Biodegradation of some tallow-based surface active agents in river water

Thirty-three anionic and six nonionic detergents have been screened for biodegradability using the river water “Die Away” test. Concentrations of nonionic detergents were best determined by the surface tension method. All fat-derived compounds without mid chain substitution were found to degrade in Schuylkill River water at 20C in less than a week. Presented at the AOCS Meeting in Minneapolis, 1963. E. Utiliz. Res. and Dev. Div., ARS, USDA.     

Analysis for sulfate ion in the biodegradation of anionic detergents

A turbidimetric method is described for determining sulfate ion in parts per million formed during the biodegradation of surface-active organic sulfates or sulfonates. The procedure involves the precipitation of barium sulfate under controlled conditions, using a reagent consisting of 0.5% gelatin and 1% barium chloride in 50% ethanol. Gelatin stabilizes the barium sulfate suspension and helps prevent the formation of turbidity from barium chloride and detergent. Ethanol destroys any protective colloid action that may inhibit the precipitation of barium sulfate. Corrections were necessary for turbidity caused by the microorganisms and in a few instances for turbidity caused by the reaction of detergent and barium chloride. Absorbance was read against a blank at 420 mμ using 5 cm cells. Parts per million sulfate were read from a standard curve. Phosphates do not interfere in the determination. Presented at the AOCS Meeting, Chicago, October 1967. E. Utiliz. Ees. Dev. Div., ARS, USDA.     

饮用水中阴离子合成洗涤剂去除的研究

采用紫外-过氧化氢高级氧化联用工艺去除饮用水中低含量阴离子合成洗涤剂。在原水的十二烷基苯磺酸钠的质量浓度为1mg/L左右、紫外光强133.9μW/cm2、过氧化氢投加量20mg/L和停留时间60min条件下,十二烷基苯磺酸钠的去除效率达到90.03%;试验建立了紫外-过氧化氢光激发氧化降解饮用水中阴离子合成洗涤剂的动力学方程式;并采用正交试验,考察了动态连续流条件下不同因素对本工艺的处理效果的影响程度,分析得出各因素对本工艺处理效果影响程度的顺序为:紫外光光照强度、初始过氧化氢投加量、反应停留时间;运用交互分析方法得到每2个因素交互作用影响程度,得出双氧水初始投加量与反应停留时间交互作用为最大交互影响因子。     

The effect of tallow-based detergents on anaerobic digestion

Eight anionic detergents from three general classes (alcohol sulfates,a-sulfo fatty acid esters and alkylbenzenesulfonates were tested for biodegradability under anaerobic conditions of sludge digestion. The alcohol sulfates were found to be readily and completely degraded. Thea-sulfo fatty acid esters did not degrade but had no adverse effect on bacteriological digestion while the alkylbenzenesulfonates used for control purposes did not degrade and disrupted the normal digestion process. Preliminary lysimeter studies showed that sodium isopropyla-sulfostearate is completely degraded, linear alkylbenzenesulfonate 83%, and ABS 35%. Presented at the AOCS meeting, Chicago, 1964. E. Utiliz. Res. Devel. Div., ARS, USDA.     

A study of the biodegradation of anionic synthetic detergents a new laboratory test

The biodegradation of anionic synthetic detergents is studied by means of a new laboratory test. The bacterial source used in this test is activated sludge from the Sewage Works at Amsterdam. Important differences in biological “softness” were found between various detergents with this test, which gives results similar to those found in pilot plant experiments.     

The course of biodegradation of anionic detergents by analyses for carbon,methylene blue active substance and sulfate ion

Tallow alcohol sulfates, ether alcohol sulfates and esters of α-sulfo tallow fatty acids were degraded aerobically by sewage microorganisms in a system in which detergent was the sole source of C. Biodegradation was followed by loss of C and methylene blue active substance (MBAS) and formation of SO ₄ ⁻⁻ . Tallow alcohol sulfates were rapidly and completely degraded; ether alcohol sulfates not quite as readily. Reduction in MBAS was rapid for the α-sulfo esters but loss of C and SO ₄ ⁻⁻ formation was incomplete, possibly because of the intermediate formation of a resistant sulfosuccinate. Sodiump-(1-methylundecyl) benzenesulfonate (LAS) was the reference standard. Presented at the AOCS Meeting, San Francisco, April 1969.     

