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Search Results: 1 - 10 of 3231 matches for " Bashar Mudhaffar Abdullah "
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Optimization of Process Variables using D-optimal Design for Separating Linoleic acid in Jatropha curcas Seed Oil by Urea Complex Fractionation
Bashar Mudhaffar Abdullah,Jumat Salimon
Biotechnology , 2010,
Abstract: Linoleic Acid (LA) from a mixture of free fatty acids obtained from local Jatropha curcas seed oil was separated using urea complex fractionation. In this study, variations of factors that affect the urea complex fractionation such as the ratio of urea to free fatty acid, crystallization temperature and crystallization time were examined to obtain optimum condition using response surface method (D-optimal design). Under the optimal conditions, the percentage of LA was 92.81 and the percentage of yield of NUCF 7.8 at urea/FFA ratio (w/w) 5, a crystallization temperature of -10°C and a crystallization time 24 h. This showed that the experimental conditions should be suitable for the preparation of high purity LA. Performing the experiment at this condition gave results that were close to the predicted values.
Epoxidation of Vegetable Oils and Fatty Acids: Catalysts, Methods and Advantages
Bashar Mudhaffar Abdullah,Jumat Salimon
Journal of Applied Sciences , 2010,
Abstract: This study has attempted to show the efficiency of epoxidation under different catalysts conditions. It was found that different catalysts have been used for epoxidation of oil and unsaturated fatty acid with almost complete conversion and mono-epoxide of unsaturated carbon. Catalysts such as H2SO4, Ti(IV)-grafted silica catalysts, tungsten-based catalyst, acidic ion, exchange resin, potassium peroxomonosulfate, alumina-catalzed have been studied. H2SO4 was found to be more effective in terms of oxirane complete conversion. The epoxidation of oils and unsaturated fatty acids is widely used for the production of oxiranes, valuable industrial products providing an access to various fine chemicals but none has yet found industrial application. The application of different catalysts enables the preparation of a number of epoxy compounds impossible to obtain by other methods, or considerable improvement of the yields of those currently studied.
Diesters Biolubricant Base Oil: Synthesis, Optimization, Characterization, and Physicochemical Characteristics
Jumat Salimon,Nadia Salih,Bashar Mudhaffar Abdullah
International Journal of Chemical Engineering , 2012, DOI: 10.1155/2012/896598
Abstract: Diesters biolubricant base oil, oleyl 9(12)-hydroxy-10(13)-oleioxy-12(9)-octadecanoate (OLHYOOD) was synthesized based on the esterification reaction of 9,12-hydroxy-10,13-oleioxy-12-octadecanoic acid (HYOOA) with oleyl alcohol (OL) and catalyzed by sulfuric acid (SA). Optimum conditions of the experiment to obtain high yield % of OLHYOOD were predicted at ratio of OL/HYOOA of 2?:?1?mol/mol, ratio of SA/HYOOA of 0.7?:?1?mol/mol, reaction temperature 110°C, and 7?h of reaction time. At this condition, the yield of OLHYOOD was 88.7%. Disappearance of carboxylic acid (C=O) peak has been observed by FTIR with appearance of ester (C=O) peak at 1738?cm?1. 13C, and 1H?NMR spectra analyses confirmed the result of OLHYOOD with the appearance of carbon-ester (C=O) chemical shift at 173.93?ppm and at 4.05?ppm for 13C and 1H?NMR, respectively. The physicochemical characteristics of the OLHYOOD were also determined, which showed improved low temperature properties (PP) ?62°C, viscosity index (VI) at 192 and also increased oxidative stability (OT) up to 215.24°C. 1. Introduction Oleochemicals that are derived from natural fats and oils are referred to as natural oleochemicals [1]. Industrially, most fatty acids are obtained from animal or vegetable sources. It is possible to produce several industrial products from fatty acids (saturated and unsaturated). Fatty acid products have different utilization as resins, plastics, perfumes, coatings, flavors, cosmetics, solvents, soaps, medicinals, biofuels, and biolubricants [2]. Synthetic biolubricant based on renewable resources are important in developing environmentally acceptable lubricating oils [3]. Currently, lubricant-based petroleum worldwide end up in the environment via total loss applications, spills, or major accidents. A fact remains that about 3 million tones are lost in the European environment every year originating from loss and high-risk lubricants mostly based on mineral oil. Emissions of mineral oil may appear to be negligible importance compared to an accident involving an oil tanker spill [4]. And also, the emissions of mineral oil arising from lubricant applications in water make lubricants contribution to the pollution of water much more significant [5]. In the last decade, a lot of interest was developed to use environmental friendly biolubricant fluids [6]. The use of environmentally acceptable vegetable-oil-based product as biolubricants has many advantages. They are nontoxic, biodegradable, derived from renewable resource and have a reasonable cost when compared to other synthetic fluids [7].
