表面活性剂和硫酸盐还原菌去除污染土壤中的Cr6+

用表面活性剂和硫酸盐还原菌(SRB)淋洗Cr污染土壤,采用欧洲共同体参考物机构连续提取法分析淋洗前后土壤中铬化学形态和相对含量的变化. 结果表明,阴离子表面活性剂十二烷基苯磺酸钠和非离子表面活性剂Tween-80浓度分别为5.0, 0.01 g/L时,对土壤中Cr的淋洗效果最好,当土壤中Cr含量为200 mg/kg时,淋洗率分别为14.70%和24.74%,500 mg/kg时,淋洗率为35.99%和41.42%;反应体系中菌液量为10 mL时,淋洗18 h上清液中Cr6+转化率最大,分别为98.07%和94.73%;用表面活性剂和SRB共同处理Cr污染土壤,上清液中Cr6+可全部转化为Cr3+,未被淋洗出的Cr从较易被植物利用的可交换态转化为稳定态,主要以Cr2(CO3)3和Cr(OH)3存在于土壤中,达到了土壤环境质量标准.     

The Use of Reverse Osmosis in the Removal of PAHs from Municipal Landfill Leachate

Polycyclic aromatic hydrocarbons (PAHs) are relatively well-known organic pollutants and due to their carcinogenic and mutagenic properties their presence in the environment still attracts a lot of attention.

According to literature reports and own research, PAHs presence in wastewaters is common. It was confirmed that PAHs are the components of municipal landfill leachate. Membrane techniques are one of the most interesting ways of removing PAHs from leachate.

The purpose of this article is to monitor PAHs concentration changes during the membrane (reverse osmosis - RO) leachate treatment processes. In the first stage of testing leachates were filtrated on the sand bed (pre-filtration). After the pre-filtration they were directed to the membrane module for the main filtration.

Sixteen PAHs listed by EPA were analyzed. The results with information on PAHs concentration in leachate samples were presented using HPLC with fluorescence detection (FLD). The changes in PAHs concentration were determined in leachate samples before and after pre-filtration as well as after RO. The decrease of PAHs concentration in the samples was observed after these processes. The total concentration of 16 PAHs in raw municipal landfill leachates amounted to 23.64–26.95 μg/L. The research confirmed the high efficiency in removal of PAHs while using a reverse osmosis (59–72%). Including the pre-filtration, the overall level of removed PAHs reached 81–86%. The average PAHs concentration after pre-filtration and RO was in the 4.46–4.99 μg/L range. The municipal landfill leachate with a high concentration of PAHs should be cleaned before it is discharged into the environment.     

表面活性剂在农业节水中的应用

介绍了干旱问题对于我国农业生产的影响, 以及为此而开展的有关节水保墒的科学研究, 并介绍了表面活性剂在这一领域中的应用     

Laundry Detergency of Solid Non-particulate Soil or Waxy Solids: Part I. Relation to Oily Soil Removal Above the Melting Point

In this work, methyl palmitate or palmitic acid methyl ester, a monoglyceride, was used as both a model solid fat below the melting point and as an oily soil above the melting point. An anionic extended surfactant [branched alcohol propoxylate sulfate sodium salt (C₁₂₃‐(PO)₄‐SO₄Na)] was used to remove methyl palmitate from cotton and from polyester. Above the melting point (~30 °C) of methyl palmitate, the maximum oily soil removal was found to correspond to the lowest dynamic interfacial tension, as is common with liquid soils. Below the melting point, the lower the contact angle of the wash solution against the soil (indicating higher wettability), the higher the solid fat soil detergency. The removed methyl palmitate was found to be mostly in unsolubilized droplets or particles with a small fraction of micellar solubilization for both solid and liquid forms. The presence of surfactant can prevent the agglomeration of detached methyl palmitate particles in both liquid and solid forms, reducing redeposition and enhancing detergency. Below the melting point, the surfactant aids the solution wetting the surfaces, then penetrating the waxy solid, causing detachment as small particles, and dispersion of these particles. Unlike particulate soil detergency, electrostatic forces are not the dominant factor in fatty soil detergency.     

