The Experts below are selected from a list of 1470 Experts worldwide ranked by ideXlab platform
Dinesh Kumar - One of the best experts on this subject based on the ideXlab platform.
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Direct synthesis of fatty acid alkanolamides and fatty acid alkyl esters from high free fatty acid containing triglycerides as lubricity improvers using heterogeneous catalyst
Fuel, 2015Co-Authors: Dinesh KumarAbstract:Abstract Direct one-step aminolysis of high free fatty acid containing triglycerides of used Cotton Seed Oil, karanja Oil and jatropha Oil was investigated using a new heterogeneous catalyst. The catalyst, 2.5-NaOH/CaO, was prepared in nanocrystalline form by using simple wet chemical method. Complete conversion of used Cotton Seed Oil (99%) to fatty alkanolamides has been obtained in 45 min with the prepared catalyst when 5 wt% of catalyst amount and 6:1 M ratio of diethanolamine/Oil were used. The catalyst was equally active for the transesterification reaction of similar feed stocks. The prepared fatty acid alkanolamides was found to improve lubricity of diesel fuel significantly.
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Sodium Impregnated Zinc Oxide as a Solid Catalyst for Biodiesel Preparation from a Variety of Triglycerides
Energy Sources Part A-recovery Utilization and Environmental Effects, 2014Co-Authors: P. Khullar, Dinesh KumarAbstract:In the present work, a series of sodium impregnated zinc oxide catalysts were prepared by a wet impregnation method followed by calcinations at different temperatures. The prepared catalysts were characterized by powder X-ray diffraction, Hammett indicator test, scanning electron, and transmission electron microscopic studies. The catalysts prepared by impregnating 5 wt% of sodium in ZnO and calcined at 400°C were used for the virgin Cotton Seed Oil transesterification with methanol. The selected catalysts were able to yield the complete transesterification of the Oil to biodiesel, and the catalytic activity was found to depend on (i) the impregnated sodium amount, (ii) the calcination temperature, (iii) methanol to Oil molar ratio, (iv) reaction temperature, and (v) the amount of free fatty acid contents in feedstock. The selected catalyst was also used for the transesterification of a variety of feedstock (virgin CottonSeed Oil, used Cotton Seed Oil, mutton fat, karanja Oil, and jatropha Oil) having fre...
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potassium ion impregnated calcium oxide as a nanocrystalline solid catalyst for biodiesel production from waste Cotton Seed Oil
Energy Sources Part A-recovery Utilization and Environmental Effects, 2014Co-Authors: Dinesh KumarAbstract:Vegetable Oil and animal fat derived fatty acid methyl esters are commonly known as biodiesel and provide an environment friendly and renewable substitute for the conventional diesel fuel. The present work demonstrates an easy preparation of potassium ion impregnated calcium oxide in nano crystalline form (supported by powder X-ray diffraction and transmission electron microscopic studies) and its application as a solid catalyst for the transesterification of waste CottonSeed Oil with methanol. The catalyst prepared by impregnating 3.5 wt% of potassium in CaO support was found to show the best catalytic activity among the prepared catalysts. The same catalyst was found to be effective for the complete transesterification of less expensive feedstock, waste Cotton Seed Oil, even in the presence of 10.26 wt% moisture and 4.35 wt% free fatty acid contents. The selected catalyst has also been reused successfully for three catalytic cycles. Few physicochemical properties of the prepared biodiesel sample have be...
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transesterification of low quality triglycerides over a zn cao heterogeneous catalyst kinetics and reusability studies
Energy & Fuels, 2013Co-Authors: Dinesh KumarAbstract:Zinc-doped (0.25–7 wt %) calcium oxide (Zn/CaO) has been prepared in nanocrystalline form by a simple wet chemical method followed by calcination up to 950 °C. The structural analysis has been investigated by powder X-ray diffraction (XRD), whereas the surface morphology and average particle size of Zn/CaO were determined by scanning electron and transmission electron microscopic studies, respectively. The catalytic activity of the prepared Zn/CaO toward the transesterification of Cotton Seed Oil with methanol was found to be a function of its calcination temperature, crystallite size, and basic strength. A pseudo-first-order kinetic model was applied to evaluate the kinetic parameters for the transesterification of waste Cotton Seed Oil with methanol, and a first-order rate constant (k) and activation energy (Ea) were found to be 0.10 min–1 and 43 kJ mol–1, respectively. The catalyst, Zn/CaO, was amenable to recovery and recycling for at least five consecutive reaction cycles. The Koros–Nowak criterion t...
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nanocrystalline lithium ion impregnated calcium oxide as heterogeneous catalyst for transesterification of high moisture containing Cotton Seed Oil
Energy & Fuels, 2010Co-Authors: Dinesh KumarAbstract:The present work demonstrates the application of nanocrystalline Li+ impregnated CaO as a heterogeneous catalyst for transesterification of used CottonSeed Oil with a higher amount of moisture. Catalysts with different alkali metal ions were prepared by the wet impregnation method, and their basic strengths were measured by Hammett indicators and a maximum was found in the case of lithium carbonate impregnated CaO. Further characterization of the lithium impregnated catalyst by powder X-ray diffraction and transmission electron microscopy studies supports the formation of a nanosized catalyst with a particle size of about 50 nm. The same catalyst has been chosen for studying the transesterification reaction of used Cotton Seed Oil with methanol. The variables used for the transesterification were impregnated alkali metal ion, percentage of Li+ impregnation, catalyst concentration, reaction temperature (35−65 °C), Oil to methanol molar ratio, reaction time (0.5−8 h), free fatty acid content (up to 6 wt %),...