Saponification of Jatropha curcas Seed Oil: Optimization by D-Optimal Design
Jumat Salimon,Bashar Mudhaffar Abdullah,Nadia Salih
International Journal of Chemical Engineering , 2012, DOI: 10.1155/2012/574780
Abstract: In this study, the effects of ethanolic KOH concentration, reaction temperature, and reaction time to free fatty acid (FFA) percentage were investigated. D-optimal design was employed to study significance of these factors and optimum condition for the technique predicted and evaluated. The optimum conditions for maximum FFA% were achieved when 1.75?M ethanolic KOH concentration was used as the catalyst, reaction temperature of and reaction time of 2.0?h. This study showed that ethanolic KOH concentration was significant variable for saponification of J. curcas seed oil. In an 18-point experimental design, percentage of FFA for saponification of J. curcas seed oil can be raised from 1.89% to 102.2%. 1. Introduction Saponification of oils is the applied term to the operation in which ethanolic KOH reacts with oil to form glycerol and fatty acids. Production of fatty acid and glycerol from oils is important especially in oleochemical industries. Glycerol and fatty acids are widely used as raw materials in food, cosmetics, pharmaceutical industries [1, 2], soap production, synthetic detergents, greases, cosmetics, and several other products [3]. The soap production starting from triglycerides and alkalis is accomplished for more than 2000 years by [4]. These reactions produce the fatty acids that are the starting point for most oleochemicals production. As the primary feedstocks are oils and fats, glycerol is produced as a valuable byproduct. Reaction routes and conditions with efficient glycerol recovery are required to maximize the economics of large-scale production [5]. Lipid saponification is usually carried out in the laboratory by refluxing oils and fats with different catalysts [6]. The reaction can be catalyzed by acid, base, or lipase, but it also occurs as an uncatalyzed reaction between fats and water dissolved in the fat phase at suitable temperatures and pressures [7]. Researchers have used several methods to saponify oils such as enzymatic saponification using lipases from Aspergillus niger, Rhizopus javanicus, and Penicillium solitum [8], C. rugosa [1], and subcritical water [3]. Historically, soaps were produced by alkaline saponification of oils and fats, and this process is still referred to as saponification. Soaps are now produced by neutralization of fatty acids produced by fat splitting, but alkaline saponification may still be preferred for heat-sensitive fatty acids [9]. Nowadays, researchers have used potassium hydroxide-catalyzed hydrolysis of esters which is sometimes known as saponification because of its relationship with soap
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.
