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Improvement of Physicochemical Characteristics of Monoepoxide Linoleic Acid Ring Opening for Biolubricant Base Oil
Jumat Salimon,Nadia Salih,Bashar Mudhaffar Abdullah
Journal of Biomedicine and Biotechnology , 2011, DOI: 10.1155/2011/196565
Abstract: For environmental reasons, a new class of environmentally acceptable and renewable biolubricant based on vegetable oils is available. In this study, oxirane ring opening reaction of monoepoxide linoleic acid (MEOA) was done by nucleophilic addition of oleic acid (OA) with using p-toluene sulfonic acid (PTSA) as a catalyst for synthesis of 9(12)-hydroxy-10(13)-oleoxy-12(9)-octadecanoic acid (HYOOA) and the physicochemical properties of the resulted HYOOA are reported to be used as biolubricant base oils. Optimum conditions of the experiment using D-optimal design to obtain high yield% of HYOOA and lowest OOC% were predicted at OA/MEOA ratio of 0.30 : 1 (w/w), PTSA/MEOA ratio of 0.50 : 1 (w/w), reaction temperature at 110°C, and reaction time at 4.5 h. The results showed that an increase in the chain length of the midchain ester resulted in the decrease of pour point (PP) ?51°C, increase of viscosity index (VI) up to 153, and improvement in oxidative stability (OT) to 180.94°C.
Synthesis and Characterisation of a Biolubricant from Cameroon Palm Kernel Seed Oil Using a Locally Produced Base Catalyst from Plantain Peelings  [PDF]
Michael Bong Alang, Maurice Kor Ndikontar, Yahaya Muhammad Sani, Peter T. Ndifon
Green and Sustainable Chemistry (GSC) , 2018, DOI: 10.4236/gsc.2018.83018
Abstract: 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.
The Effects of Various Acid Catalyst on the Esterification of Jatropha Curcas Oil based Trimethylolpropane Ester as Biolubricant Base Stock  [PDF]
Noor Hafizah Arbain,Jumat Salimon
Journal of Chemistry , 2011, DOI: 10.1155/2011/789374
Purification of Crude Glycerol from Transesterification RBD Palm Oil over Homogeneous and Heterogeneous Catalysts for the Biolubricant Preparation  [PDF]
W.N.R.W. Isahak,M. Ismail,M.A. Yarmo,J.M. Jahim
Journal of Applied Sciences , 2010,
Abstract: Crude glycerol samples used in this study consisted of crude glycerol (CG1) produced from homogeneous catalyst (NaOH) obtained from Golden Hope biodiesel plant and crude glycerol (CG2) as a product of heterogeneous catalysed transesterification RBD palm oil using KOH/Al2O3 catalyst. KOH/Al2O3 catalyst was produced by wet impregnation method and characterized by using BET, XRD and SEM-EDX methods. 15% KOH/ Al2O3 has BET surface area of 26.1 m2 g-1 compared with 100.4 m2 g-1 for fresh Al2O3. The first purification stage of the crude glycerol was achieved by employing the neutralization method followed by microfiltration and ion exchange resins methods. Inorganic salts as a result of the neutralization with 85% v/v phosphoric acid were filtered using syringe filter 0.45 μm. Only glycerol peak could be detected using a Dionex C-18 column in the HPLC indicating that the neutralization step enabled the removal of excess homogeneous catalyst as well as the unreacted free fatty acids in the crude glycerol samples. The free ions from salt and catalyst were then eliminated through ion exchange process using Amberlite resins to produce higher glycerol purity. The samples were also analyzed using FTIR to check on their purity level and to detect any impurity that may still exist. The products of this 3-step purification method were deemed comparable to that of a commercial pure glycerol based on the viscosity, pH value, free fatty acid value, moisture content and density rendering them as competitive feedstock for the biolubricant production.
Oleins as a source of estolides for biolubricant applications
García-Zapateiro, L. A.,Delgado, M. A.,Franco, J. M.,Valencia, C.
