Boosted Biodegradability and Tribological Properties of Mineral Base Oil by Methyl Diethanolamine Fatty Acid Esters

Methyl diethanolamine fatty acid esters, viz. methyl diethanolamine octanoate and methyl diethanolamine oleate,were prepared. Their impacts on the biodegradability and tribological properties of mineral base oil 400 SN were evaluated by a tester for fast evaluating the biodegradability of lubricants and by a four-ball tester, respectively. The results showed that methyl diethanolamine octanoate and methyl diethanolamine oleate both could markedly promote the biodegradation of the oil and improved its tribological properties. The improvement of biodegradability was attributed to the enhanced growth and quantity of microbes by methyl diethanolamine fatty acid esters. The worn surfaces were analyzed by a scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) and an X-ray photoelectron spectroscope(XPS). The results indicated that the enhancement of friction-reducing and anti-wear properties of the mineral oil was attributed to the formation of complicated boundary lubrication films composed of species such as Fe_2O_3, Fe_3O_4 and organic nitrogen-containing compounds with a structure of –C-N-or R-NH_2.

Epoxidation of Unsaturated Fatty Acid Methyl Esters in the Presence of SO_3H-functional Brφnsted Acidic Ionic Liquid as Catalyst

The epoxidation of unsaturated fatty acid methyl esters(FAMEs)by peroxyacetic acid generated in situ from hydrogen peroxide and acetic acid was studied in the presence of SO3H-functional Brnsted acidic ionic liquid (IL)[C3SO3HMIM][HSO4]as catalyst.The effects of hydrogen peroxide/ethylenic unsaturation ratio,acetic acid concentration,IL concentration,recycling of the IL catalyst,and temperature on the conversion to oxirane were studied.The kinetics and thermodynamics of unsaturated FAMEs epoxidation and the kinetics of oxirane cleavage of the epoxidized FAMEs by acetic acid were also studied.The conversion of ethylenic unsaturation group to oxirane, the reaction rate of the conversion to oxirane,and the rate of hydrolysis(oxirane cleavage)were higher by using the IL catalyst.

Effects of Yttrium Doping on the Performance of Ru-Based Catalysts for Hydrogenation of Fatty Acid Methyl Ester

The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was characterized by X-ray diffraction and field emission scanning electron microscopy. The results show that the average particle diameter of the bimetallic crystallites was less than 10 nm. The effects of the reaction temperature, the hydrogen pressure, the amount of catalyst and the proportion of yttrium in catalyst on the hydrogenation of ester were studied. The experimental results show that the introduction of yttrium not only changed the chemical and textural properties of ruthenium-based catalyst but also controlled the formation of Ru-Y alloy. The Ru-Y catalyst (Ru-2%Y/TiO2) exhibited high catalytic activity and good selectivity towards the higher alcohols. Under optimal reaction conditions of 240°C and 5 MPa hydrogen pressure, the conversion of palm oil esters was above 93.4% while the selectivity towards alcohol was above 99.0%.

Free fatty acids profiling in cold-pressed rapeseed oil pretreated by microwave

This study proposed a strategy based on simple chemical derivatization coupled with neutral loss scan tandem to electrospray ionization source of mass spectrometer (NLS-ESI-MS/MS) for rapid and sensitive detection of free fatty acids (FFAs) in coldpressed rapeseed oils without sample purification and enrichment. The method was applied to investigate contents of FFAs and their changes in cold-pressed rapeseed oil pretreated by microwave. Results showed that main FFAs in rapeseed oil control samples were myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). The highest content of C18:1 was 7163.69 nmol/g and C18:2 was 5221.18 nmol/g among 8 oil samples. FFAs generally increased after microwave pretreatment except C14:0 in oil sample of ‘Xinyou 17’ and ‘Suyou 6’. C18:1 and C18:2 significantly changed (P<0.05) after microwave pretreatment. With this established simple,practical and reliable analysis approach, changes of FFAs would be monitored to ensure safety and quality of edible oils. A powerful tool is provided for thermal degradation mechanism research of edible oils.

