Estimation of surface area of montmorillonite by ethylene oxide chain adsorption

This study investigates the feasibility of using ethylene oxide chain adsorption to determine the surface area of an expandable clay, montmorillonite. Experimental results indicate that high molecular weight poly(ethylene oxide) or nonionic surfactant with long ethylene oxide chain should be used to provide reasonable estimations for monolayer capacity. The method has advantages over Brunauer, Emmett, and Teller method in that it is readily applicable to a wide range of areas, particularly to 2:1 layer silicates under aqueous conditions.     

DO和pH值在短程硝化中的作用

在SBR反应器中对DO和pH值在短程硝化和半亚硝化过程中的作用进行试验研究,结果表明,控制低DO和适宜的pH值在短程硝化过程中起着重要的作用.本试验条件下,当DO为0.5～1.0 mg/L、pH值为7.5～8.0时,在SBR反应器中很容易实现短程硝化;当DO＞0.3 mg/L时,DO越低,出水NO2--N积累率越高;当pH值＞6.8时,不会影响系统NO2--N积累的稳定性.另外,研究结果还表明,通过控制DO和pH值可以实现半亚硝化.本试验条件下,当进水氨氮浓度为120 mg/L时,控制DO为0.3～0.4 mg/L可实现出水半亚硝化;当进水氨氮浓度为200 mg/L时,控制DO为0.5～0.6 mg/L或pH值为6.8也可以实现出水半亚硝化.     

活性炭纤维吸附废水中对硝基苯酚及其脱附研究

采用新型高效吸附剂——活性炭纤维吸附废水中对硝基苯酚，对其吸附和脱附影响因素进行了较详细的研究，确定了最佳工艺参数，并对动态吸附一脱附进行了稳定性实验。在最佳的吸附条件下，装填4g活性炭纤维可处理含对硝基苯酚1000mg/L的废水1400mL，出水对硝基苯酚浓度〈2mg／L，达到国家综合污水一级排放标准，活性炭纤维有效吸附量可达349．87mg／g。在最佳脱附条件下，脱附率〉99％，并可从高浓度脱附液中回收对硝基苯酚。稳定性实验表明，吸附-脱附性能稳定，采用活性炭纤维吸附处理对硝基苯酚废水是一种行之有效的处理方法。     

Attempt to adsorb N-nitrosamines in solution by use of zeolites

The strong adsorption of zeolite for N-nitrosamines in solution was first revealed by use of adsorption, and temperature programmed surface reaction (TPSR) techniques. N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) as well as N-nitrosohexamethyleneimine (NHMI) can be adsorbed on zeolite Y, ZSM-5 and A in the solution of methylene chloride or water, which will be helpful for removal of the N-nitrosamines pollution in environmental protection. The equilibrium data were fitted to Freundlich-type isotherms, but the adsorption capacity of zeolites mainly depended on their pore size, surface area and acid-basic properties. Molecular size of adsorbate and solute-solvent interaction also strongly affected the adsorption of N-nitrosamines on zeolite in solution. The extraordinary adsorption properties of NaA zeolite for N-nitrosamines in aqueous solution is first reported and discussed.     

新型混凝剂在废水处理中的应用研究

自行研发出一种新型混凝剂，它能广泛应用于印染废水、生活污水和餐饮废水等的处理。经过一步强化混凝处理后，各种废水的COD、色度和浊度等均有良好的去除效果。混凝污泥可以再生重复利用。     

Sample purification for analysis of organochlorine pesticides in sediment and fish muscle

The methods of sample purification for determinations of organochlorine pesticides (OCPs) in sediment and fish muscle were investigated in this study. A two-step procedure with preliminary cleanup and florisil column fraction was adopted. The working conditions of florisil column were firstly optimized. As to preliminary cleanup, liquid-liquid extraction by mixture of dimethyl formamide (DMF) and hexane and sulphonation by concentrated sulfuric acid were applied respectively and compared for the studied samples. The results indicated that liquid-liquid distribution could effectively separate lipids from fish muscle extracts, while failed in elimination of chlorophyll extracted from the relicts of hydrophytes in the sediment sample. In view of the sample appearance and clarity of gas chromatogram, sulphonation was more suitable to purify the sediment sample, however, the recoveries of the spiked standards were poor. The use of eluting solvent with stronger polarity could improve the corresponding recoveries significantly. Due to complete loss of Dieldrin, Endrin, and Endrin aldehyde after sulphonation, this pretreatment was improper to the three components. Sulfur, as the particular disturbing element in sediment, could be removed sufficiently by addition of activated copper powder. The relevant detection limits of the selected methods for OCPs in the studied substrates were also provided.     

催化湿式氧化中负载型催化剂的稳定性与应用

催化剂在应用过程中必须具有良好的催化活性和稳定性.优化制备的CuO/γ-Al2O3催化剂用于处理高浓度难降解的乳化液废水时具有良好的催化活性,在200℃时反应2 h,TOC去除率为81.3%,比未加催化剂的湿式氧化提高了14.9%.该催化剂对分散兰废水具有更高的活性和稳定性:在220℃反应1.5 h后,COD和TOC去除率分别为68.8%和56.5%,比非催化氧化分别提高了18.7%和18.9%.     

Study on the cytotoxicity of microcystin-LR on cultured cells

The toxicity of purified blue-green algal toxin, microcystin-LR, on permanent cell lines KB, NIH/3T3, H-4-II-E, HeLa, Vero, Hep G2, Caco-2 and HL-60 was studied. Assessment of cell viability using colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays indicated that purified microcystin-LR induced toxic effect on KB and H-4-II-E cell lines after 96 h incubation at toxin concentrations greater than 18.75 microg/ml. KB cell line was selected for further study when reproducibility, consistency and sensitivity were considered. Significant amounts of lactate dehydrogenase (LDH) were released from KB cells when incubation durations were 72 and 96 h with toxin concentrations of 18.75 microg/ml and higher. Although previous studies suggested that microcystin-LR had no cytotoxic effect on permanent cell lines, LDH release assay performed on KB cells indicated that exposure to microcystin-LR could result in damage to the cell membrane.     

一种新型烟气脱硫技术在燃煤锅炉上的扩大试验

介绍了用硫化碱加TFS添加剂进行燃煤锅炉煤气脱硫并副产硫代硫酸钠的中试成果。     

臭氧-曝气生物滤池处理酸性玫瑰红染料废水

在实验室配制含酸性玫瑰红染料的印染废水，采用臭氧氧化-曝气生物滤池工艺开展处理试验。试验运行结果表明，臭氧氧化处理能提高模拟废水的可生化性，BOD／COD值由原水的0．18上升到0．36。经组合工艺处理后出水COD〈40mg／L，色度40倍以下，SS约50mg／L，处理效果良好。