Production of Chemoenzymatic Catalyzed Monoepoxide Biolubricant: Optimization and Physicochemical Characteristics
Jumat Salimon,Nadia Salih,Bashar Mudhaffar Abdullah
Journal of Biomedicine and Biotechnology , 2012, DOI: 10.1155/2012/693848
Abstract: Linoleic acid (LA) is converted to per-carboxylic acid catalyzed by an immobilized lipase from Candida antarctica (Novozym 435). This per-carboxylic acid is only intermediate and epoxidized itself in good yields and almost without consecutive reactions. Monoepoxide linoleic acid 9(12)-10(13)-monoepoxy 12(9)-octadecanoic acid (MEOA) was optimized using D-optimal design. At optimum conditions, higher yield% (82.14) and medium oxirane oxygen content (OOC) (4.91%) of MEOA were predicted at 15 μL of H2O2, 120 mg of Novozym 435, and 7 h of reaction time. In order to develop better-quality biolubricants, pour point (PP), flash point (FP), viscosity index (VI), and oxidative stability (OT) were determined for LA and MEOA. The results showed that MEOA exhibited good low-temperature behavior with PP of ?41°C. FP of MEOA increased to 128°C comparing with 115°C of LA. In a similar fashion, VI for LA was 224 generally several hundred centistokes (cSt) more viscous than MEOA 130.8. The ability of a substance to resist oxidative degradation is another important property for biolubricants. Therefore, LA and MEOA were screened to measure their OT which was observed at 189 and 168°C, respectively.
Selectively increasing of polyunsaturated (18:2) and monounsaturated (18:1) fatty acids in Jatropha curcas seed oil by crystallization using D-optimal design
Jumat Salimon, Bashar Mudhaffar Abdullah, Nadia Salih
Chemistry Central Journal , 2012, DOI: 10.1186/1752-153x-6-65
Abstract: Optimum conditions of the experiment to obtain maximum concentration of LA were predicted at urea-to-FAs ratio (w/w) of 5:1, crystallization temperature of ?10°C and 24 h of crystallization time. Under these conditions, the final non-urea complex fraction (NUCF) was predicted to contain 92.81% of LA with the NUCF yield of 7.8%. The highest percentage of OA (56.01%) was observed for samples treated with 3:1 urea-to-FAs ratio (w/w) at 10°C for 16 h. The lowest percentage of LA (8.13%) was incorporated into urea complex fraction (UCF) with 1:1 urea-to-FAs ratio (w/w) at 10°C for 8 h.The separation of PUFA (LA) and MUFA (OA) described here. Experimental variables should be carefully controlled in order to recover a maximum content of PUFA and MUFA of interest with reasonable yield% with a desirable purity of fatty acid of interest.Linoleic acid (LA) [also called cis,cis,-9,12-octadecadienoic acid] is an example of a polyunsaturated fatty acid (PUFA), due to the presence of two carbon double bonds. The high content of LA makes Jatropha curcas seed oil very important for industry use. LA can be used in protective coatings, plastics, surfactant, dispersants, biolubricant, and a variety of synthetic and in the preparations of other long chain compounds. The high content of LA in seed oil of J. curcas is very important to the production of oleo-chemicals [1]. Oleic acid (OA) [also called (9z)- octadec-9-enoic acid] is an example of a monounsaturated fatty acid (MUFA). A small amount of OA is used in the pharmaceutical industry, as an emulsifying agent in aerosol products [2].There are several methods which can be used to obtain polyunsaturated fatty acids (PUFA) including freezing crystallization, urea complexation, molecular distillation, supercritical fluid extraction, silver ion complexation and lipase concentration [3] as well as high-performance liquid chromatography [4]. The most economic and most efficient technique to obtain LA in the form of fatty acids (FAs) is ure
Synthesis and Physical Properties of Estolide Ester Using Saturated Fatty Acid and Ricinoleic Acid
Jumat Salimon,Neeranjini Nallathamby,Nadia Salih,Bashar Mudhaffar Abdullah
Journal of Analytical Methods in Chemistry , 2011, DOI: 10.1155/2011/263624