Enzymatic synthesis, antioxidant ability and oil-water distribution coefficient of troxerutin fatty acid esters

Troxerutin fatty acid esters were prepared using troxerutin and fatty acid vinyl esters as substrates in pyridine through enzymatic route. The structures of as-prepared compounds were identified by FT-TR, NMR, and ESI-HRMS. Using alkaline protease(≥30 mg/mL) as enzyme, maximum yields reached 58% at 3:1(vinyl hexanoate to troxerutin) in pyridine(water content ≤1%). The yields gradually declined as chain length of acyl donors rose. The antioxidation abilities of the as-obtained compounds were confirmed by both DPPH free radical scavenging and potassium ferricyanide reduction methods. The antioxidation ability of troxerutin fatty acid esters was found lower than that of troxerutin. However, the logP values of troxerutin fatty acid esters varied from 0.15 to 1.94, suggesting that troxerutin fatty acid esters had better lipophilicity than troxerutin(logP =-2.12) when compared to their oil-water distribution coefficients. Overall, these findings look promising as reference for further development of future troxerutin.

Ternary Liquid-Liquid Equilibrium for Systems of Fatty Acid Methyl Ester(Methyl Palmitate/Methyl Stearate)+Ethanol+Glycerol at Atmospheric Pressure

Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coefficient and selectivity were calculated, which indicates that glycerol can be separated from fatty acid ester by using ethanol as an extraction solvent. The consistency of the isothermal tie-line data were checked by the Othmer-Tobias equation. The correlation coefficients R2 are higher than 0.993,9 for all the fitted curves. The NRTL activity coefficient model was applied to the correlation of the measured tie-line data. The root mean square deviation(RMSD)values are less than 0.007 for all the systems, which shows a good predictive capability of this model for such systems.

Supercritical Synthesis of Ethyl Esters via Transesterification from Waste Cooking Oil Using a Co-Solvent

Biofuels became more promising alternative to the fossil fuels because of the depletion of fossil resources, renewability, environmental benefits, and energy security. Ethanolysis of waste cooking oil with hexane as co-solvent was carried out for the production of fatty acid ethyl ester (FAEE). This process reduced the severity of process parameters with high purity biodiesel yield. Process variables such as co-solvent ratio, ethanol to oil molar ratio, reaction temperature and reaction time were optimized. The maximum biodiesel yield of 88% was obtained at ethanol/oil molar ratio of 40:1, co-solvent (hexane) to oil ratio of 0.2% (v/v), reaction temperature of 300°C in 20 min of reaction time. Fatty acid ethyl ester (biodiesel) samples produced from this process were measured and evaluated using GC-MS analytical instrument. Thermo gravimetric analysis (TGA) was also performed to examine the thermal stability of waste cooking oil, ethyl esters and fuel blends. Fuel properties of ethyl esters were determined and compared with the ASTM standards for biodiesel, regular diesel and ethyl esters from different feedstock.

Determination of the Fatty Acid Profile of Breast Milk from Nursing Mothers in Bungoma County, Kenya

The fatty acid profile in breast milk of nursing mothers who participated in a Cohort for Vitamin A (COVA) study at the fourth and ninth month of lactation was investigated. Breast milk samples were collected by manual expression and stored at - 20°C until analysis. The fat was extracted from the milk and methylated using the American Oil Chemists’ Society (AOCS) Official Methods with modifications. The separation, identification and quantification of the fatty acid methyl esters was performed by gas chromatography coupled with mass spectrometry (GC-MS). Fat contents of human milk increased significantly between the fourth and ninth month of lactation 0.38 and 1.21 mg·mL-1 respectively;P 0.05) than the average percent of the total unsaturated FAs (48.93%). Similarly, at the 9th month the percentage average of the total saturated fatty acids (15.18%) was significantly lower (P < 0.05) than the average percent of the total unsaturated FAs (31.05%). The results obtained in this study demonstrated that the fat content in breast milk significantly increased in the 9th compared to the 4th month of lactation. The fatty profile was also significantly different with the omega 6 being the dominant at the 9th month compared with the omega - 9 being dominant at the 4th month of lactation.

Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization

A palm fatty acid distillate （PFAD） has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst （SGAC） was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology （RSM）. The optimum reaction conditions were： 12.2：1 methanol-to- PFAD molar ratio, 2.9% catalyst concentration and 134 rain of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5% of the free fatty acid （FFA） conversion with 92.4% of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards.

