不同类型表面活性剂对1,2,4—三氯苯的增溶作用

研究了阴离子表面活性剂十二烷基硫酸钠，阳离子表面活性剂十六烷基三甲基溴化铵和非离子表面活性剂脂肪醇聚氧乙烯醚ＬＡＥ对１，２，４－三氯苯（ＴＣＢ）的增溶作用。讨论了表面活性剂类型对增溶作用的影响。比较发现，非离子型表面活性剂的增溶能力高于离子有面活性剂。其原因主要是疏水有机物在非离子表面活性剂胶束中的增溶方式不同造成的。３种表面活性剂ＴＣＢ的增溶数据还表明，增溶作用不仅在临界胶束浓度以上发生，而且在     

关于表面活性剂对水体和土壤污染的迫切问题

<正> 有人认为,表面活性剂(洗涤剂)在总环境化学化中占有重要地位。表面活性剂的生产逐年增加,在某些国家其生产增长速度甚至超过了总化学化的速度。当前表面活性剂世界年产量为6百多万吨。它们的主要品种是阴离子洗涤剂(60—65％),其次是非离子洗涤剂(约30)％。阳离子和两性洗涤剂只占5—7％。     

表面活性剂对老化土壤中PAHs的生物有效性的影响

采用聚2,6-二苯基对苯醚(poly(2,6-diphenyl-p-phenylene oxide),Tenax-TA)提取和蚯蚓(Eisenia Fetida)富集实验研究曲拉通-100(聚乙二醇辛基苯基醚,Triton X-100)、吐温-80(聚氧乙烯脱水山梨醇油酸酯,Tween-80)和羟丙基-β环糊精(HPCD)表面活性剂对老化农田土壤中多环芳烃(PAHs)可提取组分以及生物有效性的影响。结果显示,表面活性剂可以显著增加PAHs的可提取性和在蚯蚓体内的蓄积浓度;和对照相比,增加可提取性42.3%~269%,蚯蚓体内的蓄积量增加10%~340%。研究表明在使用表面活性剂进行土壤修复时老化PAHs类污染物可能重新释放到环境中并带来环境风险。     

阴-非离子表面活性剂对黑土中DDTs的洗脱研究

采用室内序批试验研究了几种非离子及阴离子表面活性剂,以单一和组合2种方式对人工污染黑土中滴滴涕(DDTs)的洗脱特性及影响因素进行了对比分析。结果表明:非离子表面活性剂对DDTs的洗脱效果优于阴离子表面活性剂,其中Tween 60和Tween 80的洗脱效果最佳,最高洗脱率达33.2%~37.2%。将Tween 60与阴离子表面活性剂SDS按一定质量比例组合可提高洗脱效果,尤其在质量比为3∶1时的洗脱率比Tween 60单独处理时高20%以上。表面活性剂对DDTs洗脱率随土壤老化时间的延长而降低,而土壤老化时间对Tween 60-SDS组合洗脱能力的抑制程度小于对Tween 60洗脱能力的抑制程度。无机助剂Na2SiO3或Na2CO3的添加可显著促进DDTs的表面活性剂洗脱效果,其中1 000mg/L的Na2SiO3使单一及混合表面活性剂对DDTs的洗脱率提高至1.4倍左右。3种有机助剂的添加同样对4,4’-DDT洗脱率起到一定的强化作用,但强化效果略低于无机助剂,对洗脱效果的促进作用大小顺序为:正丙醇正丁醇正己醇。     

