Development of an Environmentally Acceptable Detergent Formulation for Fatty Soils Based on the Lipase from the Indigenous Extremophile Pseudomonas aeruginosa Strain

A lipase derived from an indigenous extremophile Pseudomonas aeruginosa strain isolated from rancid metalworking fluid was evaluated as a detergent additive. Applicability of the obtained enzyme as an additive in detergent formulations was confirmed by its implementation in the formulations of several new products differing in surfactant type and concentrations, demonstrating satisfactory performance in terms of degreasing efficiency and composition of the washing wastewater. The degreasing efficiency of different enzyme‐containing detergent formulations was studied on cotton fabric samples stained with triolein and compared to that of formulations containing only surfactant. The highest efficiency of the fatty soil removal in formulations with a low content of surfactants (0.4 %) was noted in the enzyme formulation containing Lutensol^® XP‐80 (degreasing efficiency >80 %) and Triton^® X‐100 (degreasing efficiency >60 %). An attempt was then made to optimize the composition of the enzyme formulation on the basis of one or both of these surfactants using statistically planned experiments and response surface methodology (RSM). Taking into consideration the environmental aspects and the shown detergency, it appeared that rather high degreasing effects were achieved in formulations based on a low quantities of Lutensol^® XP‐80 (0.4 %) at all pH values. However, pH seemed to have a notable effect since the degreasing efficiency significantly increased with increasing pH and the amount of the enzyme. Formulations having a moderate alkaline pH profile and higher amount of enzyme exhibited a high cleaning performance of fatty soil even at a low concentration of the surfactant.     

Flux recovery of tubular ceramic membranes fouled with whey proteins

Membrane process efficiency is governed by the formation of fouling deposits during processing of dairy fluids. Because of fouling with whey proteins, permeate flux can drastically decline during filtration process. This paper describes the flux recovery procedure for ceramic tubular membranes (50 and 200 nm pore sizes) fouled with whey proteins. The results comprehend the effect of rinsing and cleaning agent choice and concentration, on the cleaning efficiency. As chemical cleaning agents, the caustic solution and the commercial detergents P3-ultrasil 67 and P3-ultrasil 69 were selected. The observations are that rinsing with deionised water contributes to a flux recovery to a certain degree. For the 50 nm membrane, the choice of the 1.0% (w/w) caustic solution, as cleaning agent, gives the best flux recovery. For the 200 nm, total flux recovery was not observed regardless of the cleaning agent choice and concentration. Cleaning with chosen commercial detergent appeared to be less efficient than cleaning with caustic solution for the chosen ceramic membranes. Also, a mathematical model, proposed in this study, has shown high agreement with experimentally obtained data.     

Kinetic studies of detergency. III. Dependence of the dupré mechanism on surface tension

The kinetics of the removal of thin films of pure radioactive tristearin from a stainless steel surface by detergent solutions in a circulation cleaning system were used to study the effect of the surface tension of the detergent solution on the Dupré mechanism and the flow mechanism. Lowering the surface tension reduced the effectiveness of the Dupré mechanism for both species 1 soil and species 2 soil, as expected. Lowering the surface tension increased the efficiency of the flow mechanism for both species of soil, but, at the present time, it is not known how much of the increase can be ascribed to the lowered surface tension, and how much is due to the increased concn of the surfactant that was used to lower surface tension.     

金属表面渣油清洗剂的研制

采用失重法筛选出几种对金属表面渣油具有良好清洗效果的表面活性荆。将表面活性剂和清洗助剂等进行复配,获得了高除垢率清洗剂配方。同时,测定了该清洗剂在4种金属表面的除垢率,并对该清洗剂的脱脂温度、脱脂时间等相关性能进行了测试。实验结果表明：常温下,使用该清洗剂经过2．5h清洗,在4种金属表面的清洗率均可达到较理想效果。该清洗剂具有非常优良的清洗能力,环境污染小,安全性高,可以满足工业需求。     

An optimized hard surface cleaning test

Preliminary investigation of several test procedures resulted in the selection of the Liss-Hilton reflectance method. A white vinyl tile substrate was selected and the test method optimized at cleaning efficiencies of approximately 30% for water and 80% for selected detergent compositions. Within-series and between-series variations, in general, met a required 2% maximum. Between-laboratories data were slightly more variable. Utilizing the corresponding confidence limit factor, as few as three test panels per detergent may be used to compare detergent cleaning efficiencies.     