Relationship Between Microbial Community and Soil Properties During Natural Succession of Abandoned Agricultural Land

The changes of microbial biomass carbon (MBC) and nitrogen (MBN) and microbial community in the topsoil of the abandoned agricultural land on the semi-arid Loess Plateau in China during the natural succession were evaluated to understand the relationship between microbial community and soil properties. MBC and MBN were measured using fumigation extraction, and microbial community was analyzed by the method of fatty acid methyl ester (FAME). The contents of organic C, total N, MBC, MBN, total FAME, fungal FAME, bacterial FAME and Gram-negative bacterial FAME at the natural succession sites were higher than those of the agricultural land, but lower than those of the natural vegetation sites. The MBC, MBN and total FAME were closely correlated with organic C and total N. Furthermore, organic C and total N were found to be positively correlated with fungal FAME, bacterial FAME, fungal/bacterial and Gram-negative bacterial FAME. Natural succession would be useful for improving soil microbial properties and might be an important alternative for sustaining soil quality on the semi-arid Loess Plateau in China.

Ethanol Evaporation Characteristics of the Blends of Fatty Acid Methyl Ester and Ethanol

The evaporation characteristics of fatty acid methyl ester(FAME)mixed with four concentrations of ethanol at 873 K and normal atmospheric pressure are studied herein.FAME is used as base oils,and et hanol mass fractions vary from 10%,20%,30%to 40%。The experimental results show that the evaporation process of the binary component droplets of FAME-ethanol can be divided into two stages:a fuctuation evaporation stage,and an equilibrium evaporation stage.In these four concentration gradients,micro-explosions occur in the droplet evaporation process.The fuctuation evaporation stage is divided into two stages:a strong fuctuation stage and a weak fluctuation stage.After the micro-explosion,there is still a small amount of ethanol in the droplet.Due to the surface tension of the droplet,a small amount of ethanol cannot make the droplet violently fuctuate.The results show that the earlier the droplet micro-explosion occurs,the more intense it is,and the shorter the lifetime of the droplet is.Different concentrations of ethanol have different improvements in droplet evaporation characteristics.Generally,the higher the ethanol concentration is,the shorter the lifetime of the droplet is.However,increasing the ethanol concentration from 20%to 30%has the most obvious effect on the lifetime of the droplet.

Livestock Antibiotic Effects on Nitrification, Denitrification, and Microbial Community Composition in Soils

The broiler (Gallus gallus domesticus) industry in the United States and several other countries routinely includes subtherapeutic levels of antibiotics such as roxarsone, virginiamycin, and bacitracin in the feed to improve bird growth yields. Large fractions of the antibiotics fed to the birds are excreted in manure (litter), which is often applied to soils to improve fertility. Some concerns with this practice are antibiotic-induced alterations in microbially-mediated nutrient cycling, which could influence plant productivity and environmental quality. To investigate this possibility, a series of lab experiments were conducted to determine the effects of increasing levels of the three livestock antibiotics on nitrification, denitrification, and microbial community composition (fatty acid methyl ester profiles) of soils collected along a catena. Roxarsone and virginiamycin significantly influenced microbial community composition and inhibited nitrification in the soils, but only at levels that were several-fold higher than expected in poultry litter-applied soils. Bacitracin did not affect microbial growth, microbial community composition, or nitrification at any concentration tested (up to 500 mg·kg-1). None of the antibiotics influenced denitrification at environmentally-relevant concentrations. Amounts of antibiotics in soil solution were greatly reduced by sorption, which followed Freundlich models in the concentration range of 1 -?500 mg·L-1. Results from this study indicated that addition of roxarsone, virginiamycin, or bacitracin to these soils at environmentally-relevant concentrations would not likely impact microbial community composition, nitrification or denitrification due to intrinsic resistance/insensitivity of microorganisms to these antibiotics and reductions in the bioavailable amounts due to sorption by soil surfaces.

