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1.
The objective of this work was to apply a microemulsion-based formulation for the removal of motor oil in laundry detergency at low salinity. To produce the desired phase behavior, three surfactants were used: alkyl diphenyl oxide disulfonate (ADPODS), sodium dioctyl sulfosuccinate (AOT) and sorbitan monooleate (Span 80). The mixed surfactant system of 1.5% ADPODS, 5% AOT and 5% Span 80 (13 parts ADPODS, 43.5 parts AOT, and 43.5 parts Span 80 of the total actives) was found to form a middle phase microemulsion (Type III) at a relatively low salinity of 2.83% NaCl. When this formulation was diluted, detergency performance increased with increasing total surfactant concentration and leveled off above about 0.1% total actives on the three types of fabrics studied (pure cotton, 65/35 polyester/cotton blend, and pure polyester). Detergency was found to improve with increasing hydrophilicity of the fabric with cotton being cleanest after washing and polyester the most difficult to clean. To achieve a specified oil removal, less rinse water can be used if a higher number of lower-volume rinses are employed. An interesting characteristic of microemulsion-based formulations is that a substantial fraction of oil removal occurs during the rinse cycle. In this work, this removal is shown to be due to the low oil/water interfacial tension during initial rinsing and is therefore strongly correlated to residual surfactant concentration in the rinse steps. As a result, the number of rinses and the volume of water per rinse can profoundly affect detergency in these systems.
Sumaeth ChavadejEmail:
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2.
In spite of the increasing interest in cold temperature detergency of vegetable oils and fats, very limited research has been published on this topic. Extended surfactants have recently been shown to produce very promising detergency with vegetable oils at ambient temperature. However, the excessive salinity requirement (4–14 %) for these surfactants has limited their use in practical applications. In this work, we investigated the mixture of a linear C10–18PO–2EO–NaSO4 extended surfactant and a hydrophobic twin‐tailed sodium dioctyl sulfosuccinate surfactant for cold temperature detergency of vegetable oils and semi‐solid fats. Four vegetable oils of varying melting points (from ?10 to 28 °C) were studied, these were canola, jojoba, coconut and palm kernel oils. Anionic surfactant mixtures showed synergism in detergency performance compared to single surfactant systems. At temperatures above the melting point, greater than 90 % detergency was achieved at 0.5 % NaCl. While detergency performance decreased at temperatures below the melting point, it was still superior to that of a commercial detergent (up to 80 vs. 40 %). Further, results show that the experimental microemulsion phase behaviors correlated very well with predictions from the hydrophilic–lipophilic deviation concept.  相似文献   

3.
Cold water detergency of triacylglycerol semisolid soils is much more challenging than liquid vegetable oils due to poorer interaction between surfactants and semisolid soil. This research seeks to improve the removal efficiency of semisolid soils below their melting points using surfactant-based formulations containing different alcohol additives. To this end, cold water detergency of solid coconut oil and solid palm kernel oil was investigated in various surfactant/alcohol systems, including single anionic extended surfactants, single nonionic alcohol ethoxylate surfactants, and a mixture of anionic surfactants. A series of alcohols (2-butanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, and 1-decanol) were added to the surfactant formulations to investigate cold water detergency improvement. While cold water detergency using surfactants alone was poor, it was considerably improved when optimum salinity (S*) and 1-heptanol, 1-octanol, or 1-nonanol were introduced to the studied surfactant formulations. The maximum detergency of solid coconut oil exceeded 90% removal in the 0.1 w/v% C14-15-8PO-SO4Na/0.2 w/v% 1-octanol/4 w/v% NaCl system (a final optimized surfactant system) at a washing temperature of 10°C versus 22.9 ± 2.2% in the surfactant alone (not at optimum salinity and no additive). Further analysis showed that improved cold water detergency using surfactant/intermediate-chain alcohols/NaCl could be correlated with high wettability (low contact angle) as well as favorable surfactant system-soil interaction as observed by lower interfacial tension values. In contrast, the improved cold water detergency was observed to be independent of dispersion stability. This work thus demonstrates that surfactant system design, including additives, can improve cold water detergency of semisolid soils and should be further explored in future research.  相似文献   