Grasas y Aceites , 2010, DOI: 10.3989/gya.075209
Abstract: This study deals with the synthesis of estolides from high-oleic sunflower oil oleins, and its potential use as viscosity modifiers for biolubricant applications. Synthesis reactions were monitored for 24 h. Estolide molecular weight increased continuously with reaction time. Dynamic viscosities and densities of the different estolides were measured in a temperature range comprised between 10 and 120 °C. Maximum viscosities and estolide molecular weight were obtained after 12 h of reaction. However, the largest viscosity increments were observed within the first 3 hours of processing, due to a dramatic increase in the molecular weight of the estolides. En este estudio se presenta la síntesis de estólidos a partir de oleinas de girasol alto-oleico y su utilización potencial como modificadores de la viscosidad en aplicaciones como biolubricantes. La reacción de síntesis se controló durante 24h. El peso molecular de los estólidos se incrementa durante todo el periodo de reacción. Las viscosidades dinámicas y densidades de los diferentes estólidos se midieron en un rango de temperatura entre 10 y 120 °C. El máximo de viscosidad y de peso molecular se alcanza al cabo de 12 horas de reacción, sin embargo, el incremento mayor de viscosidad se produce durante las 3 primeras horas de tratamiento debido al importante aumento del peso molecular del estólido.
Physicochemical Properties and Fatty Acid Profile of Hyptis spicigera Seed Oil
Z. Ladan,E.M. Okonkwo,J.O. Amupitan,E.O. Ladan,B. Aina
Research Journal of Applied Sciences , 2012, DOI: 10.3923/rjasci.2010.123.125
Abstract: Hyptis spicigera seed oil was characterized using GC-MS and UV-VIS spectrometry for its fatty acid composition, tocopherol content and physicochemical properties. The oil content was 21% while unsaturated fatty acids were linoleic acid (71.85%) and Palmitic acid (16.06%) as predominant fatty acids. Tocopherol content was 186.15 mg mL-1 while Vitamin A was absent. This study showed potentials of Hyptis spicigera seed oil to have high oxidative stability which could be suitable for food and beverage as well as other industrial applications while the tocopherol content could improve human health.
Protective role of onion and garlic on physicochemical alterations and toxicity of heated soybean oil
OI Oyewole, ET Olayinka
African Journal of Biotechnology , 2007,
Abstract: Fresh and soybean oil heated with or without onion or garlic were analyzed for their physicochemical and toxicological properties. Darkened appearance, off flavors, rancid taste and significant reduction of iodine value was obtained for the heated oil. Acid value, peroxide value, viscosity and concentration of malondialdehyde of the thermooxidized soybean oil were also significantly elevated (P<0.05) with considerable loss of ascorbic acid and tocopherols. Heating with onion and garlic considerably preserved the quality of the oil as indicated in the significant reduction in levels of lipid peroxidation indicators as well as reduction in loss of ascorbic acid and tocopherol. Rats fed with diet containing heated oil for a period of four weeks showed significant elevation (P<0.05) in the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) starting from the second week to the end of the experimental period. This might be as a result of cellular damage caused by peroxides and other lipid oxidation products which allowed the enzymes to leak out from the tissues. The levels of these enzymes were maintained close to the control in rats fed with diets containing heated oil with garlic and onion indicating their protective role in lipid oxidation.