低温高效低泡水基冷轧钢板脱脂剂的研制

为解决冬季常温冷轧钢板脱脂中,由于水温低,造成水基脱脂剂洗净率低,易发泡的问题,在3℃下研究了两种嵌段醇醚非离子表面活性剂复配体系的去污性能及其清洗液的泡沫行为,以及聚三元羧酸酯(H5768)、硼酸三乙醇胺酯的复配体系对钢材的缓蚀作用。结果表明,开发了在低温下低泡、高效、防锈及环保的水基冷轧钢板脱脂剂最佳配方为:10%~15%氢氧化钠,0.8%~2.0%无水偏硅酸钠,5%~8%葡萄糖酸钠,2%~4%H5768,1%~3%硼酸三乙醇胺酯,1%~3%PAA,5%~8%WP173,2%~4%RPE3110,53.0%~73.2%水。在3℃及以上温度下脱脂剂无泡,且能有效抑制清洗中由于油污皂化引起的泡沫,3%脱脂剂,清洗2 min,对冷轧钢板洗净率可达99%以上,对铸铁、碳钢及合金钢有很好的防锈性能,各项性能符合JB/T4323.1-1999标准。     

铝材表面脱脂除油清洗剂的研究

开发出一种新的铝材脱脂除油清洗剂。该铝材脱脂除油清洗剂既保证了脱脂效果,又减缓了清洗液对铝材质设备的腐蚀。在50℃条件下脱脂除油率可达到98％以上,而该清洗液对铝材的腐蚀率小于1g／（m2·h）。     

快速滚光除油剂的研究及应用

滚光除油工艺在电镀业中应用广泛。为消除传统工艺中三氯乙烯对环境的有害影响,研制出一种ＢＨ－７Ａ快速滚光除油剂。根据ＪＢ４３２２－８６水基金属清洗剂试验方法对其各项进行了测试,并分析了其成分和除油机理。结果表明：该除油剂各项性能均达到了ＪＢ－４３２３－８６水基金属清洗剂质量指标。其组成主要为多种表面活性剂、清洗促进剂和擦光剂,清洗效果好,完全可取代传统的三氯乙烯加碱油的快速滚光除油工艺。     

Using the 3-point bending method to study failure initiation in epoxide-aluminum joints

The increasing use of adhesives in industry has boosted the search for tests which allow the adherence level to be defined. These tests, depending on the type of load, examine different stresses, failure modes and mixed modes. Furthermore, these tests can be focused either on initiation or propagation of adhesive failure. The subject of this study is the initiation of adhesive failure. The initiation of failure can be determined with the 3-point bending test. Trials of 3-point bending tests were conducted on an aluminum 2024 substrate, with two different thicknesses, in order to understand the impact of the adherend thickness. The aluminum substrate received different types of surface pre-treatment: acetone cleaning, hydrochloric acid etching or aminopropyltriethoxysilane coating. Two adhesives were used: the first one was a mixture of epoxy pre-polymer DGEBA and DETA amine, whereas the second was a commercially formulated adhesive, ELECOLIT 6604. The initiation of adhesive failure was obtained by 3-point bending test and verified with SEM analysis. The failure loads measured enabled the effect of surface treatment on adhesive failure to be revealed: the results indicate that the surface treatment with silane is the most efficient in comparison to hydrochloric acid etching and of course to the simple acetone degreasing. It was assumed that the scatter of the results obtained for each series is due to the variation of the “intrinsic” adherence between the adhesive and the substrate. Furthermore, it was noted that the failure loads for different substrate thicknesses cannot be compared due to the effect of the thickness: it was therefore not possible to simply compare results obtained for different thicknesses of the same substrate for a given substrate-adhesive system. The energy approach proposed in this study makes it possible. The energy requested to initiate the adhesive failure for a given system can then be known, whatever the initial geometry of the 3-point bending test is. However, it was also shown that the thickness of the substrate must be correctly chosen. A thick substrate increases the dispersion and a thin substrate may induce local unwelcome plastic strain. In conclusion, this study allows to define an energy criteria for adhesives failure initiation.     