塿土对阴-非离子表面活性剂的吸附特征研究

以平衡吸附法研究了塿土对阴离子表面活性剂（SDS）、非离子表面活性剂（TritonX-100、Tween80和Brij35）的吸附特征,考察了pH、阴-非离子表面活性剂混合对塿土吸附表面活性剂的影响。结果表明,非离子表面活性剂在塿土上吸附等温线均呈L型,且均符合Freundlich和Langmuir方程;塿土对SDS的吸附等温线呈LS型,可用Freundlich方程来描述;塿土对4种表面活性剂吸附量的大小顺序为Tween80〉SDS〉Brij35〉TritonX-100。当阴-非离子表面活性剂一起进入土壤中,SDS-Brij35之间的相互影响不大;TritonX-100与SDS相互作用较大,无论二者以何种方式混合都会使TritonX-100在塿土上的吸附量增加,SDS的吸附量下降;SDS与Tween80之间的相互作用最大,混合后吸附量均下降,但Tween80吸附量降低的幅度最大。pH对非离子表面活性剂的吸附影响不大,而随着pH的增加,塿土对SDS的吸附百分率明显下降;在pH为8.0时,塿土对非离子表面活性剂的吸附百分率达到80以上。因此在选择合适的表面活性剂进行有机污染土壤修复和治理时,考虑土壤的特性和表面活性剂的结构是非常重要的。     

表面活性剂在农业中的应用及对水环境的危害

表面活性剂通常分为4大类:阴离子、阳离子、非离子和两性离子型。它们被广泛应用于各行各业中,在农业中,主要和农药、化肥等配合使用,也可用于污染土壤的修复。但随着表面活性剂的使用,随之而来的是危害问题。例如壬基酚,已有大量实验证明其具有内分泌毒性、神经毒性、生殖毒性、免疫毒性和生态毒性及遗传学毒性等,其对中国林蛙96 h的50 d半致死浓度(LC50)为170μg/L,对贻贝的LC50为140μg/L。未来应加大表面活性剂安全性方面的研究,同时应研究有毒表面活性剂的高效降解与去除方式,寻找更佳的绿色表面活性剂。     

阴/非表面活性剂对菲污染砂土柱淋洗研究

采用玻璃土柱法比较研究了1000、2000、3000和4000mg·L^-1的阴离子表面活性剂十二烷基苯磺酸钠（SDBS）、非离子表面活性剂聚氧乙烯山梨糖醇酐单油酸酯（Tween80）及不同质量配比的混合表面活性剂（SDBS-Tween80）（S∶T=1∶1、1∶2和1∶4）对砂土中菲的柱淋洗。结果表明,SDBS对菲的淋洗曲线总体上呈现先上升到峰值而后下降的变化规律,且呈锯齿形波动;而Tween80与SDBS-Tween80对菲的淋洗曲线具有相似的规律,即淋出液中菲浓度随表面活性剂淋洗液孔隙体积数增大呈现急剧增大、达到峰值后逐渐降低的趋势。淋洗结束时（菲流出浓度接近于0时）,不同浓度的Tween80和SDBS-Tween80对菲的总去除率均可达90.5%以上,而4000mg·L^-1的SDBS对菲的总去除率则仅为76.4%。此外,随着Tween80或SDBS-Tween80浓度增大,菲浓度峰值增大,开始有菲淋出时,菲浓度峰值以及菲流出浓度接近于0时对应的孔隙体积数均减小。菲浓度峰值与表面活性剂浓度呈正相关,累积孔隙体积数与表面活性剂浓度呈负相关。在淋出液累计孔隙体积数相同时,同种表面活性剂对菲的去除率与表面活性剂浓度呈正相关。     

表面活性剂对东北黑土中苯并[a]芘的增溶洗脱作用

研究了4种常见表面活性剂十二烷基苯磺酸钠(SDBS)、十二烷基硫酸钠(SDS)、Tween80和TritonX-100对东北农田黑土土壤中苯并[a]芘的洗脱修复效果。增溶试验结果表明,非离子表面活性剂Tween80和TritonX-100对苯并[a]芘的增溶能力显著高于阴离子表面活性剂SDBS和SDS。4种表面活性剂在单一和混合处理条件下均能不同程度地洗脱土壤中的苯并[a]芘,且洗脱率随着表面活性剂浓度的增加而增大。各表面活性剂洗脱能力大小顺序为Tween80-SDS(3:1)Tween80-SDS(1:1)Tween80-SDS(10:1)Tween80TritonX-100SDSSDBS,当Tween80和SDS质量比为3:1时对两受试土壤中苯并[a]芘的去除率分别达到最高的42.3%和44.8%,可见阴-非离子混合表面活性剂对土壤苯并[a]芘的洗脱效果好于单一表面活性剂。土壤老化70 d后,Tween 80和Tween 80-SDS(3:1)处理对苯并[a]芘的洗脱率相比老化仅14 d的土壤分别下降了20.5%和12.9%,表明土壤老化时间的增加可降低表面活性剂对苯并[a]芘的洗脱去除效果。     