生物表面活性剂强化降解土壤中PAHs研究进展

从生物降解有机污染物多环芳烃(PAHs)的限制因素入手,介绍了生物表面活性剂(BS)强化生物降解效果的研究进展。总结了近年来代表性成果,解释BS对生物降解过程强化作用机理,包括增溶作用、增加细胞吸附PAHs、促进微生物摄取PAHs等;讨论了BS的生物毒性、生物降解性和吸附性对降解过程的抑制效果。分析出强化效果受多污染物相互作用、环境因子、BS体系、土壤构成等因素影响。但值得关注的是这些科学研究大多只在实验室规模上进行,应用到场地修复之前仍需要许多改进。场地修复时使用合理复配体系可提高去除效率,非常具有应用前景。     

表面活性剂对苄嘧磺隆和丁草胺在土壤中吸附的影响

采用批量平衡吸附法测定了苄嘧磺隆和丁草胺在北碚土、郑州土、彭水土中的吸附常数Kd,并通过添加阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)和阴离子表面活性剂十二烷基苯磺酸钠(SDBS)改变了其在土壤中的吸附常数。结果表明,苄嘧磺隆和丁草胺在土壤中的吸附过程均符合Freundlich模型,在3种土壤中的吸附均表现为:北碚土>彭水土>郑州土。随着CTAB浓度的增加,2种农药的Kd值显著增加;随着SDBS浓度的增加,2种农药的Kd值呈先降低后增加的趋势。     

土壤多环芳烃的生物修复研究

多环芳烃(polycyclic aromatic hydrocarbons,PAHs)是环境中普遍存在的具有代表性的一类重要持久性有机污染物,具"三致性"、难降解性,在土壤环境中不断积累,严重危害着土壤的生产和生态功能、农产品质量和人类健康。修复土壤多环芳烃污染已成为研究的焦点。生物修复技术因具有成本低、无二次污染、可大面积应用等独特优点而越来越受到人们的重视,是目前最具潜力的土壤修复技术之一。     

Use of surfactants and blends to remove DDT from contaminated soils

Removal of dichloro‐diphenyl‐trichloroethane (DDT) from soils using surfactant‐enhanced solubilisation was studied both in batch and continuous flow arrangements to determine if there were advantages to using a combination of non‐ionic (Tween and Brij) and anionic surfactants. It was observed that the presence of the anionic surfactant sodium dodecyl benzene sulphonate improved the DDT removal efficiency, but had a potentially negative effect on flow rates in column leaching experiments at concentrations over 0.1%. The potential for re‐use of the surfactant mixture was studied and demonstrated by removing DDT and its metabolites from the surfactant solution using activated carbon. © 2011 Canadian Society for Chemical Engineering     

改进索氏提取器提取土壤中多环芳烃（菲、蒽、屈）

文章用改进索氏提取器与自动索氏提取器提取土壤中加标多环芳烃（菲、蒽、屈）,采用高效液相色谱法对提取液进行分离测定,并选择了流动相最佳比例。结果表明,采用改进索氏提取器,二氯甲烷作提取剂,氧化铝柱层析法纯化,并用HPLC—UVD测定可得到很好的效果。三种多环芳烃的平均加标回收率在78.7%~111%之间,且重现性较好。     

微生物作用下多环芳烃在土壤中的迁移特征

以菲、蒽和芘为研究对象,通过淋溶实验考察抑菌和未抑菌条件下三者在土壤中的迁移过程,结果表明,微生物的存在抑制PAHs淋出:抑菌条件下180 d时菲、蒽和芘的淋出率分别为8.74%、28.53%和13.56%,未抑菌条件下240 d时菲、蒽和芘的淋出率分别为0.95%、1.47%和0.37%。抑菌和未抑菌条件下3种PAHs均易吸附于表层土壤中:淋滤240 d时,约75%的菲分布在进水端0~2 cm;超过90%的蒽分布在进水端10 cm以内;85%的芘分布在4 cm以内;微生物通过阻滞作用和降解作用影响PAHs的迁移,菲、蒽和芘在土壤中都能被土著微生物降解;60 d以前土柱中PAHs降解以好氧降解为主,60 d以后,PAHs的生物降解转为厌氧降解。     

表面活性剂对微生物脱除柴油中有机硫的影响

采用假单胞菌(Pseudomonas delafieldii)菌株R-8和红色红球菌(Rhodococcus erythropolis)菌株N1-36研究了加氢精制柴油脱硫工艺，两株菌脱除柴油中有机硫的活性相近. 添加表面活性剂能提高菌株对柴油的脱硫率；当Tween80存在、搅拌转速为250 r/min时，菌株R-8最高可脱除硫含量<300 mg/L的柴油中72%的有机硫；但当硫含量超过1000 mg/L时，微生物脱硫率极低.     

The Effectiveness in the Removal of PAHs from Aqueous Solutions in Physical and Chemical Processes: A Review

Polycyclic aromatic hydrocarbons (PAHs) are relatively well-known organic pollutants and due to their carcinogenic and mutagenic properties, their presence in the aqueous environment still attracts a lot of attention. This article presents a critical review of the literature on the application of physical and chemical processes for removal of PAHs from aqueous solution, including water and wastewater. The effectiveness of coagulation, chemical oxidation, photodegradation, sorption, and membrane processes in the degradation or removal of these micropollutants is described. The PAHs removal efficiency (coagulation ～ 99%, chemical oxidation ～ 87%, photodegradation ～ 93%, sorption ～ 100%, and membrane ～ 100%) during the above processes is difficult to compare due to the works conducted under different conditions and using various mediums, e.g., water, wastewater, PAHs model aqueous solutions.     

