表面活性剂的结构与生物降解性的关系

对表面活性剂的生物降解性进行了全面的概述，着重讨论了表面活性剂的降解性能与结构的关系。表面活性剂的生物降解性主要由疏水基团决定，并随着疏水基线性程度的增加而增加，末端季碳原子会显著降低降解度，疏水链长短也影响降解性；表面活性剂的亲水基性质对生物降解度有次要的影响；乙氧基链长影响非离子表面活性剂的生物降解性；增加磺酸基和疏水基末端之间的距离，烷基苯磺酸盐的初级生物降解度增加（距离原则）。最后指出了我国今后表面活性剂生物降解度研究的发展方向。     

表面活性剂降解研究进展

简述了表面活性剂对环境的影响及其降解的发展概况，着重讨论了表面活性剂的各种生物降解的研究方法和特点，降解动力学，结构与降解性能间的关系，影响降解的环境因素及直链烷基苯磺酸盐（LAS），烷基硫酸盐（AS）等几类常见表面活性剂的生物降解机理。并对近年发展起来的表面活性剂光催化降解的研究方法，降解机理及降解动力学作了简要介绍。     

表面活性剂生物降解的标准与法规

表面活性剂对环境的影响引起了各国和地区的关注，纷纷建立标准与法规，引导表面活性剂向着正确的方向发展。表面活性剂对环境的影响主要表现为其生物降解性。简要概述了各组织建立的表面活性剂生物降解测试方法、降解性能要求及各国为表面活性剂建立的一些法规。阐述了我国表面活性剂生物降解标准的现状及发展趋势。     

几种阴离子表面活性剂生物降解性评价

采用BOD5/COD来评价阴离子表面活性剂的生物降解性,研究了接种物预处理方法、来源、接种量对阴离子表面活性剂生物降解性的影响,优化了降解条件,比较了常见阴离子表面活性剂的生物降解性。结果表明,LAS、AES、MES的生物降解顺序为MESAESLAS,28天生物降解率分别为MES 84%、AES70%、LAS 66%,28天生物降解率达到了OECD 301F大于60%的要求。     

油溶性表面活性剂生物降解度的测定

对ISO 10634-1995“水质———水介质中用于难溶有机物生物降解性能评价水溶液的制备与处理指南”推荐的方法进行逐一筛选,以期建立油溶性表面活性剂生物降解度测定的标准方法。实验结果表明,将油溶性表面活性剂超声乳化后,制备成粒径200 nm~300 nm乳液后,立即分散于水体系中进行降解,结果重复性较好,并且不影响油溶性表面活性剂生物降解度。用该方法对常见的油溶性表面活性剂的生物降解度进行了测定,结果表明大部分油溶性表面活性剂具有很好的生物降解性能;其降解规律与水溶性表面活性剂类似,疏水链长决定油溶性表面活性剂的生物降解性能,而亲水基团影响其生物降解速度。     

表面活性剂生物降解性能的研究进展

对表面活性剂的生物降解性能进行了全面概述。着重讨论了表面活性剂的降解性能测试方法、生物降解机理、降解动力学及用于量化分析可生物降解的同位素标记反应运移模型,并对各类表面活性剂结构与降解能力作了评价。最后,指出了我国表面活性剂生物降解度研究的发展方向。     

半连续活性污泥法测定表面活性剂的好氧生物降解度

用半连续活性污泥(SCAS)法测定表面活性剂的生物降解度,考察了表面活性剂分子在活性污泥体系中的吸附-脱附作用所导致的假降解现象,研究了活性污泥浓度对降解性能的影响,并用SCAS法对AEO7、L-64、LAS和AES进行了初级和最终生物降解度的测定,结果表明以上4种表面活性剂的初级生物降解度均>90%、最终生物降解度均>70%,达到了欧盟洗涤剂法规的相关标准,均属易降解表面活性剂。     

表面活性剂的绿色化及研究进展

简述了表面活性剂对环境的影响及研究进展。着重讨论了表面活性剂的研究方法及表征,各种生物降解过程、降解机理和影响表面活性剂生物降解的因素。并对表面活性剂的安全性及毒性、温和性及对皮肤和黏膜的刺激性进行了简要介绍。     

表面活性剂生物降解和光降解技术研究进展

表面活性剂的生物降解和光降解技术正受到越来越多的关注。介绍了该两项技术在国内外的研究现状；讨论了表面活性剂生物降解和光降解的研究成果；并对近几年发展起来的表面活性剂光催化降解的催化剂、工艺组合作了简要介绍。提出了表面活性剂生物降解和光降解的今后研究方向。     

脂肪醇聚氧乙烯醚硫酸盐生物降解和环境安全性评价

表面活性剂对环境的影响主要表现在生物降解性。简要概述了目前大量使用的表面活性剂脂肪醇聚氧乙烯醚硫酸盐（AES）的厌氧、好氧生物降解以及降解途径。阐述了AES在生物机体中的积累对环境、人体和动物的影响,表明AES在给人类生活和工业发展带来帮助的同时,不会对环境和人体健康造成危害。     

