化主要受支流的汇入和各处沉积物理化性质的影响.在干流焦巩桥至东明桥区间,悬浮颗粒相的PAEs总量水平沿程呈上升趋势,浓度由40.56mg/kg增至94.22mg/kg.邻苯二甲酸双(2-乙基己基)酯(DEHP)和邻苯二甲酸二丁酯(DBP)所占比例相对较大.干流与支流水相中的DEHP,除孟津和焦巩大桥处未超标,其余各处均已超标.     

Concentration and source identification of polycyclic aromatic hydrocarbons and phthalic acid esters in the surface water of the Yangtze River Delta, China

The pollution from polycyclic aromatic hydrocarbons (PAHs) and phthalic acid esters (PAEs) in the surface water of the rapidly urbanized Yangtze River Delta region was investigated. Fourteen surface water samples were collected in June 2010. Water samples were liquid-liquid extracted using methylene chloride and analyzed by gas chromatography-mass spectrometry. Concentrations of PAHs and PAEs ranged 12.9-638.1 ng/L and 61-28550 ng/L, respectively. Fluoranthene, naphthalene, pyrene, phenanthrene, di-2-ethylhexyl phthalate, and di-n-butyl phthalate were the most abundant compounds in the samples. The water samples were moderately polluted with benzo[a]pyrene according to China's environmental quality standard for surface water. The two highest concentrations of PAHs and PAEs occurred in samples from Taihu Lake, Wuxi City and the western section of Yangchenghu Lake. Potential sources of pollution at S7 were petroleum combustion and the plastics industry, and at Yangchenghu Lake were petroleum combustion and domestic waste. Pollution in samples from the Beijing-Hangzhou Grand Canal originated from diesel engines. There were no obvious sources of pollution for the other water samples. These results can be used as reference levels for future monitoring programs of pollution from PAHs and PAEs.     

水稻土施用城市污泥盆栽通菜土壤中邻苯二甲酸酯(PAEs)的残留

应用GC/MS联机检测技术对水稻土施用城市污泥盆栽通菜(Ipomoea aquatic)后土壤中6种邻苯二甲酸酯化合物(PAEs)进行分析.结果表明,盆载通菜土壤中6种PAEs的总含量(∑PAEs)在7.667-40.025 mg/kg之间,平均为26.137 mg/kg,其高低次序为佛山污泥>广州污泥>佛山污泥加化肥>广州污泥+化肥>空白>化肥.与空白对照相比,施用污泥和污泥+化肥处理的土壤中∑PAEs含量显著提高,但单施化肥的土壤中∑PAEs含量降低.不同处理土壤中的PAEs化合物是以一种或两种化合物为主,主要是DnBP和/或DEHP,显示了不同的PAEs分布特征.     

萝卜对邻苯二甲酸酯(PAEs)吸收累积特征及途径的初步研究

利用玻璃室处理和覆土处理(人工污染土壤上覆盖原土壤)的方法控制萝卜的PAEs来源进行盆栽试验,试验处理分别为:(1)原土壤,暴露于大气中(空白1);(2)原土壤,置于玻璃室中(空白2);(3)人工污染土壤,暴露于大气中;(4)人工污染土壤,置于玻璃室中;(5)人工污染土壤上覆盖2 cm厚原土壤,暴露于大气中;(6)人工污染土壤上覆盖2 cm厚原土壤,置于玻璃室中.盆栽后应用GC/MS对土壤和植株样品中的PAEs进行分析,初步研究了萝卜对PAEs的吸收累积特征及途径.研究结果表明,萝卜茎叶和直根中邻苯二甲酸二乙酯(DEP)的含量均低于检测限,邻苯二甲酸正二丁酯(DBP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)的含量与土壤污染浓度成正相关关系,DBP的含量高于DE-HP,两者主要分布在茎叶中.未覆土处理与覆土处理相比,前者盆栽的萝卜茎叶中DBP和DEHP的含量均高于后者,但在2个处理之间差异不显著,表明萝卜茎叶可以吸收污染土壤中挥发出来的DBP和DEHP,但直根吸收运移是茎叶中DBP和DEHP的主要来源途径.玻璃室处理导致萝卜茎叶中DBP含量的提高,在大棚蔬菜生产中值得注意.     

邻苯二甲酸酯及邻苯二甲酸在碳管上的吸附

以邻苯二甲酸(PA)和邻苯二甲酸二乙酯(DEP)为目标污染物,碳纳米管(CNTs)为吸附剂,通过不同pH值条件下单、双溶质的吸附实验,结合能量分布理论,分析PA对DEP在CNTs上的竞争和取代吸附.结果表明,在同一pH值下,DEP在CNTs上的吸附性强于PA.对于DEP,pH值改变导致的CNTs分散稳定性的变化是影响其...     