Micelle formation in mixtures of nonionic and anionic detergents

This paper describes the effect of a homologous series of polyoxyethylene n-dodecanols on the critical micelle concentration (CMC) of sodium n-dodecyl alcohol sulfate as a function of composition of the mixtures and temperature. The CMC of the nonionic component of the mixed micelles is about one-hundredth of that of the anionic. Only a gradual increase in the CMC values of the mixed micelles above the values of the nonionic components was observed in the composition range of 0–90 mole % anionic detergent. This is followed by an abrupt transition to the high CMC values of the anionic component. The gradual increase of the CMC values in the range below 90 mole % anionic detergent of n-dodecanol+ 4 EO exceeds that of the higher homologs containing 7, 23 and 30 ethylene oxide units. It is postulated that the degree of ionic repulsion of the ionic component in mixed micelles is markedly decreased as the proportion of nonionic component reaches a threshold range of 10 mole %. This effect is more pronounced with large ethylene oxide coils operating at the periphery of the micelle core than with short ethylene oxide coils. Thermodynamic data have been included.     

Analysis of traces of anionic detergents in oils and fats

A method to analyze oils and fats for anionic detergents, mainly sodium lauryl sulphate (NaLS), has been developed. After extracting the detergent from the oil, a chloroform-soluble complex with methylene blue is formed, and the concentration of this complex is determined spectrophotometrically. The method was found suitable for oils and fats containing 0.05 to 5.0 mg NaLS per kg. The analysis can only be used to assess fully refined oils and fats because partly refined and commercially available products may contain minor components and emulsifiers also solubilizing methylene blue into chloroform.     

Interaction of synthetic polyampholytes with anionic and cationic detergents in aqueous solution

Summary The interaction of amphoteric macromolecules with ionic surfactants is accompanied by a strong decrease of the dimensions of the polyelectrolyte chains, but the complex particles are retained from precipitation by the presence of the hydrophylic components of the polyampholyte. The behaviour of the complex polyampholyte-detergent depends both on the nature of amphoteric copolymers and on the ionic detergents.     

Thermogravimetric determination of water in household liquid detergents

Thermogravimetric analysis has been applied successfully in determining the amount of water constituent in household liquid detergents. Results were comparable to those obtained from the standard methods of testing. The simple, rapid technique is potentially useful and can be considered as a supplementary tool to the conventional methods of analysis.     

The detergents and water quality standards

The residual surfactants in watercourses as a result of detergent use have made the public more aware of water pollution. This awareness has accelerated the Federal water pollution control program especially in the research area. Research at two new Public Health Service laboratories will define the effects of specific materials on specific water uses. All of the detergents in common use will be studied. These research findings coupled with the comprehensive drainage basin studies will permit management decisions on the limiting concn of materials in water. p]Another phase of research which concerns the PHS is the development of new methods to remove more materials from waste waters. The active participation and cooperation of industry is needed in this endeavor in order to arrive at water quality standards which are readily attainable. The detergents could well be an indicator of efficiency in removing organic materials from waste waters.     

Determination of water content of granulated detergents

A quick analytical procedure was described for the determination of water content of granulated detergents. A constant weight loss of sample was obtained within 5 min by microwave drying. The weight loss agrees with the water content by the modified distillation method. The coefficient of variation was 0.7%.     