Synthesis and Characterisation of a Biolubricant from Cameroon Palm Kernel Seed Oil Using a Locally Produced Base Catalyst from Plantain Peelings

Biolubricant was synthesized from Cameroon palm kernel oil (PKO) by double transesterification, producing methyl esters in the first stage which were then transesterified with trimethylolpropane (TMP) to give the PKO biolubricant in the presence of a base catalyst obtained from plantain peelings (municipal waste). The yields from both catalysts were significantly similar (48% for the locally produced and 51% for the conventional) showing that the locally produced catalyst could be valorized. The synthesized biolubricant was characterized by measuring its physical and chemical properties. The specific gravity of 1.2, ASTM color of 1.5, cloud point of 0°C, pour point of -9°C, viscosities at 40°C of 509.80 cSt and at 100°C of 30.80 cSt, viscosity index of 120, flash point greater than 210°C and a fire point greater than 220°C were obtained. This synthesized biolubricant was found to be comparable to commercial T-46 petroleum lubricant sample produced industrially from mineral sources. We have therefore used local materials to produce a biolubricant using a cheap base catalyst produced from municipal waste.

Waste Cooking Oil as a Substrate for Biodiesel Production

The effectiveness of adsorptive treatment of waste cooking oils was assessed in terms of suitability for biodiesel production. New technologies involving standard diesel engines have been developed using biofuel products from vegetable oils and waste animal fats based on environmental and economic considerations. The potential application of used rapeseed oil after treatment with a mixture of active carbon （AR） and magnesium silicate （MG） as energy source was studied. The results were compared with substrates standard in the Vogel＆Noot GmbH technology for the transesterification of oils and fats.

Renewable Diesel Fuel from Processing of Vegetable Oil in Hydrotreatment Units: Theoretical Compliance with European Directive 2009/28/EC and Ongoing Projects in Spain

Oil hydrotreating units in refineries are aimed at reducing the sulfur content of fuels to accomplish standard par-ticular specifications. However, this process is currently one of the best available technologies to produce biofuels from vegetable oil in a refinery. Vegetable oils can be processed or co-processed in these units if several adaptations are performed, so some properties could be improved in comparison with conventional fuel such as density and cetane number. This study highlights the theoretical greenhouse gases (GHG) emissions (using a life cycle assessment–LCA-approach) of a hydrotreated vegetable oil (HVO) from bibliographical data. Results were compared with other biofuel production processes, such as those obtained by transesterification of vegetable oil (FAME, fatty acid methyl ester). It has also been included the comparison with conventional fossil diesel as a benchmark in order to assess the theoretical compliance with GHG savings proposed in European Directive 2009/28/EC. Finally, ongoing projects and future perspectives in Spain are mentioned.

Development of Technology for Producing a Fat Composition Based on Ester for Fattening Leather

An ester based on the secondary and by-products of oil and fat and alcohol hydrolysis is obtained for fattening the skin. Distilled fatty acids are used as a secondary product for the preparation of the ester, and fusel oil as a by-product. The main physicochemical properties of the ester obtained were determined. An ester-based formulation has been developed to fatten clothing skins from fine raw materials. The recommended is technological scheme of obtaining a composition for fattening leather.

Soil microbial activities and community diversity during the rhizoremediation of a pyrene contaminated soil

A greenhouse pot experiment was conducted to evaluate pyrene degradation, microbial biomass, basal soil respiration, metabolic quotient （qCO2）, soil enzyme activities, and the FAME patterns of rhizospheric soil and nonrhizospheric soil. The results showed that the pyrene concentrations in soil decreased with time extending and were very significant less in rhizospheric soil grown with maize plants （p〈0.01）. At the end of the 45-day experiment, the ratios of pyrene degradation were 61.25% and 35.58% in rhizospheric and nonrhizospheric soil, respectively. Maize enhanced the decrease of pyrene concentration and increased the degradation rate of pyrene in soil. During the experimental period, a relatively large amount of microbial biomass biomass （Craig）, basal soil respiration, the Cmic/Corg ratio, enzyme （urease, dehydrogenase, polyphenol oxidase, and catalase） activities were detected in rbizospheric soil. Metabolic quotient was lower in rhizospheric soil than in nonrhizospheric soil at the whole experimental period. Soil microbial communities in rhizospheric soil and nonrhizospheric soil were characterized using fatty acid methyl ester （FAME） analysis. Fatty acid profiles demonstrated that soil microbial community structure was significantly altered in pyrene contaminated soil with maize. Fatty acid indicators for fungi and the ratio of fungi to bacteria significant increased, and fatty acid indicators for bacteria and Gram-negative bacteria significantly decreased. The effect gradually increased and got very significant （p〈0.01） with the time extending. The differences of fatty acid indicators for arbuscular mycorrhizal fungi （AMF）, Gram-positive bacteria and actinomycetes gradually increased, and the differences reached significant level （p〈0.05） at the end of the experiment （45 d）.