新农药硫肟醚在有机溶剂中的光解

以紫外灯为光源,对硫肟醚在甲醇、丙酮、正己烷和二甲苯等有机溶剂中的光解反应动力学及降解机理进行了初步研究.结果表明,硫肟醚在4种有机溶剂中的紫外光解反应符合一级动力学规律,在4种溶剂中反应速率常数分别为1·14×10-1(正己烷)、8·90×10-2(甲醇)、2·46×10-2(二甲苯)和4·51×10-3min-1(丙酮),硫肟醚的降解半衰期分别为6·08,7·79,28·18和153·86min.通过对硫肟醚光解产物进行分离和LC-MS鉴定,初步推出在紫外光辐射下硫肟醚在有机溶剂中的降解主要涉及到硫肟醚分子的肟醚键(CNOC)断裂、甲硫键(C—S—CH3)光氧化、脱氯反应和光异构化作用等途径.     

驯化活性污泥降解邻苯二甲酸酯类化合物的研究

研究利用驯化活性污泥生物降解３种邻苯二甲酸酯,即邻苯二甲酸二甲酯,二丁酯和二辛酯。结果表明;侧链较短的ＤＭＰ和ＤＢＰ能被较快地降解,分别在３ｄ和８ｄ内被降解９０％,但ＤＯＰ的降解速率较慢;３种ＰＡＥＳ的生物降妥过程均可用一级反应动力学模型描述,且实验测得的一级反应速率常数能与相应酯类的二级水解常数较好地关联。     

Photodegradation of α-naphthaleneacetic acid in aqueous solution

Ｉｎｔｒｏｄｕｃｔｉｏｎα ｎａｐｈｔｈａｌｅｎｅａｃｅｔｉｃａｃｉｄ (ＮＡＡ)ｉｓａｎｉｍｐｏｒｔａｎｔｐｌａｎｔｇｒｏｗｔｈｒｅｇｕｌａｔｏｒｕｓｅｄｎｏｔｏｎｌｙｔｏｐｒｅｖｅｎｔｔｈｅｐｒｅｈａｒｖｅｓｔｄｒｏｐｏｆａｐｐｌｅｓｂｕｔａｌｓｏａｓａｆｒｕｉｔｔｈｉｎｎｉｎｇａｇｅｎｔ (Ｗｏｒｔｈｉｎｇ ,1991) .ＭｕｃｈｒｅｓｅａｒｃｈｗｏｒｋａｂｏｕｔｔｈｅｅｆｆｅｃｔｏｆＮＡＡｏｎｐｌａｎｔｔｉｓｓｕｅｓ(Ｓｐｅｅｒ,1993;Ｈｉｄｅｙｏｓｈｉ,1993;Ｐｒａｓｄ ,1994 ) ,ｐｌａｎｔｇｒｏｗｔｈａ…     

紫外/过硫酸盐工艺降解水中氯贝酸的研究

采用紫外/过硫酸盐（UV/PS）工艺去除水中典型PPCPs类物质氯贝酸（CA）.考察了氯贝酸初始浓度、PS投加量、溶液初始pH值、碳酸氢根离子浓度、氯离子浓度和腐殖酸（HA）投加量共计6种因素对UV/PS工艺去除氯贝酸的影响.结果表明：UV/PS工艺降解氯贝酸与准一级动力学模型相符（R²>0.95）,准一级反应速率常数随氯贝酸初始浓度增加而减小.在一定的范围内,随着PS投加量的增加,氯贝酸的降解速率快速增加.不同的pH值环境对氯贝酸的降解有一定影响,溶液pH值从酸性到碱性再到强碱性的过程中,UV/PS工艺对氯贝酸的降解速率呈先加快后减慢的趋势.溶液中的碳酸氢根离子和氯离子都会对UV/PS工艺降解氯贝酸产生抑制作用,且两者对该反应的抑制作用大小关系为HCO₃^->Cl^-.HA的存在对UV/PS工艺去除氯贝酸有抑制作用.     

Effect of electron beam irradiation on the degradation of monochlorophenols in aqueous solution

Electron beam was successfully used for the degradation of 2-chlorophenol (2-CP) and 4-chlorophenol (4-CP) in aqueous solutions in this research. The effect of radiation dose on substrate degradation and dechlorination of solutions with concentration of 50mg/L was investigated. The effect of initial concentration, pH and presence of oxygen was also investigated. The concentration of 2-CP and 4-CP remaining in solution after irradiation were measured by HPLC. The results showed that increased radiation dose led to increased degradation of the chlorophenols and increased CI^- yield. Deaeration was also found to significantly increase the rate of degradation of chlorphenols in water while degradation and dechlodnation under alkaline condition was lower than at low to neutral pH.     