表面活性剂调控瘤胃营养功能研究进展

表面活性剂分为化学表面活性剂和生物表面活性剂两大类,非离子表面活性剂和生物表面活性剂作为新型反刍动物饲料添加剂,可通过改变瘤胃液乳化特性、瘤胃微生物种群数量、分泌酶活性、酶吸附能力和瘤胃发酵模式,来增强瘤胃微生物对粗饲料的降解能力,进而提高反刍动物生产性能。综述提出了表面活性剂在反刍动物瘤胃营养调控领域的研究重点。     

吐温类表面活性剂在黑龙江黑土中的吸附特性研究

采用平衡振荡法,研究黑龙江黑土对吐温类非离子表面活性剂(Tween20、Tween40、Tween60和Tween80)的吸附特征及影响因素。结果表明,在试验浓度范围内,吐温类表面活性剂在黑土上的吸附随着平衡质量浓度的增加而增加;各表面活性剂的吸附等温线均呈"S"型,可用Freundlich吸附模型来描述;在同一平衡质量浓度下,Tween20和Tween40在黑土中的吸附量高于Tween60和Tween80的吸附量;有机质含量高的土壤S1对表面活性剂吸附能力高于有机质含量低的土壤S2。通过H2O2氧化去除黑土中的有机质后,对表面活性剂的吸附量与原土相比变化不大,表明土壤矿物质和有机质都是吸附表面活性剂的重要成分。黑土对Tween80的吸附量随着温度的增加而增加,但随着体系pH值的增加而呈现逐渐下降的趋势。     

Acetochlor as a soil pollutant

The agricultural use of pesticides leads to diffuse pollution whereby the various contaminants of the soil infiltrate into the groundwater reaching lakes and drinking water aquifers. Due to the extensive application of these chemicals, their leaching presents a high environmental risk. Since the adsorption coefficient (K) characterizes the soil / water partitioning [1] and is also representative for leaching, the first step in understanding of the environmental fate of a pollutant is to study its adsorption properties. Weak binding to the soil constituents (low K) leads to groundwater pollution, while a strong binding (high K) results in surface water pollution through the erosion of the soil. Acetochlor is a widely used herbicide all over the world. Similar to other organic pollutants, the environmental fate of this chemical is strongly related to its adsorption properties. Static adsorption equilibrium measurements were carried out at 25°C on different types of Hungarian soils (chernozem, brown forest and sandy soil) characterized by varying amounts of organic matter and pH values. Acetochlor solutions were prepared in the presence of nitrate and phosphate ions (0.1 mol/L sodium nitrate and 0.1 mol/L phosphate uffer, pH=7) which are constituents of fertilizers occurring in high concentrations in the environment. In order to appreciate their effect, adsorption studies were also performed in pure aqueous medium. The equilibrated liquid was analyzed after centrifugation by two different methods (Total Organic Carbon measurement, High Performance Liquid Chromatography). Isotherms obtained under different conditions, as well as on various soils, exhibit a similar shape, thus indicating a two-step adsorption process. The plots cannot be interpreted according to the classes of isotherms suggested by Giles (H-, L- and C-type, [2]). The adsorption coefficients were estimated from the initial slope of the curves. These values were determined not only by the type of the soil, but also by the composition of the aqueous media. Due to the low value of the adsorption coefficients, the acetochlor is a rather mobile pollutant of the soil posing a potential danger to the aquatic environment. The organic matter adsorption coefficients (K_om) [3] were also calculated and they were approximately identical for soils of high organic matter. For the chernozem and brown forest soils, the values of the K and K_om parameters are increasing in the order from water < phosphate buffer < sodium nitrate. For soils of low organic content, the similarity of the K_om values cannot be expected (due to the hyperbolic nature of the equation) as the data really indicate it for the adsorption behavior of the sandy soil. Here, the organic matter plays a less important role and the adsorption is controlled by the solute / inorganic substance interactions. This conclusion is nicely proved by the adsorption of the acetochlor on quartz resulting thereby in a similar plot being obtained for the soils. According to the hypothesis presented here, the first step of the isotherms is controlled by the solute / surface interactions while the solute / adsorbed solute interactions are operating in the second step of the isotherm. The role of the organic matter in this region of the isotherm is probably negligible. The comparison of the adsorption coefficients leads to the conclusion that the presence of nitrate and phosphate ions enhances the adsorption of acetochlor on the soils containing a high percentage of organic matter. As these ions are present in the environment due to the extensive use of fertilizers, they may increase the acetochlor pollution of water by erosion. This conclusion corroborates those earlier observations that reported frequent acetochlor contamination of the surface waters [4–5]. As the organic matter content of the soils plays an important role in the acetochlor adsorption, humic substances must have a strong influence on the transport of this compound. Experiments to obtain adsorption isotherms of further pesticides and the development of a quantitative model are in progress.     

