二氧化氯在饮用水消毒中的应用前景

本文通过二氧化氯对有机卤代物形成的影响，消毒效果，对健康的影响，以及去除水中污染物的能力和ＣｌＯ２发生技术等方面的综合评述，认为二氧化氯在饮用水消毒中的应用前景是乐观的。     

论有机污染型饮用水二氧化氯消毒

针对我国７大小系及湖泊水质日趋恶化有机污染日类重，氯消毒产生卤代甲烷等致癌物质而危害人体健康的现实，提出用ＣｌＯ２替代一般氯制剂对饮用水消毒，运用大量数据和实例，论证了用ＣｌＯ２替代一般氯制剂的必要性和可行性，并对使用ＣｌＯ２ＩＩＥ ＧＸＧＵＲ ＰＶＷＧＮ进行了论述。     

化工废水和人尿中Cl^—的测定

在Ｈ２ＳＯ４－ＨＣｌＯ４－Ｈ３ＰＯ４混酸介质中，加入标准Ｋ２Ｃｒ２Ｏ７，用ＣＣｌ４萃取，水相以标准硫酸亚铁铵滴定测定氯离子含量。     

OH自由基引发光氧化氟氯碳化合物的研究

研究了ＣＦＣ－１１＋Ｈ２Ｏ２，ＣＦＣ－１１＋Ｈ２Ｏ２＋Ｏ２，ＣＦＣ－１２＋Ｈ２Ｏ２和ＣＦＣ－１２＋Ｈ２Ｏ２＋Ｏ２４个体系的光化学反应，这些体系在低压尔照射下，Ｈ２Ｏ２产生了ＯＨ自由基，ＯＨ自由基能引发ＣＦＣ的光氧化反应，其产物在２０ｍ长的漪避用富叶红外光谱仪测量，发现在ＣＦＣ－１１＋Ｈ２Ｏ２和ＣＦＣ－１１＋Ｈ２Ｏ２＋Ｏ２体系中有ＣＯＦＣｌ，ＣＯ２和ＨＣｌ，而在ＣＦＣ－１２＋Ｈ２Ｏ２和ＣＦＣ－１２＋     

过氧化氢存在下HCFC－22光解特性

模拟大气条件研究了ＨＣＦＣ－２２＋Ｈ２Ｏ２在有氧或无氧存在下用低压汞灯进行辐照，在２０ｍ的长光程池中用富里叶红外光仪测量其化学产物，结果表明在没有氧情况下产物为ＣＯＦ２、ＣＯ２、ＨＦ和ＨＣｌ；有氧存在时产物为ＣＯ２、Ｈ２Ｏ、ＨＦ和ＨＣｌ．从这些产物推出其可能的光解机理．     

过氧化氢存在下HCFC－22光解特性

模拟大气条件研究了ＨＣＦＣ－２２＋Ｈ２Ｏ２在有氧或无氧存在下用低压相进行辐照,在２０ｍ的长光程池中用富里叶红外光仪测量其化学产物,结果表明在没有氧情况下产物为ＣＯＦ２,ＣＯ２,ＨＦ和ＨＣｌ;有氧存在时产物为ＣＯ２,Ｈ２Ｏ,ＨＦ和ＨＣｌ。从这些产物推广其可能的光解机理。     

取代芳烃对酵母菌毒性的定量结构－活性相关研究

定量测定了苯胺类、苯甲酸类、卤代苯类、苯腈类、硝基苯类、苯酚类等６类化合物对酵母菌的生长抑制毒性，结果表明化合物的最小产生清晰抑菌圈浓度Ｃ＿（ｍｉｚ）与辛醇－水分配系数及一阶分子连接性价指数有如下关系：ｌｏｇ（１／Ｃ＿（ｍｉｚ））＝０．３８ｌｏｇＫ＿（ｏｗ）＋０．３３￣１Ｘ￣ｖ－０．３８ｒ＝０．９２ｓ＝０．２２ｎ＝７７．在上述６类取代苯类化合物中，它们与酵母菌的反应性大小有如下顺序：卤代苯类≈苯甲酸类＜苯胺类＜苯腈类＜苯酚类＜硝基苯类化合物；用Ｆｒｅｅ－Ｗｉｌｓｏｎ法研究各基团对酵母菌毒性的贡献大小，其顺序为：—Ｂｒ（０．８４）＞—Ｃｌ（０．５４）＞—ＣＨ＿３（０．３９）＞—ＮＯ＿２（０．３５）＞—ＣＯＯＨ（０．１９）≈—ＯＨ（０．１７）≈—ＣＨＯ（０．１７）≈—ＣＮ（０．１４）＞—Ｆ（—０．０３）＞—ＮＨ＿２（—０．０８）．苯胺类、苯腈类、苯酚类、硝基苯类化合物对酵母菌的毒性与化合物的分子连接性指数３Ｘｖ、４Ｘ、３Ｘ有良好的相关性．     

聚合氯化铝(PAC)对腐殖酸有机溶胶混凝机理的探讨

采用一定铝总量［Ａｌ］Ｔ的不同羟铝比（ｒ＝［ＯＨ］／［Ａｌ］）的ＰＡＣ溶液对有机溶胶进行混凝实验．结果表明，聚合氯化铝表面张力（σ）与有机溶胶的ＣＯＤ去除率呈正相关．根据溶液表面张力与溶质水合能力的关系和不同羟铝比的聚合氯化铝中各种羟铝配离子的相对含量，探讨聚合氯化铝对有机溶胶的混凝机理．     

二氧化氯处理苯酚和甲醛废水的研究

本文利用化学法制备的纯ＣｌＯ２以及利用ＬＣ－１０Ａ型光激发二氧化氯复合消毒剂发生器产生的复合氧化性气体－ＣｌＯ２，Ｃｌ，Ｈ２Ｏ、Ｏ３等分别对苯酚和甲醛模拟废水进行了氧化处理。     

Fe~（2＋）－H_2O_2法处理DSD酸生产氧化母液的研究

为改善ＤＳＤ酸氧化母液的可生化降解性，将废液先用有机絮凝剂ＴＳ－１（一种季胺盐）处理，ＴＳ－１的投加量为３ｇ／Ｌ，其后用Ｆｅ２＋－Ｈ２Ｏ２法氧化，Ｆｅ２＋和Ｈ２Ｏ２的量分别为１５０ｍｇ／Ｌ，７ｇ／Ｌ，废液ＣＯＤ和色度的去除率分别可达６４％和６２％。经处理后的废水，其ＢＯＤ５／ＣＯＤ≈０．３，可以认为已达到生化处理的要求。当Ｈ２Ｏ２的投量为２ｇ／Ｌ，经Ｆｅ２＋－Ｈ２Ｏ氧化处理后的废液，再用ＦｅＣｌ３进行两级混凝处理（ＦｅＣｌ３的投加量分别为ｓｇ／Ｌ和２ｇ／Ｌ），则ＣＯＤ和色度的去除率可达９０％和９５％。     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.     

Simultaneous removal of ammonium and phosphate by zeolite synthesized from coal fly ash as influenced by acid treatment

Zeolite synthesized from fly ash （ZFA） without modification is not efficient for the purification of NH4＋ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 （≥0.9 mol/L） resulted in a limited maximum phosphate immobilization capacity （PIC）. It was concluded that through a previous mild acid treatment （e.g. 0.01 mol/L of H2SO4）, ZFA can be used in the simultaneous removal of NH4＋ and P at low concentrations simulating real effluent.