两性表面活性剂 (一)两性表面活性剂概述

介绍了两性表面活性剂的基本情况 ,诸如两性表面活性剂的定义、分类、命名法则 ,并对两性表面活性剂的国内外发展概况作了简要介绍。简要讨论了两性表面活性剂特有的等电点现象和三种典型的等电点行为。对两性表面活性剂的溶解特性特别是KP温度也进行了讨论。     

Determination of PAHs in Combustion-Related Samples and in SRM 1597, Complex Mixture of PAHs from Coal Tar

Three types of combustion sample extracts, smokeless coal, smoky coal, and wood, were analyzed for a range of polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASH). Standard Reference Material (SRM) 1597, Complex Mixture of PAHs from Coal Tar, was also analyzed as a control sample and for the determination of a larger number of PAHs relative to those determined previously. Target analytes included many alkyl-substituted PAHs such as dimethylphenanthrenes, methylfluoranthenes, and methylpyrenes. The analytical methods included sample clean-up and the selection of specific stationary phases to accomplish unique separations of PAHs. Clean-up involved the use of normal-phase liquid chromatographic isolation of PAHs based on the number of aromatic carbons and a total PAH fraction, PAHs in the resulting fractions were separated by gas chromatography using two stationary phases with different selectivities and analyzed using mass spectrometry. These methods are discussed below and results are presented with an emphasis on the relative concentrations and distribution of PAHs in the combustion samples.     

表面活性剂在造纸工业中的应用

表面活性剂是造纸化学品的重要组成部分 ,综述了国内外造纸化学品的发展概况及表面活性剂在造纸制浆、湿部、表面施胶和涂布加工等过程中的重要应用。     

土壤酸化及酸性土壤调理剂应用概述

土壤酸化不仅会加剧土壤营养元素的淋溶和固定、促进有毒元素的释放和活化,而且会影响土壤微生物的生命活动、增加环境压力。概述了我国土壤酸化的现状及原因,针对性地提出了施用石灰类、硼泥类、精制有机肥类等酸性土壤调理剂改良治理土壤酸化的措施。     

Release of PAHs Through Runoff from the Gwangan Bridge to the Coast in Busan,Korea

This study was carried out from the Gwangan Bridge in Busan, Korea in order to examine the characteristics and the amount of PAHs in runoff from Gwangan Bridge, and the consequential PAH burdens in the ocean. The runoff samples were collected in particulate and dissolved phase, and the ambient air samples were collected in particulate and gaseous phase. In this study, 20 samples were collected from 10 different sites. The concentrations of 16 PAHs, in particulate road surface samples, ranged from 76.71 to 170.98 ng/g, and the dissolved road surface runoff samples ranged from 23.31 to 72.9 ng/L. In ambient air, the PAHs concentration in gaseous phase was higher than the samples in particulate phase. From these results, the amount of annual release of PAHs through runoff into the coast was calculated, and the Toxic Potency Equivalency Factors and Dioxin Toxic Equivalency Factors were applied. The annual release of total PAHs and the carcinogenic PAHs via runoff from Gwangan Bridge to the coast were 14.1 g/yr and 3.13 g/yr, respectively. The PAHs-_TPEQ was 0.85 g/yr and the PAH-_{dioxin TEQ} was 0.69 mg/yr.     

聚硅氧烷聚醚表面活性剂在化妆品中的应用

主要介绍了聚硅氧烷聚醚表面活性剂的种类、结构、性质及在化妆品中的应用。     

The Impact of PAHs Contamination on the Physicochemical Properties and Microbiological Activity of Industrial Soils

The aim of this article is the study of the potential relationships between PAHs contamination, physicochemical parameters, and microbial activity in industrial soils. The research was based on two series of measurements. The first was conducted in June 2013 and the second in November 2013. Samples used in study were collected from the area of fuel handling and a loading station, located in the Silesia region of Poland. All collected samples were characterized by the following analytical procedures: PAHs content analysis, the basic physical and chemical parameters determinations (pH, CEC, humic acids content, TC, TN, TP) and microbial activity analysis. The obtained results were also subjected to statistical analysis, based on the Pearson's correlation coefficient calculations.

Results collected during described above procedure show that: the PAHs content was highly positively correlated with C and N contents (p < 0.001) and moderately correlated with humic acids and P contents (p < 0.01). This phenomenon confirms the thesis that the increase of soil organic matter content promotes accumulation of hydrophobic organic compounds such as PAHs. Microbiological analysis shows that bacteria from the mesophilic group are most resistant to PAHs contamination. This information indicates that the organisms belonging to this group should be considered as potentially useful in the soil bioremediation processes.