Adsorption of Cadmium and Zinc onto Micaceous Minerals: Effect of Siderophore Desferrioxamine B

The mobility, bioavailability, and environmental fate of heavy metals in soil are controlled by their adsorption onto soil minerals and solid organic matter. The adsorption is strongly affected by the presence of various low-molecular-weight organic acids. In this study, effect of hydroxamate siderophore desferrioxamine B (DFOB) on cadmium (Cd) and zinc (Zn) adsorption onto two micaceous clay minerals, muscovite and phlogopite, was evaluated in batch experiments. Results showed that the presence of DFOB diminished the adsorption of Cd and Zn onto both minerals, particularly under neutral to alkaline pH conditions. For instance, at pH 8.2, the presence of DFOB caused a decrease in the adsorption of Zn onto phlogopite by nearly 50%. The equilibrium adsorption of Cd and Zn was satisfactorily described using Freundlich isotherm. The adsorption isotherms showed that the affinity of Cd and Zn onto the minerals decreased in the presence of DFOB. For example, at pH 8.0, the presence of siderophore caused a decrease in the Freundlich adsorption isotherm coefficient K_F for Zn adsorption onto muscovite and phlogopite from 4.60 to 0.07 L g^-1 and from 3.56 to 0.36 L g^-1, respectively. These findings confirm the potential influence of siderophore on the fate of Cd and Zn in arid soils containing substantial contributions of micaceous silicate minerals.     

外源酚酸在杨树人工林土壤中的吸附与滞留动态研究

采集不同连作代数杨树人工林土壤样品,采用外源添加酚酸的方法结合HPLC定量测定,研究了对羟基苯甲酸和苯甲酸在杨树人工林土壤中的吸附动态和滞留规律,探讨了两种酚酸在杨树人工林土壤中的累积机制。结果表明:(1)两种酚酸在杨树人工林土壤中的吸附可大致分为两个过程,即快速吸附阶段和慢吸附阶段,对羟基苯甲酸的快速吸附阶段大约在16h内完成,而苯甲酸约需24h。达到吸附平衡时,对羟基苯甲酸在土壤中的平均吸附率为58.78%,苯甲酸的平均吸附率为37.07%。(2)杨树人工林土壤对两种酚酸均具有较强的吸附能力,达到吸附平衡时,对羟基苯甲酸在土壤中的平均吸附量为2483.19μg/g,苯甲酸为1377.51μg/g,对羟基苯甲酸的吸附能力强于苯甲酸。(3)Langmuir动力学方程和一级动力学方程是描述两种酚酸在土壤中吸附过程的最优模型。(4)酚酸滞留量检测结果表明,酚酸添加15d后,对羟基苯甲酸在土壤中的残留率为4.3%～5.2%,而苯甲酸的残留率仅为1.3%～1.7%。两种酚酸在土壤中的滞留动态可以用准二级动力学方程进行描述,对羟基苯甲酸的消除半衰期平均为4.24d,苯甲酸消除半衰期平均为2.61d,对羟基苯甲酸在土壤中的滞留期长于苯甲酸。(5)两种酚酸的吸附与滞留行为与土壤有机质、金属离子、土壤质地等性质关系密切,微生物数量也是决定酚酸在土壤中滞留能力的重要因素。     