Surinder P Singh - One of the best experts on this subject based on the ideXlab platform.
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genetic enhancement of palmitic acid accumulation in Cotton Seed Oil through rnai down regulation of ghkas2 encoding β ketoacyl acp synthase ii kasii
Plant Biotechnology Journal, 2017Co-Authors: Man Wu, Allan Green, Baolong Zhang, Pushkar Shrestha, James Robertson Petrie, Surinder P SinghAbstract:Summary Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional Cotton Seed Oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of Cotton Seed Oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of β-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of Cotton Seed Oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in Oil content in these high-palmitic (HP) lines, Seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.
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Genetic enhancement of palmitic acid accumulation in Cotton Seed Oil through RNAi down‐regulation of ghKAS2 encoding β‐ketoacyl‐ACP synthase II (KASII)
Plant Biotechnology Journal, 2016Co-Authors: Man Wu, Allan Green, Baolong Zhang, Pushkar Shrestha, James Robertson Petrie, Surinder P SinghAbstract:Summary Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional Cotton Seed Oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of Cotton Seed Oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of β-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of Cotton Seed Oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in Oil content in these high-palmitic (HP) lines, Seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.
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genetic modification of Cotton Seed Oil using inverted repeat gene silencing techniques
Biochemical Society Transactions, 2000Co-Authors: Surinder P Singh, Allan GreenAbstract:: Inverted-repeat-based gene constructs targeted against two key Cotton Seed-specific fatty acid desaturase genes, ghSAD-1, encoding stearoylacvl carrier protein delta9-desaturase and ghFAD2-1, encoding microsomal omega-6 desaturase, were transformed into Cotton. The expression of ghSAD-1 and ghFAD2-1 in the inverted-repeat orientation resulted in increased levels of stearic and oleic acids, respectively. Interestingly, the content of palmitic acid in both high-stearic and high-oleic lines was substantially reduced. These materials offer the promise of developing Cotton Seed Oil products with greatly improved nutritional appeal to consumers.
Allan Green - One of the best experts on this subject based on the ideXlab platform.
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genetic enhancement of palmitic acid accumulation in Cotton Seed Oil through rnai down regulation of ghkas2 encoding β ketoacyl acp synthase ii kasii
Plant Biotechnology Journal, 2017Co-Authors: Man Wu, Allan Green, Baolong Zhang, Pushkar Shrestha, James Robertson Petrie, Surinder P SinghAbstract:Summary Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional Cotton Seed Oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of Cotton Seed Oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of β-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of Cotton Seed Oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in Oil content in these high-palmitic (HP) lines, Seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.
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Genetic enhancement of palmitic acid accumulation in Cotton Seed Oil through RNAi down‐regulation of ghKAS2 encoding β‐ketoacyl‐ACP synthase II (KASII)
Plant Biotechnology Journal, 2016Co-Authors: Man Wu, Allan Green, Baolong Zhang, Pushkar Shrestha, James Robertson Petrie, Surinder P SinghAbstract:Summary Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional Cotton Seed Oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of Cotton Seed Oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed-specific RNAi-mediated down-regulation of β-ketoacyl-ACP synthase II (KASII) catalysing the elongation of palmitoyl-ACP to stearoyl-ACP has succeeded in dramatically increasing the C16 fatty acid content of Cotton Seed Oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in Oil content in these high-palmitic (HP) lines, Seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn-2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high-oleic (HO) and high-stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.
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genetic modification of Cotton Seed Oil using inverted repeat gene silencing techniques
Biochemical Society Transactions, 2000Co-Authors: Surinder P Singh, Allan GreenAbstract:: Inverted-repeat-based gene constructs targeted against two key Cotton Seed-specific fatty acid desaturase genes, ghSAD-1, encoding stearoylacvl carrier protein delta9-desaturase and ghFAD2-1, encoding microsomal omega-6 desaturase, were transformed into Cotton. The expression of ghSAD-1 and ghFAD2-1 in the inverted-repeat orientation resulted in increased levels of stearic and oleic acids, respectively. Interestingly, the content of palmitic acid in both high-stearic and high-oleic lines was substantially reduced. These materials offer the promise of developing Cotton Seed Oil products with greatly improved nutritional appeal to consumers.
K H Reddy - One of the best experts on this subject based on the ideXlab platform.