Abstract: A study was conveyed to produce estolide ester using ricinoleic acid as the backbone. The ricinoleic acid reacted with saturated fatty acid from C8–C18. These reactions were conducted under vacuum at 60°C for 24?h without solvent. The reaction used acid catalyst, sulphuric acid. The new saturate ricinoleic estolide esters show superior low-temperature properties (?52 ± 0.08°C) and high flash point (>300°C). The yield of the neat estolide esters ranged from 52% to 96%. The viscosity range was 51 ± 0.08 to 86 ± 0.01?cp. These new saturated estolide esters were also compared with saturated branched estolide esters. 1. Introduction Castor bean oil contains ricinoleic acid, a hydroxy monounsaturated fatty acid as main constituent of its fatty acid profile. Ricinoleic acid, cis-12-hydroxy-9-octadecenoic acid, has an unusual polarity due to position of hydroxyl group [1]. Castor oil is the only commercially available vegetable oil containing hydroxy functionality of a fatty acid present abundantly (70–90%) [2]. Ricinoleic acid can undergo a wide range of reactions enabling formation of several derivatives. Its various derivatives like ricinoleyl alcohol, methyl ricinoleate, azelaic acid, and ricinenic acid are used as plasticizer and emulsifier [3]. Ricinoleic acid derivatives are used in pigment, printing ink, and textile finishing. However, its main use is as chemical intermediate to produce various oleochemicals. Estolides and estolide esters from castor oil, or any source of hydroxy fatty acids [4], have been explored and show promise as cosmetics, coatings, and biodegradable lubricants. Estolides are formed when the carboxylic acid functionality of one fatty acid links to the site of unsaturation of another fatty acid to form oligomeric esters. Complex estolides have been synthesized by [5] where oleic acid and various saturated fatty acids, butyric through stearic, were treated with 0.4 equivalents of perchloric acid at either 45 or 55°C to produce a new class of saturated estolides with superior low-temperature properties. However, no journal has reported using ricinoleic acid as a starting fatty acid. The current work involves the synthesis of a new series of estolide ester from ricinoleic acid and various fatty acids. The effect of fatty acid carbon chain length on physical characterization of these estolide esters was determined. 2. Materials and Methods 2.1. Materials Castor beans from experimental plot UKM were used to extract castor oil. Concentrated sulphuric acid (98%) and potassium hydroxide (KOH) were purchased from J. T. Baker Inc. Caprylic
New photostabilizers for polystyrene based on 2,3-dihydro-(5-mercapto-1,3,4-oxadiazol-2-yl)-phenyl-2-(substituted)-1,3,4-oxazepine- 4,7-dione compounds
Emad Yousif, Ayad Hameed, Nadia Salih, Jumat Salimon and Bashar Mudhaffar Abdullah
SpringerPlus , 2013, DOI: 10.1186/2193-1801-2-104
Abstract: The photostabilization of polystyrene (PS) films by 2,3-dihydro-(5-mercapto-1,3,4-oxadiazol-2-yl)-phenyl-2-(substituted)-1,3,4-oxazepine-4,7-dione compounds was investigated. PS films containing concentration of complexes 0.5% by weight were produced by the casting method from chloroform as a solvent. The photostabilization activities of these compounds were determined by monitoring the carbonyl and hydroxyl indices with irradiation time. The changes in viscosity average molecular weight of PS with irradiation time were also tracked (using benzene as a solvent). The quantum yield of the chain scission (Phics) of these complexes in PS films was evaluated and found to range between 3.31 x 10-6 and 7.89 x 10-6. Results obtained showed that the rate of photostabilization of PS in the presence of the additive follows the trend (I > II > III > IV). According to the experimental results obtained, several mechanisms were suggested depending on the structure of the additive like UV absorption, peroxide decomposer and radical scavenger.
Optical properties of pure and modified poly(vinyl chloride)
Emad Yousif, Mustafa Abdallh, Hassan Hashim, Nadia Salih, Jumat Salimon, Bashar Mudhaffar Abdullah and Yip-Foo Win
International Journal of Industrial Chemistry , 2013, DOI: 10.1186/2228-5547-4-4
Abstract: The results showed that for all compositions, the refractive index decreases with increasing wavelength.
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