除草剂草甘膦在几种土壤和矿物上的吸附研究

通过批平衡实验考察了草甘膦在几种性质不同土壤和矿物上的吸附行为。研究发现土壤对草甘膦有较强的吸附能力，草甘膦在土壤上吸附量的大小与土壤理化性质密切相关。草甘膦在土壤和矿物上的吸附符合Freundlich吸附方程，其在土壤上的吸附常数K与土壤粘粒含量呈正相关，并随土壤氧化铁和氧化铝含量增加而增加，而与土壤的pH呈显著负相关。草甘膦在高岭石上的吸附量要比在蒙脱石上大，而草甘膦在金属离子饱和的蒙脱石和高岭石上的吸附研究结果表明，草甘膦在钠、钙、铁离子饱和的矿物上的吸附能力依次为Fe-蒙脱石〉Ca-蒙脱石〉Na-蒙脱石和Fe-高岭石〉Ca-高岭石〉Na-高岭石。     

土壤不同粒径有机无机复合体对丁草胺的吸附特性

为了解土壤不同粒径组分对农药吸附-解吸行为的影响和吸附贡献率,以及不同粒径组分中有机无机组分的结合方式和复合程度如何影响有机质对农药的吸附,选取我国6个省区的7种理化性质差别较大的土壤,并采用物理方法提取该7种土壤的三个粒径有机无机复合体(黏粒:0.002mm;粉粒:0.02~0.002 mm;砂粒:0.05~0.02 mm)为研究材料,采用批量平衡法研究丁草胺在不同土壤和不同粒径有机无机复合体固/液界面的分配规律。同时,定量计算土壤各粒径组分对丁草胺的吸附贡献率,并从有机无机复合体角度探讨不同粒径组分中总有机碳(TOC)对丁草胺的吸附特性。结果表明:土壤黏粒组分对丁草胺具有最大的吸附量和较小的解吸率,而砂粒组分对丁草胺则具有较小的吸附量和最大的解吸率。土壤黏粒、粉粒和砂粒组分对丁草胺的吸附贡献率分别为36.7%~72.4%、21.7%~50.5%和10%。TOC是影响各粒径组分对丁草胺吸附的主要原因,但其影响程度受各粒径组分中TOC的理化性质以及其与无机矿物的复合程度控制。     

手性异丙甲草胺在土壤中的选择性降解

Separation of chiral enantiomers and the dissipation of rac-metolachlor and S-metolachlor in soil were evaluated using achiral high-performance liquid chromatography （HPLC） and chiral gas chromatography （GC） methods. Under the experimental conditions the possible metabolite was considered to be N-（2-ethyl-6-methyl-phenyl）-2-hydroxy-acetamide. Because of the presence of two chiral elements （asymmetrically substituted carbon and chiral axis）, the baseline separation of metolachlor enantiomers was not achieved. S-metolachlor degraded faster in soil than rac-metolachlor. After a 42-day incubation, 73.4% of rac-metolachlor and 90.0% of S-metolachlor were degraded. However, due to the absence of biological processes the degradation process in sterilized soil showed no enantioselectivity. The results indicated that enantioselective degradations could greatly affect the environmental fate of metolachlor and should be considered when the environmental behavior of these compounds was assessed.     

酞酸酯在土壤中的环境行为与健康风险研究进展

酞酸酯(PAEs)又称邻苯二甲酸酯,是环境激素类有机化合物,作为增塑剂在塑料、树脂和橡胶制品中的添加量一般为20%~60%。土壤中PAEs的主要来源有农用化学品、污水灌溉和大气沉降。PAEs在土壤中有较强的富集作用,并能通过一系列的环境地球化学过程进入不同的环境介质,引起环境污染和人类健康风险。本文结合国内外土壤PAEs的相关研究成果,综述了我国土壤PAEs的污染现状,分析了PAEs在土壤-大气界面(挥发、沉降)、土壤-植物系统(植物吸收、植物修复)、土壤-水界面下的环境行为(吸附-解吸)及土壤PAEs污染的环境健康风险,并指出国内土壤PAEs研究中存在的不足。研究结果显示,我国土壤环境总体上已遭受不同程度的PAEs污染;同时,土壤PAEs通过不同界面之间的迁移转化过程,也面临较高的生态环境健康风险。提出今后土壤PAEs研究应以区域土壤污染与环境行为为重点,深入研究土壤PAEs的时空传输与演变规律、多介质迁移转化机制和风险削减与修复措施,为保障土壤生态环境与健康提供理论依据。     