臭氧法降解水中对甲基苯磺酸的动力学研究

采用臭氧法降解对甲基苯磺酸废水,研究了对甲基苯磺酸降解的影响因素和动力学.考察了反应液初始浓度、初始pH值、臭氧投量、反应温度、常见无机离子等因素对臭氧氧化降解对甲基苯磺酸反应速率的影响.结果表明,对甲基苯磺酸初始浓度0.29mmol.L-1,pH9.0,臭氧投量3.75×10-6mol.s-1,控制温度25℃,反应6...     

Distribution and sources of polycyclic aromatic hydrocarbons and phthalic acid esters in water and surface sediment from the Three Gorges Reservoir

After the impoundment of the Three Gorges Reservoir(TGR), the hydrological situation of the reservoir has changed greatly. The concentration and distribution of typical persistent organic pollutants in water and sediment have also changed accordingly. In this study, the concentration, distribution and potential sources of 16 polycyclic aromatic hydrocarbons(PAHs) and 6 phthalic acid esters(PAEs) during the water drawdown and impoundment periods were investigated in water and sediment from the TGR. According to our results, PAHs and PAEs showed temporal and spatial variations. The mean ΣPAH and ΣPAE concentrations in water and sediment were both higher during the water impoundment period than during the water drawdown period. The water samples from the main stream showed larger ΣPAH concentration fluctuations than those from tributaries. Both the PAH and PAE concentrations meet the Chinese national water environmental quality standard(GB 3838-2002). PAH monomers with 2–3 rings and 4 rings were dominant in water, and 4-ring and 5–6-ring PAHs were dominant in sediment. Di-n-butyl phthalate(DBP) and di-2-ethylhexyl phthalate(DEHP)were the dominant PAE pollutants in the TGR. DBP and DEHP had the highest concentrations in water and sediment, respectively. The main source of PAHs in water from the TGR was petroleum and emissions from coal and biomass combustion, whereas the main sources of PAHs in sediments included coal and biomass combustion, petroleum, and petroleum combustion. The main source of PAEs in water was domestic waste, and the plastics and heavy chemical industries were the main sources of PAEs in sediment.     

电子束辐照降解水中氧氟沙星的研究

应用电子直线加速器初步探索了水体中氧氟沙星的辐照降解影响条件及降解机理.对初始浓度为20mg/L的氧氟沙星水溶液进行了辐照降解研究,分别选取了0.5kGy,1.0kGy,2.0kGy,3.0kGy,5.0kGy共5个剂量组,以研究辐照吸收剂量对降解效率的影响,同时分别对氧氟沙星水溶液进行空气饱和（水合电子清除剂）、氮气饱和、添加0.005mol/L及0.05mol/L氯化钠、添加0.05mol/L叔丁醇（羟基自由基清除剂）、添加0.005mol/L碳酸钠、添加0.005mol/L硫酸钠等方法进行处理,以探究降解过程中辐照水体产生自由基对氧氟沙星降解的贡献率.结果表明,以空气饱和进行处理,可提高氧氟沙星的降解率,辐照吸收剂量为2.0kGy时降解率可达99%.反之,加入氯化钠、叔丁醇和碳酸钠抑制了氧氟沙星的降解,加入硫酸钠则影响不大,表明羟基自由基在氧氟沙星降解中起关键作用.通过应用超高效液相色谱-质谱（UPLC-MS）对降解产物的分析鉴定,推测出了氧氟沙星的降解转化途径.     

电子束辐照降解水体中磺胺间甲氧嘧啶

应用电子束辐照初步探索了去除水体中磺胺间甲氧嘧啶（SMM）10mg/L的过程.研究了吸收剂量、自由基清除剂、无机盐等对辐照降解的影响.通过实验数据和模拟计算,推测了降解机理和降解路径,并对降解产物进行了毒性评估.结果表明,当吸收剂量为3.0kGy时,去除率高于99%,辐照降解效率高.在辐照降解过程中,还原消除占主导作用.降解反应遵循一级动力学方程.碳酸根、硫酸根和硝酸根等无机阴离子在一定的程度上会抑制SMM的降解.根据超高效液相色谱-质谱（UHPLC-MS）对降解产物的分析,结合高斯理论模拟,推断出9种可能的降解产物和相应的降解途径.费氏弧菌的毒性测试显示,辐照降解中间体毒性先升高后降低,在吸收剂量为2.0kGy达到最高值.     

活性炭负载纳米TiO2对腐殖酸光催化降解动力学

采用溶胶-凝胶法制备了以颗粒活性炭(GAC)为载体的纳米TiO2/AC复合催化剂,并将其用于腐殖酸的光催化降解.动力学研究表明,TiO2/AC光催化降解腐殖酸过程可用Langmuir-Hinshelwood(L-H)动力学模式表示.L-H表观反应速率常数KLH=0.1124mg·L-·1min-1,吸附平衡常数K*=0.3402L·mg-1.活性炭负载TiO2对腐殖酸的光催化降解过程,体现了活性炭与TiO2的协同作用,活性炭的吸附作用提高了光催化反应速率.