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effect of fuel injection pressures on the performance and emission characteristics of d i diesel engine with biodiesel blends Cotton Seed Oil methyl ester
International Journal of Research, 2012Co-Authors: C V S Reddy, C E Reddy, K H ReddyAbstract:The world’s rapidly dwindling petroleum supplies, their rising cost and the rapid growing of automobile pollutions from fossil petroleum fuels have led to an intensive search for alternative fuels to replace diesel fuel. Agriculture and transport sectors consume maximum percentage of petroleum based fuels where diesel engine happens to be the prime mover. Diesel fuelled vehicles discharge significant amount of pollutants such as CO, UHC, NOx, smoke, etc which are harmful to the environment. There is a wide variety of alternative fuels available as renewable fuels to replace diesel fuel. Vegetable Oils, their properties being close to diesel fuel, may be a promising alternative for use in diesel engines. The high viscosity and low volatility of these vegetable Oils are the major problems for their use in diesel engines. Such problem can be solved by the process of transesterification. In the present work, experiments are conducted on 3.72 kW(5 BHP) single cylinder, four stroke, water-cooled diesel engine using Cotton Seed Oil methyl esters blended with diesel in various proportions to study the engine performance and emissions at different injection pressures. The effect of injection pressure on the performance and emission characteristics for various biodiesel blends of 0BD, 10BD, 20BD, 30BD and 100BD at six different test pressures of 170, 180, 190, 200, 210 and 220 bar are studied. The experimental investigations reveal that the better performance and emission characteristics among the biodiesel blends are obtained at injection pressure of 200 bar with 20BD of Cotton Seed Oil methyl ester.
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effect of tangential grooves on piston crown of d i diesel engine with blends of Cotton Seed Oil methyl easter
International Journal of Research, 2012Co-Authors: C V S Reddy, C E Reddy, K H ReddyAbstract:The world’s rapidly dwindling petroleum supplies, their rising cost and the rapid growing of automobile pollutions from fossil petroleum fuels have led to an intensive search for alternative fuels to replace diesel fuel. Direct injection diesel engines are in service for both heavy duty vehicles, light duty vehicles not only in the fields of agriculture and transport sectors, but also stationary engines consume maximum percentage of petroleum based fuels and have the evident benefit of a higher thermal efficiency than all other engines. However, the direct injection diesel engine emits significant amount of pollutants such as CO, UHC, NOx, smoke etc, which are harmful to the environment. There is a wide variety of alternative fuels available as renewable fuels to replace diesel fuel. Vegetable Oils, their properties being close to diesel fuel, may be a promising alternative for use in diesel engines. The high viscosity and low volatility of these vegetable Oils are the major problems for their use in diesel engines. Such problem can be solved by the process of transesterification. In the present work experiments are conducted on D.I. Diesel engine with three different tangential grooved pistons and Cotton Seed Oil methyl esters blended with diesel in various proportions. The effect of three different sizes of tangential grooves on piston crown on the performance and emission characteristics are studied. Brake specific energy consumption decreases and thermal efficiency of engine slightly increases when operating on blended fuel of 20% Cotton Seed Oil methyl ester (COME) and 80% diesel (20BD) than that operating on diesel fuel. From the experimental investigations, it is found that 200 bar is the optimum injection pressure with 20BD blend of COME, which has resulted in better performance and emission characteristics among the biodiesel blends. Based on the results it is concluded that the base line engine with tangential grooved piston configuration(TGP-2) gives maximum performance in all aspects and reduces emissions.
N Papayannakos - One of the best experts on this subject based on the ideXlab platform.
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catalytic effect of free fatty acids on Cotton Seed Oil thermal transesterification
Industrial & Engineering Chemistry Research, 2009Co-Authors: S Pasias, Nikos K Barakos, N PapayannakosAbstract:The thermal transesterification of CottonSeed Oil with methanol has been investigated. Refined as well as Cotton Seed Oil containing 9.8 wt. % free fatty acids (FFAs) were used. The impact of the free fatty acids present in the Oil on the transesterification reaction rates has been studied. Free fatty acids were esterified in parallel with triglycerides (TGs) methanolysis reactions but their presence was beneficial for transesterification reactions as they appeared to have a catalytic effect on the monoglycerides (MGs), diglycerides (DGs), and triglycerides conversion reactions. Experiments were performed in a batch reactor in the temperature range of 170−220 °C and using a 6:1 methanol to Oil molar ratio. A kinetic model describing the thermal transesterification and esterification reaction as well as the catalytic transesterification reactions by the FFAs is presented. The proposed kinetics might also be used in transesterification processes using solid catalysts in the same temperature range to estimat...
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the effect of water on the transesterification kinetics of Cotton Seed Oil with ethanol
Chemical Engineering & Technology, 1999Co-Authors: Elena Bikou, Argiro Louloudi, N PapayannakosAbstract:A kinetic model for the transesterification of a Cotton Seed Oil with ethanol in the presence of water is proposed. The effect of water content in the reacting mixture on the transesterification reaction is studied. The dependence of the equilibrium constants and reaction rate constants on the water content is presented. Equilibrium was reached within less than 30 min reaction time in all cases. The increase of the water content results in decrease of the conversion level of the Oil. By increasing the ethanol/Oil ratio the conversion of triglyceride increases and the concentration of mono- and diglyceride in the product mixtures are reduced.