Estimation of buffering capacity of mangrove soils by using hydrophobic organic compounds,atrazine and linuron

Samples of two soils and two sediments collected at sites originating from mangrove forests in Thailand, were examined in terms of buffering capacity to organic compounds. Atrazine and linuron were used as representative hydrophobic organic compounds for estimating the buffering capacity by observing their adsorptive and desorptive behavior. The buffering capacity could be represented by the distribution of the adsorption ratio (AR) and desorption ratio (DR) as follows: AR (%) = (amount of herbicide adsorbed per unit weight of soil)/(initial amount of herbicide) x 100, and DR (%) = (amount of herbicide desorbed per unit weight of soil after herbicide desorption experiments) / (initial amount of adsorbed herbicide on soil) x 100. The soil under mangrove forests displayed a larger buffering capacity to atrazine and linuron. Compared with 42 soils from Japan, in terms of the adsorption proparty of atrazine and linuron, the mangrove soil ranked in a higher category on the classification of the Japanese soils. Thus, the importance of maintaining or recovering the mangrove forests to promote environmental conservation was emphasized.     

离子强度和三氧化物对土壤吸附Bt毒素的影响

Chemical reactions and fate of the toxins of Bacillus thuringiensis(Bt) in the soil environment are causing increasing concerns due to the large-scale cultivation of transgenic Bt plants.In this study,the effect of ionic strength(0-1 000 mmol kg 1) adjusted by NaCl or CaCl 2 on adsorption of Bt toxin by a lateritic red soil,a paddy soil and these soils after chemical removal of organic-bound or free Fe and Al oxides,as well as by pure minerals(goethite,hematite and gibbsite) which are widespread in these soils,were studied.The results indicated that when the supporting electrolyte was NaCl,the adsorption of Bt toxin by the lateritic red soil and paddy soil increased rapidly until the ionic strength reached 250 mmol kg 1 and then gradually slowed down with the increase of ionic strength;while in case the supporting electrolyte was CaCl 2,the adsorption of Bt toxin enhanced significantly at low ionic strength(< 10 mmol kg 1) and then decreased as the ionic strength increased.The adsorption of Bt toxin by the tested minerals and soils after the removal of organic-bound or free Fe and Al oxides also increased with increasing ionic strength controlled by NaCl.Removing organic-bound Fe and Al oxides obviously increased the adsorption of Bt toxin in the tested soils.Differently,removing free Fe and Al oxides increased the Bt adsorption by the paddy soil,but decreased the adsorption by the lateritic red soil.The study indicated that the varieties of ionic strength and the presence of Fe and Al oxides affected the adsorption of Bt toxin by the soils,which would contribute to the further understanding of the fate of Bt toxin in the soil environment and provide references for the ecological risk assessment of transgenic Bt plants.     

Insecticide Residues in Eggplant Fruits, Soil, and Water in the Largest Eggplant-Producing Area in the Philippines

A multiphase model based on the Mackay-type level II fugacity model has been used to predict the behaviour and final environmental concentrations of some of the more consumed pharmaceuticals in Spain. The model takes into account the mean rate of consumption of pharmaceuticals, the percentage of pharmaceutical metabolised, the formation of the corresponding glucuronide, which is assumed to be hydrolysed back to the parent molecule, the partial degradation of each pharmaceutical in a conventional sewage treatment plant, and the fate of these substances in a regional model environmental system. Predicted environmental concentrations in air, water, soil, sediments and suspended matter, and the corresponding residence time for each pharmaceutical have been obtained by application of the model. The predicted concentrations of pharmaceuticals in the water phase are of the same order than the measured experimentally, showing that the simple model used to predict the environmental concentrations is suitable for modelling the environmental fate of high water soluble and low volatile organic compounds such as pharmaceuticals products.