4.
In this study, the impact of water hardness and builder on the phase diagrams of motor oil microemulsions and the detergency of oil removal from a polyester/cotton blend was investigated. Water hardness and builder were found to have insignificant effects on the microemulsion phase diagram with motor oil. A mixed surfactant system of two parts C14–15(PO)3SO4Na, and 98 parts C12–14H25–29O(EO)5H of the total actives at 4% salinity was used to study the effect of water hardness and builders sodium tripolyphosphate (STPP) or ethylenediaminetetraacetic acid (EDTA) on detergency at 30 °C at a total active concentration of 0.3%. This formulation is in the Winsor Type III microemulsion regime. The microemulsion-based formulation resulted in better detergency than a leading commercial liquid laundry detergent at all concentrations up to 0.5% actives. The microemulsion-based formulation showed a plateau in detergency at >80% oil removal above 0.1% actives. The total oil removal decreased with increasing water hardness while the interfacial tension increased. When hard water was used in laundering, the total oil removal improved with increasing concentrations of STPP or EDTA up to stoichiometric levels, with STPP being slightly more effective than EDTA on a molar basis. Even high builder concentration could not improve hard water detergency to that of soft water. A significant fraction of oil removal occurred in the rinse steps vs. the wash step. Increasing water hardness reduced this fractional oil removal in the rinse steps, but it was still over half of total oil removal at 1,000 ppm water hardness.
Sumaeth ChavadejEmail: Email:
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5.
利用植物油脂合成香料   总被引:5,自引:0,他引:5  
利用可再生的天然油脂替代有限的石油资源制备高附加值的精细化学品,已引起世界各国的高度重视。本文介绍了从植物油脂出发合成大环麝香、内酯、脂肪酸酯及脂肪醛等香料,旨在为天然油脂的深加工提供依据。  相似文献   

6.
Our prior work found that detergency of coconut oil was relatively poor using C14-15-8PO-SO4Na alone but showed promising improvement with the presence of linear intermediate-chain alcohols (C7–C9 alcohols) in the surfactant formulation. The maximum detergency exceeded 90% removal using 0.1 w/v% C14-15-8PO-SO4Na/0.2 w/v% 1-octanol/4 w/v% NaCl (final optimized surfactant system) at 10 °C. The current work thus seeks to further investigate surfactant formulations capable of providing improved detergency performance. Different 50% linear anionic extended surfactant structures (LC14-15-8PO-SO4Na, LC14-15-8PO-3EO-SO4Na, and LC14-15-8PO-7EO-SO4Na) were compared with the branched C14-15-8PO-SO4Na previously studied. Detergency of coconut oil using C14-15-8PO-SO4Na at 8 w/v% NaCl (S*) still performed more effectively than these new surfactant systems. The addition of octanol as a detergency additive was further studied, and it showed that S* reduced from 8 w/v% NaCl to 4 w/v% NaCl for 1-octanol and to 2 w/v% NaCl for 2-octanol and 2-ethyl-hexanol in the C14-15-8PO-SO4Na surfactant formulation. Coconut oil removal significantly improved detergency from roughly 49% for no alcohol with 8 w/v% NaCl, to 83% for 2-ethyl-hexanol with 2 w/v% NaCl, to 95% for 1-octanol with 4 w/v% NaCl, and to 98% for 2-octanol with 2 w/v% NaCl. Further studies on octanol concentration showed that decreasing 1-octanol from 1.2% (90 mM) to 0.2% (15.3 mM) and 2-octanol from 1.2% (90 mM) to 0.5% (38.5 mM) still maintained detergency over 90% removal. In this work, cold-water detergency was found to correlate with low interfacial tension above the melting point, improved wetting of the semisolid soil, and oil solubilization in surfactant micelles.  相似文献   

7.
The development of environmentally benign products has been the subject of growing interest in the field of surfactant chemistry. Acyl amino acid surfactants bearing lysine, serine, threonine, and methionine residues were synthesized using natural oils extracted from coconut, palm kernel, and soybean as acyl donors. The chemical structures were confirmed by high-performance liquid chromatography (HPLC/MS) and infrared (IR) spectra. Their surface activities, ion-specific effects, detergency, and foam properties were studied systematically. The critical micelle concentration (CMC) values depend significantly on amino acid and oil types and follow the orders: (i) Lys > Thr ≈ Ser > Met and (ii) Coconut ≈ Palm kernel > Soybean oil. Interestingly, the ion-specific effects showing that the γCMC value decreases with increasing counterion size and hydrophobicity were observed, and the results were consistent with the famous Hofmeister series. The detergency ability of acyl amino acid surfactants is better than multiple traditional surfactants in distilled water. Although the detergency ability of our products for oil-soiled swatches decreased significantly in hard water, this problem was solved by the C-Lys-Na/AES mixed system showing excellent synergistic effects. Excellent foamability and foam stability were achieved for acyl threonine and serine bearing hydroxyl groups on their headgroups, suggesting that the packing of these surfactants at the air–water interface was assisted by hydrogen bonding.  相似文献   