A realistic soil cloth and test procedure for detergent evaluation

The preparation of a uniformly soiled cloth for detergency studies is described. The soil, chosen for its realistic nature, consists of a colored clay as the particulate portion and triolein as the fatty or oily portion. The particulate portion of the soil is applied by tumbling the fabric in a horizontal axis washing machine containing a suspension of clay. The fatty portion is then applied by allowing the fabric to adsorb a known quantity of solvent-dissolved triolein with subsequent evaporation of the solvent. An evaluation test procedure for measuring the relative efficiencies of proprietary detergents is also described. Using this procedure, soil removal, soil redeposition and optical brightener effectiveness of a detergent are determined simultaneously. Detergents can thus be given a numerical rating according to their over-all performance. This rating is calculated from the equation: Overall Performance=Soil Removal−Soil Redeposition + Optical Brightener. Typical detergent evaluation data obtained with this soil cloth and test procedure are given, along with a statistical treatment of the data.     

钢铁件除油除锈防锈一步法处理液的研究

以有机酸、磷酸、改性淀粉、锆脲络合物、复合表面活性剂等为原料制备出一种钢铁件除油除锈防锈一步法处理液。该处理液可用于钢铁制品涂装前表面处理、带钢冷轧过程及机械加工过程的工序间清洗和防锈处理,以代替传统的分步处理工艺。该处理工艺不仅简化了操作步骤,降低了操作成本,还解决了分步法中水洗废液的排放带来的环境污染问题。     

连续电镀无磷金属脱脂剂综合评价方法研究

电子接插件金属零件基材表面因模具冲压工艺过程中使用模具切削油而粘附大量油脂等污染物,因此,评估电镀前处理除油工序使用的脱脂剂的除油特性对电镀企业合理选用除油效果好、成本低、效率高及环保性能优良脱脂剂意义重大。为此,建立连续电镀脱脂剂的质量、效率、成本和环保特性的实验室综合评价试验方法,以供电镀生产过程选择经济适用环保的电解脱脂剂提供技术支撑,利用该评价方法对三种品牌的电解脱脂剂进行综合评价,结果显示,1#脱脂剂综合使用性能最优。     

Pretreatment with fine bubbles for effective zinc ion precipitation and removal from zinc electroplating wastewater

Heavy metals such as zinc are widely used in plating plants for the processing of material surfaces; therefore, an adequate wastewater treatment is required afterwards to comply with wastewater regulations. However, the presence of chemicals such as degreasing agents in the wastewater generated from the plating process inhibits the formation of hydroxides, thereby making treatment of wastewater and compliance with the stipulated regulations difficult. Herein, the effects of fine bubbles on oil cleaning and wastewater treatment were investigated for developing an alternative cleaning technology to degreasing agents. The concentration of fine bubbles significantly affected the oil cleaning. The fine bubbles demonstrated remarkable cleaning of highly viscous oil, which was difficult to remove using pure water. The high cleaning effect of fine bubbles on oil was achieved because of the hydrophobic interaction of the bubbles. Furthermore, a decrease in cleaning effect was observed for samples with uneven shapes, which was attributed to the difficulty in penetration of fine bubbles in materials with irregularities. Furthermore, fine bubble cleaning exhibited better efficiency for wastewater treatment than degreaser cleaning. Therefore, fine bubble cleaning is speculated to be an excellent cleaning technology with high oil cleaning effectiveness and improved wastewater treatability.     