Alkaline methylene blue method for determination of anionic surfactants and for amine oxides in detergents

The concn of anionic surfactants in alkaline media has been determined by modification of the methylene blue titration. The method is based on the oxidation of methylene blue chloride to dimethylthionoline, a red dye, in the presence of chloroform and sodium hydroxide. This method in conjunction with the acid methylene blue titration, also may be used to determine the amt of amine oxides in formulated products. For concns of less than 100 ppm a spectrophotometric method was used.     

Reduction of phosphate builder in tallow-based detergent formulations

Laboratory washing tests using two different kinds of standard soiled cotton were made to compare built solutions of hydrogenated tallow alcohol sulfate (HTAS), sodium methylα-sulfotallowate (NaMeαST) and linear alkylbenzenesulfonate (LAS) in hard water of 300 ppm at 60 C. Most of the experiments were at 0.25% total concentration (0.05% active ingredient plus 0.20% builder). Phosphate reduction, without loss in detergency, can be accomplished in some cases but not in others, depending both upon the detergent and the test cloth. Both cloths have shown with HTAS as the active ingredient, that reduction in phosphate builder is possible without loss in detergency. The effect of other changes in formulation has been determined. Presented at the AOCS Meeting, Minneapolis, October 1969. Deceased. ARS, USDA.     

水中阴离子表面活性剂测定方法概述

简要介绍了表面活性剂的性质,阴离子表面活性剂的种类及其对水体环境的危害;重点对水中阴离子表面活性剂的测定方法即分光光度法、两相滴定法、高效液相色谱法、薄层层析法及离子选择性电极分析法等进行了综述;提出了水中阴离子表面活性剂测定方法向信息化、实时快速在线监测智能化和检测仪器向微型化的方向发展。     

环境中阴离子表面活性剂检测方法研究进展

概述了阴离子表面活性剂给水环境带来的危害,深入分析了目前阴离子表面活性剂的主要测定方法以及各优缺点,并对今后检测方法的改进方向进行了介绍,指出联用技术将成为未来水环境中阴离子表面活性剂检测的主要技术。     

Liquid detergents from cationic,anionic and nonionic surfactants. adsorption,detergency and antistatic properties

The adsorption of a mixture of cationic (c) and anionic (a) surfactants on cellulose fibers is highly dependent on the molar ratio a/c with a maximum at a/c = 0.9. When a/c is > 1.1 the adsorption is negligible. The presence of nonionic surfactants in the solution impairs the adsorption of the ionic species; this effect is stronger for nonionic surfactants with long alkyl and polyglycol ether chains. The detergency—measured on WFK cotton cloth—is highest when a/c > 1 and decreases sharply when a/c goes below 0.8. The antistatic effect for a formulated liquid detergent based on these principles was compared to one commercial liquid detergent with softening and antistatic properties and one commercial detergent powder, and the test detergent was shown to be a better antistatic agent on polyester, polyacrylonitrile and polyamide. The detergency was about the same for the two liquid detergents.     

分光光度法测定水中微量阴离子表面活性剂

在用HCl溶液调节pH=12.0的NaOH溶液中,5-甲基-2-[3-(4-苯基-2-噻唑基)三氮烯基]苯磺酸(MPTTBSA)与氯化十六烷基吡啶(CPC)形成离子缔合物MPTTBSA-CPC。在该溶液中加入阴离子表面活性剂时,能定量置换出离子缔合物中的MPTTBSA,使缔合物在最大吸收波长556 nm处的吸光度下降,阴离子表面活性剂的浓度与溶液的褪色程度呈良好线性关系,从而建立了阴离子表面活性剂光度测定法。实验结果表明,十二烷基磺酸钠(SLS)和十二烷基苯磺酸钠(SDBS)的表观摩尔吸光系数分别为1.24×104 L·mol-1·cm-1和1.07×104 L·mol-1·cm-1,在0～2.5×10-5 mol·L-1范围内服从比尔定律。该方法应用于生活污水中微量阴离子表面活性剂(以SLS计)的测定,结果与亚甲基蓝法测定结果基本一致。