8.
Vegetable oils have kairomonal attractant properties to grasshoppers primarily due to the presence of linoleic and linolenic fatty acids. These fatty acids are dietary essentials for grasshoppers and, once volatilized, can be detected by the insects’ olfactory receptors. A laboratory bioassay method has been developed to identify vegetable oils that have fatty acid profiles similar to grasshoppers and that induce grasshopper attraction and feeding. Such oils could be useful kairomonal adjuvants and/or carriers for acridicide formulations. Three sets of laboratory bioassays demonstrated that the addition of a standard aliquot of different vegetable oils resulted in varying degrees of grasshopper feeding on otherwise neutral substrates. Addition of olive oil stimulated the greatest feeding in all three sets of assays, regardless of the age of the tested insects. Furthermore, addition of canola or flax oils markedly enhanced grasshopper feeding. These three oils—i.e., olive, canola, and flax oil—proved to be the best performing grasshopper stimulants. A second group of oils included rapeseed-flax mix and rapeseed oils; however, their performance was not as consistent as oils in the first group—especially with regard to nymphal feeding. A third group of oils consisted of soybean, corn, peanut, and sunflower oil. Theoretical expectations regarding these oils varied wildly, suggesting that the results of a single bioassay should be cautiously interpreted as being negative.  相似文献   

9.
In this study, differentiation of vegetable oils and determination of their major fatty acid (FA) composition were performed using Raman spectral barcoding approach. Samples from seven different sources (sunflower, corn, olive, canola, mustard, soybean and palm) were analyzed using Raman spectroscopy. Second derivative of the spectral data was utilized to generate unique barcodes of oils. Chemometric analyses, namely, principal component analysis (PCA) and partial least square (PLS) methods were used for data analysis. PCA was applied for classification of the samples according to the differences in their levels arising from their barcode data. A successful differentiation based on second derivative barcodes of Raman spectra (2D‐BRS) of vegetable oils was obtained. In addition, PLS method was applied on 2D‐BRS in order to determine the major FA composition of these samples. Coefficient of determination values for palmitic, stearic, oleic, linoleic, α‐linolenic, cis‐11 eicosenoic, erucic and nervonic acids were in the range of 0.970–0.989. Limit of detection and limit of quantification values were found to be satisfactory (0.09–8.09 and 0.30–26.95 % in oil) for these fatty acids . Advantages of both chemometric analysis and spectral barcoding approach have been utilized in the present study. Taking the second derivative of the Raman spectra has minimized background variability and sensitivity to intensity fluctuations. Spectral conversion to the barcodes has further increased the quality of information obtained from Raman spectra and also made it possible to improve the visualization of the data. Converting Raman spectra of oils into barcodes enables simpler presentation of the valuable information, and still allows further analysis such as classification of vegetable oils and prediction of their major fatty acids with high accuracy.  相似文献   

10.
Environmentally friendly vegetable oils and their derivatives represent alternatives to mineral-based lubricants. Vegetable oils have high biodegradability and low production costs. Their poor thermo-oxidative stability and poor low temperature properties are disadvantages in their use as lubricant basestocks. In our study we used corn oil and diester mixtures, which become lubricants when additives are introduced. These mixtures of corn oil and di-2-ethylhexyl-adipate (DOA) and di-2-ethylhexyl-sebacate (DOS) offer a wide range of kinematic viscosities, pour points lower than −39 °C and flash points over 218 °C. The diameters of wear scars measured under four-ball testing (40 daN) are less than 0.90 mm and the copper strip corrosion test result is 1a. The differential scanning calorimetry study and thermogravimetric study under nitrogen atmosphere and in synthetic air are reported. From these studies a higher thermal stability was observed for corn oil than for diester oils. The thermo-oxidative instability occurred at temperatures higher than 350 °C. The low production cost of corn oil and its mixtures with diesters makes them an attractive alternative to mineral oil lubricants.  相似文献   

11.
为北方城市污水处理的CAST工艺在冬季进水温度低和有机负荷低的条件下进行启动调试及活性污泥培养驯化提供经验,促进该工艺在寒冷地区的推广应用.研究结果表明,在冬季进水温度低和有机负荷低的条件下,采用接种法培养驯化活性污泥20天就能完成污泥培养驯化,满足污水处理要求,出水达到设计标准.北方城市污水处理的CAST工艺在冬季低水温、低有机负荷低的条件下应采用接种法培养活性污泥.  相似文献   

12.
低温化学镀镍液中次磷酸钠还原效率的研究   总被引:1,自引:0,他引:1  
对化学镀镍的反应机理进行分析,提出次磷酸酸钠还原效率的概念,推导出次磷酸钠还原效率的计算公式,通过实验测定低温化学镀镍工艺中次磷酸钠的还原效率,并讨论了次磷酸钠、络合剂以及加速剂对次磷酸钠还原效率的影响。  相似文献   