Influence of the extraction method and storage time on the physicochemical properties and carotenoid levels of pequi (Caryocar brasiliense Camb.) oil
Ribeiro, Milton Cosme;Vilas Boas, Eduardo Valério de Barros;Riul, Tania Regina;Pantoja, Lílian;Marinho, Helyde Albuquerque;Santos, Alexandre Soares dos;
Ciência e Tecnologia de Alimentos , 2012, DOI: 10.1590/S0101-20612012005000053
Abstract: the objective of this study was to analyze the physicochemical properties and carotenoid levels of pequi oil obtained by different extraction methods and to evaluate the preservation of these properties and pigments during storage time. the pequi oil was obtained by solvent extraction, mechanical extraction, and hot water flotation. it was stored for over 180 days in an amber bottle at ambient conditions. analyses for the determination of the acidity, peroxide, saponification and iodine values, coloration, total carotenoids, and β-carotene levels were conducted. the oil extraction with solvents produced the best yield and carotenoid levels. the oil obtained by mechanical extraction presented higher acidity (5.44 mg koh.g-1) and peroxide values (1.07 meq.kg-1). during the storage of pequi oil, there was an increase in the acidity and the peroxide values, darkening of the oil coloration, and a reduction of the carotenoid levels. mechanical extraction is the less advantageous method for the conservation of the physicochemical properties and carotenoid levels in pequi oil.
Effect of Vegetable-Based Oil Blends on Physicochemical Properties of Oils During Deep-Fat Frying  [PDF]
Yaakob Bin Che Man,Hamed Mirhosseini,Chin Ping Tan,Alireza Serjouie
American Journal of Food Technology , 2010,
Abstract: Frying performance of palm olein, sesame oil and canola oil and their blends was investigated by assessing the physicochemical changes (i.e., color, viscosity, Free Fatty Acid (FFA), Peroxide Value (PV), Anisidine Value (AV), TOTOX Value (TV), Polymer Content (PC) and specific extinction) of oils during deep-fat frying of potato chips. Six frying oils, namely refined, bleached and deodorized (RBD) palm olein (A), canola oil (C), RBD palm olein/sesame oil (AB, 1:1 w/w), RBD palm olein/canola oil (AC, 1:1 w/w), sesame oil/canola oil (BC, 1:1 w/w) and RBD palm olein/sesame oil/canola oil (ABC, 1:1:1 w/w/w) were considered as the independent variables. The physicochemical properties of the frying oils were significantly (p<0.05) influenced by the type and concentration of the component oil(s). Among all six frying oils, canola oil (C) generally exhibited the least chemical stability during the frying process and RBD palm olein (A) the highest.
Seasonal variations of some physicochemical parameters of groundwater in crude oil flow stations
Okpokwasili G.C.,Inengite A.K.
Journal of Environmental Science and Water Resources , 2013,
Abstract: Groundwater quality monitoring of some oil locations in the Niger Delta were investigated in order to establish the influence of oil production and storage activities on the groundwater quality of these areas. Water samples were collected from groundwater monitoring boreholes, monthly for twenty four months, during the operational phase of the facilities and evaluated. Analytical techniques employed were those specified by the Department of Petroleum Resources and American Public Health Association. The physicochemical parameters analysed were temperature, pH, electrical conductivity, turbidity, chloride, total hardness, nitrate, sulphate, phosphate and dissolved oxygen. Results obtained indicated that temperature, showed no significant difference for both seasons at P<0.05 using the students t- test, while conductivity, chloride and total hardness showed significantly higher values in the dry than in the rainy season. While pH, nitrate, sulphate, phosphate, dissolved oxygen (DO) and turbidity showed higher values in the rainy than in the dry season. The mean values ranged from 24.0 to 27.90C for temperature which showed no significant difference between rainy and dry season at P<0.05 confidence limit. pH values for the groundwater ranged from 4.83 to 7.99, indicating that some locations were more acidic than the FMENV and WHO standards of 6.5 to 8.5. Conductivity ranged from 38.22 to 241.776μS/cm, chloride 7.14 to 39.17mg/l, DO 1.98 to 6.23mg/l, turbidity 0.11 to 5.45NTU and total hardness 9.06 to 64.75mg/l. The nutrient values of the samples ranged from 0.75 to 33.64mg/l for sulphate, 0.22 to 3.84mg/l for phosphate and 0.11 to 3.54mg/l for nitrate. All these were within permissible limits for domestic water acceptability. Although, the concentration of some parameters fell within the acceptable limits, these sources of water may be unacceptable for potable and industrial uses without treatment.
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