基于脂肪酸组成结合主成分分析识别不同比例大豆油和菜籽油调配的调和油

结合脂肪酸组成和化学计量学方法,对大豆油、菜籽油及其不同比例的二元调和油的识别进行基础研究,并分析不同比例调和油中脂肪酸含量的变化。结果表明在大豆油和菜籽油中,共检出脂肪酸组分17种,主要以油酸、亚油酸、棕榈酸和亚麻酸为主。在以不同比例低芥酸菜籽油和大豆油调配的调和油中,脂肪酸含量随调和比例的改变而呈现一定趋势的增加或减小。结合脂肪酸组成,对所有的139个样品进行了主成分分析(PCA),结果表明大豆油和菜籽油可以互相实现区分,不同比例的调和油样品分布在调配的溯源样品之间,基本按照比例关系分布成一条直线。研究通过对菜籽油、大豆油及其不同比例调配的调和油的脂肪酸组成进行了定量分析,分析了它们之间脂肪酸组成的变化,并结合化学计量学手段进行一些识别分析,为规范调和油的生产和保障公平有序的调和油市场提供参考。

In Situ Transesterification of Wet Marine and Fresh Water Microalgae for Biodiesel Production and Its Effect on the Algal Residue

This article reports a high yielding technique of synthesizing zirconium dodecyl sulphate (“ZDS”) for in situ transesterification of Nannochloropsis occulata and Chlorella vulgaris for fatty acid methyl ester (FAME) production. ZDS produced a significantly higher FAME yield in N. occulata than in C. vulgaris (p = 0.008). The varying performance of ZDS in the two species could be due to their different cell wall chemistries. Sodium dodecyl sulphate (SDS) in H2SO4 for FAME enhancement from the two species was also studied. Treatment with SDS in H2SO4 increased the FAME production rate in both species. Residual protein content after the in situ transesterification in C. vulgaris and N. occulata reduced respectively by 6.5% and 10%. The carbohydrate content was reduced by 71% in C. vulgaris and 65% in N. occulata. The water tolerance of the process when using H2SO4, with or without SDS, was evaluated by hydrating the two species with 10% - 30% distilled water (w/w dry algae). The FAME concentration began to diminish only at 30% water content in both species. Furthermore, the presence of a small amount of water in the biomass or methanol increased the lipid extraction efficiency, improving the FAME yield, rather than inhibiting the reaction.

NiMoRe/HZSM-5催化剂的制备及其催化脂肪酸甲酯加氢脱氧

使用浸渍法制备了5 kg NiMoRe/HZSM-5催化剂,结合X射线衍射(XRD)、扫描电子显微镜(SEM)、电感耦合等离子原子发射光谱(ICP-OES)等表征手段对催化剂进行理化性质分析,并对该催化剂用于硬脂酸甲酯加氢脱氧反应的最佳条件进行探究。研究结果表明:相比3种商用催化剂,NiMoRe/HZSM-5中金属Ni具有较小颗粒,且分散均匀,BET比表面积(S_(BET))更大,为239.1 m^(2)/g,具有更好的催化活性。在温度260℃、0.3 g催化剂用量、反应时间4 h、初始H 2压力3 MPa的最优反应条件下,原料转化率和烷烃选择性均为100%,且催化剂稳定性较佳,第5次循环原料转化率仍高达96.1%,加氢脱氧(HDO)反应的选择性(S HDO/DCO),即HDO反应与脱羧脱羰(DCO)反应的比值由1.2降至0.56。将催化剂NiMoRe/HZSM-5用于脂肪酸甲酯无溶剂条件下的加氢脱氧反应放大实验后进行中试,采用2.8 L固定床对25 kg脂肪酸甲酯进行连续加氢性能评价,经过15循环后脂肪酸甲酯的转化率达到98%。