13.
The search for alternative fuels has been gaining attention in recent decades. The replacement of fossil fuels is driven by environmental, economic, and social factors, since the whole of society is dependent on their usage; and in this context, one alternative that has been highlighted is the use of biodiesel. Biodiesel represents a renewable, biodegradable, non‐inflammable, and low toxicity alternative to diesel. In this study, the Hansen solubility parameters (HSPs) and the interaction radii (R0) were determined for the following materials: used frying oil, coconut oil, palm oil, biodiesel from used frying oil, diesel, and biodiesel–diesel blends (B10 and B20), using 45 solvents and solvent mixtures. The values found for the solubility parameters of the used frying oil and coconut oil were very close to those found for the biodiesel; however, the biofuel showed higher solubility in polar solvents. The values of solubility parameters of diesel, B10, and B20 were similar, increasing values according to the amount (by volume) of biodiesel added to diesel fuel.  相似文献   

14.
改性活性炭低温脱除COS的实验研究   总被引:8,自引:0,他引:8  
张金昌 《辽宁化工》1998,27(2):102-104
模拟3018脱硫剂常温脱出H2S的一些基本条件,探讨了3018脱硫剂脱出COS的情况。结果表明在常温条件下脱COS的反应速率很慢,在温度为80℃左右时显示了较好的脱出COS的性能,为今后优化组合工艺的开发,实现3018脱硫剂同时脱出H2S和COS提供了理论基础。  相似文献   

15.
Critical micelle concentration (CMC) is a fundamental physical parameter of surfactant aggregation in solution. The CMC is determined by different methods, tensiometry, conductometry, microcalorimetry, fluorimetry, and so on. However, it is known that though CMC is reported as a single value, in reality, micelle formation occurs over a narrow range of concentration for different experimental procedures produce different results. We shall discuss about a unique procedure of measuring correct CMC applicable to all potential methods used in practice. This is essential for the evaluation of thermodynamic properties of the micelle forming process in pure and mixed states in terms of solution theories. As we in this short documentary want to deal with various aspects of Milton Rosen's research—wherein we have also worked—a few other facets of surfactant chemistry research, besides the micelle formation, are also briefly discussed. In mixed surfactant systems, synergistic effects in various surfactant properties like detergency, foaming, solubilization, and so on are found whereas in some others non-synergistic effects are observed. Dehydration of micelles with an increase in temperature or by the addition of hydrophilic substances may cause clouding to the system. Soluble amphiphilic systems produce Gibbs monolayer at the air/water interface; insoluble amphiphiles form Langmuir monolayers. A documentary of the above aspects will be herein presented and discussed. We mention that this article is neither an original research article nor a review article. This is a mixture of the two: a documentary of both original research and some review of our works presented in memory of Prof. Milton Rosen.  相似文献   

16.
储章生 《江苏陶瓷》1998,31(2):10-11
简要地叙述了国家八五攻关项目“85-705”中“低温低介电常数陶瓷材料”这一课题的研制过程及关键工艺技术问题  相似文献   

17.
基于Monod方程和工艺特点,本文对SBR基质降解动力学进行了理论推导,并通过实验确定和验证了在低水温下的降解模型t=((S0-Se)/(9.048×10-4Xv(Se-18.02))),这对测算最佳反应时间和指导实际运行具有重大意义。  相似文献   

18.
低温相变储能材料及其应用   总被引:1,自引:0,他引:1  
人类对能源的需求日益增加,但是能量利用率不高的问题难以解决。相变储能技术在能源的合理利用、各行业的技术升级与人类生活品质提升的过程中都发挥了重要作用。对相变材料进行了分类并归纳了不同类别相变材料的机理、性能以及其优劣势。根据低温相变储能材料的应用实例归纳了相变储能材料的四大功能:能量调配,温度控制,能量吸收与记忆储存。对相变材料的研究及其发展方向提出相关建议。  相似文献   

19.
提高低温感装药的能量及弹道性能的方法   总被引:1,自引:0,他引:1  
王煊军  王泽山 《火炸药》1996,19(3):7-10
阐述了一种提高低温感装药能量及弹道性能的原理及方法,给出了制备工艺流程和工艺条件;并讨论了该方法对膛压和初速的影响及其应用的可能途径;通过30mm火炮射击试验,证实它具有增能和低温感双重效果,是一种有发展前途和实用价值的发射药装药技术。  相似文献   

20.
低浓度污水厌氧生物处理国内外发展现状   总被引:1,自引:0,他引:1  
回顾了污水厌氧生物处理工艺的发展历程,着重介绍了升流式厌氧污泥床(UASB)、两级系统、厌氧膨胀颗粒污泥床(EGSB)和厌氧折流板反应器(ABR)等厌氧生物处理工艺处理低浓度污水的国内外发展现状.  相似文献   

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