水基油烟机重油垢清洗剂配方设计

探讨了水基油烟机重油垢清洗剂的去污机理,从重油垢清洗剂配方设计的3种主要手段出发,设计了正交实验,并采用测试清洗效率的分析手段对配方进行比较。通过正交实验结果,分析提高清洗效率的途径。通过摸索,得到清洗效率高于市售品牌的重油垢清洗剂,通过10min摆洗后的去污率为99．8％。该清洗剂具有液雾少、安全环保、对金属腐蚀性很小且去污效率高的优点。同时配方考虑了清洗剂与油垢表面的接触时间,使清洗剂发挥作用时间更长,同时尽可能地降低原料成本。     

飞机清洗剂清洗效率试验及影响因素分析

用超声振动辅助清洗剂清洗飞机,探讨了基材及其表面粗糙度、清洗时间对清洗效率的影响。结果表明,试件的材质和表面粗糙度对清洗效率值均有较大影响;清洗时间长能提高清洗效率,但是清洗时间过长,容易使试件造成腐蚀,导致试验结果不可信。     

钢铁件锌酸盐镀锌前处理方法

简单介绍了锌酸盐镀锌的特点及其添加剂的两种类型。对一般钢铁件进行化学除油、酸洗除锈后再次除油、预浸蚀,最后浸碱液,其间采用高压水清洗,对提高其锌酸盐镀锌的质量,起到了较好的效果。列举了酸洗除锈的一些典型配方,说明了其适用范围。     

微乳液除油剂的研究

针对常规除油不彻底,成本高,提出了用微乳液除油的方法,采用非离子表面活性剂和阴离子表面活性剂复配,添加助洗剂、络合剂等形成微乳液,研制了一种在常温下快速除去金属表面油污的高效微乳液除油剂。重点研究了脱脂温度以及脱脂时间对除油效果的影响,并测定了该微乳除油剂的其它性能和特点。试验结果表明,该微乳液除油剂具有节能、高效、低成本等特点。     

Removal of greases and lubricating oils from metal parts of machinery processes by subcritical water treatment

Toxic or persistent solvents have been widely used to remove greases and lubricants from various machine elements in the washing processes. In this study, an alternative degreasing method that employed subcritical state water was assessed. This environmentally benign solvent has significant potential for various degreasing applications. The operation time and temperature and flow rate of subcritical water had markedly positive impacts on the degreasing efficiency. However, the effect of pressure of subcritical water flow was minimal. The degreasing efficiency was also highly dependent on the physical characteristics and chemical composition of grease. The subcritical water treatment demonstrated a better degreasing efficiency than conventional degreasing methods. Only minor physical damage was observed on the metal parts after the subcritical water treatment. Conclusively, it was found that the subcritical water degreasing system can be used as an effective degreasing technology for machinery operations.     

Optimisation of Detergent Ingredients for Stain Removal Using Statistical Modelling

Artificially soiled test fabrics are widely used to study the cleaning performance of detergents formulations. In this study, artificial soiled cotton test fabrics were prepared in the laboratory using carbon black as a model soil. Design of experiments was used to optimise the concentration of detergent ingredients for stain removal. A multi‐factorial analysis of variance was used to model the effect of sodium dodecylbenzene sulfonate, nonylphenol ethoxylate, sodium silicate, sodium citrate and sodium carbonate as builders on soil removal. A colourimetric evaluation using the CIELAB system was used to measure soil removal. In general, performance increases with increasing concentration of surfactant, silicate and soda ash.     

A Surface Plasmon Resonance Optical Fibre Sensor for Testing Detergent Cleaning Efficiency

The objective of this paper is to report a feasibility study on the use of optical fibre and surface plasmon resonance (SPR) for determining detergent efficiency. The concept presented comprises a miniaturised dip‐sensor for enabling automated on‐line testing. In this way, the effect of formulation, concentration and temperature on the cleaning behavior of various surfactants and commercial cleaners is investigated. For this purpose, the decladded core of an optical fibre was sputtered with gold and afterwards coated with defined layers of stearic acid or animal fat to obtain a kind of model soil. The deposition of stearic acid was performed using a Langmuir–Blodgett through, and the sensor followed on‐line the deposition of the respective monolayers by UV/VIS spectroscopy, appearing as a distinct and constant shift in wavelength. Moreover, functional coatings were applied above the gold layer to achieve a variation of the hydrophilicity of the sensor surface. The SPR sensor proved to be easy to use, accurate and flexible. It offers a new solution that could replace the existing methods for detergency sensing and with a customised design it could be a useful industry tool since the small size of the dip sensor promises massive testing. The experiment also showed that functionalising the sensing zone could act as a way to mimic the potential substrates for cleaning.