Biodegradation of different carboxylate types of cleavable surfactants bearing a 1,3-dioxolane ring

The biodegradability of new carboxylate types of “acid-sensitive” cleavable surfactants bearing a 1,3-dioxolane ring was measured by the biochemical oxygen demand (BOD) method in the presence of activated sludge. The result for sodium dodecanoate, measured under the same conditions, was used as a standard for evaluating the biodegradability of these cleavable surfactants. For cleavable surfactants derived from epoxides and oxocarboxylates, the biodegradation was considerably influenced by the length of the lipophilic alkyl chain, the presence of the oxymethyl moiety in the lipophilic group, and the number of methylene units between the dioxolane ring and the carboxylate group. For another type of cleavable surfactant, 2-(long-chain alkyl)-1,3-dioxolane-4,5-dicarboxylate, the biodegradation rate for the compound, bearing a proton at position 2 in the dioxolane ring, is faster than that for the corresponding compound bearing a methyl group at position 2.     

表面活性剂厌氧生物降解研究进展

对表面活性剂生物降解进行了全面概述,包括表面活性剂生物降解的概念和分类,表面活性剂厌氧生物降解试验方法和分析方法,最后对常见表面活性剂的厌氧生物降解性能进行了介绍。     

Primary aerobic biodegradation of cationic and amphoteric surfactants

The primary aerobic biodegradation of several cationic and amphoteric surfactants has been studied by using the shaking-flask degradation test and orange II spectrophotometric analysis. The results show that cationic and amphoteric surfactants can be readily biodegraded, with their degradation exceeding 94%. The degradation kinetics can be accurately described by the Boltzmann model. The relationship between structure and biodegradability is discussed. The presence of hydrophobic groups has a strong effect on the biodegradability of these surfactants. Biodegradability decreases with increasing chain length. The presence of hydrophilic groups mainly affects the degradation rate of these surfactants, but not their ultimate biodegradeability. Bio-degradability is deterred and degradation is slowed as steric hindrance increases. Degradation rates increase markedly when hydrophilic groups containing an amide bond are pres-ent.     

Research on Primary Biodegradation of Alkyl Ethoxy Glucoside

This investigation was performed to determine the anaerobic biodegradation of alkyl ethoxy glucoside (AEG) nonionic surfactants using the OECD 311 method. The influence of different initial concentrations of AEG on the primary biodegradation rate was investigated using the anthrone analysis method. The results show that different initial concentrations have similar good biodegradability and the biodegradation rate can reach more than 90 % even at the highest initial concentration of 100 mg/l. Alkyl polyglucoside (APG) surfactants have previously been confirmed as readily biodegradable. The profile of concentration changes over the incubation time of AEG and APG had similar trends. Therefore, AEG are also considered as readily biodegradable. The gas chromatograph‐mass spectrometer analytical method was used to identify the metabolites. The content of alcohol ethoxylate (AEO) increased with decrease in the number of AEG at the initial stage of degradation. It was found that AEO with longer EO chains disappeared first. Accordingly, a degradation pathway that accounts for the experiment results was proposed.     

Environmental Impact of Ether Carboxylic Derivative Surfactants

The ultimate aerobic biodegradability and toxicity of three ether carboxylic derivative surfactants having different alkyl chains and degrees of ethoxylation were investigated. Ultimate aerobic biodegradability was screened by means of dissolved organic carbon determinations at different initial surfactant concentrations. For comparison, the characteristic parameters of the biodegradation process, such as half-life, mean biodegradation rate, and residual surfactant concentration, were determined. Increased surfactant concentrations decreased mineralization and lengthened the estimated half-life. The results demonstrate that the ultimate aerobic biodegradability is higher for the surfactants with the shortest alkyl chain and highest degree of ethoxylation. Toxicity values of the surfactants, and their binary mixtures, were determined using three test organisms, the freshwater crustacea Daphnia magna, the luminescent bacterium Vibrio fischeri and the microalgae Selenastrum capricornutum. The toxicity is lower for the surfactants with the shortest alkyl chain and highest degree of ethoxylation. The toxicity of binary mixtures of the three ether carboxylate surfactants at a 1:1 weight ratio was also measured. The least toxic mixture is formed by the surfactants having lower individual toxicity.     

Integrated process for hydrophobic VOC treatment—solvent choice

A process coupling absorption of a gaseous pollutant in an organic phase and biodegradation was considered to treat hydrophobic volatile organic compounds (VOC). The purpose of this work was to choose the best solvent for the absorption of some VOC (dimethylsulfide, dimethyldisulfide, and toluene) and to examine solvent biodegradability as well as VOC biodegradation by activated sludge. Some experiments were carried out on some selected solvents leading to select di‐2‐ethylhexyl‐adipate (DEHA) and poly‐di‐methyl‐siloxane (PDMS) for their high absorption capacity. Biodegradation experiments showed that toluene and DMDS can be removed in solvent on water emulsions, while DMS removal by biodegradation remains to confirm owing to its high volatility. However, experiments showed DEHA biodegradation, contrarily to PDMS which was therefore selected for subsequent experiments.