Kinetics of oxirane cleavage in epoxidized soybean oil

Zaher, F. A.; El-Mallah, M. Hassan; El-Hefnawy, M. M.

doi:10.1007/bf02669955

Cited by 68 publications

(62 citation statements)

References 7 publications

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“…From the results, it is confirmed that the epoxidation rate mainly depends on the formation rate of PAA which reacts with ethylenic unsaturation in the successive steps. SO 4 In the presence of AIER Iodine value Soybean oil [17] 18.3 -130 Palm Olein [6] 14.8 --Vegetable oil [16] -1 1 . 6 -Rubber seed oil [4] 15.7 -120 Karanja oil [18,19] 14.…”

Section: Activation Energy Of Epoxidation For Various Oil Systemsmentioning

confidence: 99%

Selective epoxidation of natural triglycerides using acidic ion exchange resin as catalyst

Dinda

Goud

Patwardhan

et al. 2011

Asia-Pacific J Chem Eng

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Epoxidation is a very useful reaction in organic synthesis. Due to the high reactivity of the epoxide group it can be used as an active intermediate for the synthesis of many high-value products. Epoxides are commercial products and they have many industrial uses. Understanding the kinetics of epoxidation reactions can lead to production of value-added products from locally available renewable natural resources. This research investigated the kinetics of epoxidation of cottonseed oil by peroxyacetic acid (PAA) generated in situ from hydrogen peroxide and glacial acetic acid (AA) in the presence of acidic ion exchange resin (AIER) catalysts, namely Amberlite IR-120. The effect of several variables including temperature, stirring speed, catalyst loading, and particle size, concentration of hydrogen peroxide and AA on oxirane conversion was studied. A satisfactory level of oxirane conversion (greater than 65%) with high selectivity (greater than 90%) could be obtained if the epoxidation was carried out at optimum conditions, using in situ generated PAA. The Langmuir-Hinshelwood-Hougen-Watson (L-H-H-W) kinetic model approach has been adopted for the development of overall reaction rate equations, and the proposed kinetic model includes the major side reactions for the estimation of kinetic parameters. Kinetic parameters were estimated by fitting experimental data using a nonlinear regression method. From the estimated kinetic constants, the activation energy for the AIER catalysed epoxidation of cottonseed oil was found to be 10.1 kcal mol −1 . 

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Section: Activation Energy Of Epoxidation For Various Oil Systemsmentioning

confidence: 99%

Selective epoxidation of natural triglycerides using acidic ion exchange resin as catalyst

Dinda

Goud

Patwardhan

et al. 2011

Asia-Pacific J Chem Eng

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“…The rate constants obtained for the reaction were in the range 0.22-69.4 × 10 −6 l.mol −1 .s −1 (Table 5), and in agreement with the values reported for MEPOL, soybean oil, cottonseed oil, mahua oil, and karanja oil. [22,23,27,32,35,36] Activation energy for the in situ epoxidation of JO obtained from the Arrhenius plot are shown in [22,23,27,33,35] …”

Section: Epoxidation Kineticsmentioning

confidence: 99%

Epoxidation of Jatropha (Jatropha curcas) oil by peroxyacids

Goud

Dinda

Patwardhan

et al. 2009

Asia-Pacific J Chem Eng

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Jatropha (Jatropha curcas) oil with iodine value 104 g I 2 /100 g, and containing 44.7% oleic acid and 31.4% linoleic acid, was epoxidised in situ with hydrogen peroxide (30%) and acetic/formic acid in the presence of catalytic amounts of sulphuric acid. We have compared the kinetics of epoxidation of jatropha oil (JO) by peroxyacetic and peroxyformic acids, in or without toluene at 30, 50, 70, and 85• C. The effects of temperature and various mole ratios on epoxidation rate, oxirane ring stability, and iodine value of the epoxidised oil were studied, and optimum conditions were established. The rate constants for epoxidation of JO were found to be in the range 0.22-69.4 × 10 −6 l.mol −1 .s

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“…The oxirane ring-opening reactions are irreversible, and so they are always favored by temperature rises. The value of E a is within the range of the activation energy found in liquid-liquid systems by Zaher et al (66.30 kJ mol 21 -using glacial AA) [9] and the calculated one by us in our study of the opening of the oxirane ring with solvated acetic acid employing sulfuric acid as homogeneous catalyst, 51.32 kJ mol 21 [12].…”

mentioning

confidence: 67%

“…Until recently, the only oxirane ring-opening reaction studies related to middle-or long-chain epoxides obtained from VO and/or FAME addressed the impact of carboxylic acids (formic, acetic or heptanoic), pure or in organic phase exclusively [8][9][10][11]. Under realistic process conditions, though, the reactants and intermediate products are solvated.…”

Section: Figmentioning

confidence: 99%

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Degradation of the oxirane ring of epoxidized vegetable oils with solvated acetic acid using cation‐exchange resins

Campanella

Baltanás

2004

Euro J Lipid Sci & Tech

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Degradation of the oxirane ring of epoxidized vegetable oils with solvated acetic acid using cation-exchange resinsVegetable oil epoxides (oxiranes) are customarily manufactured using acetic acid (AA) as oxygen carrier and reactant source, in aqueous/organic media. Further attack of the oxirane ring by AA proceeds in this acid-catalyzed process, lowering yield. We report a study of the degradation of the ring by water-solvated AA, using Amberlite IR-120 as heterogeneous catalyst. The ring opening with solvated AA was found to be first order with respect to the concentration of epoxide groups and second order with respect to the carboxylic acid, with an activation energy of 58.7 6 0.42 kJ mol 21. This value is within the range found in liquid-liquid systems (51.3-66.3 kJ mol 21). Yet, using IR-120, the degradation increases identically either by adding more mass of catalyst or by reducing its particle diameter while keeping the total mass constant, as both situations lead to higher external (exposed) area of the acidic catalyst (i.e., free protons associated to the sulfonic group) on the outer surface of the ion exchange resin beads. These free protons, in turn, become available to catalyze the attack on the oxirane groups of the long-chain fatty acids, which cannot enter (diffuse) into the gel phase of the resin. Despite the unavoidable presence of surface-exposed protons, the degradation can be reduced by several orders of magnitude -for similar process conditionsby using this type of heterogeneous catalysts instead of mineral acids.

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Kinetics of oxirane cleavage in epoxidized soybean oil

Cited by 68 publications

References 7 publications

Selective epoxidation of natural triglycerides using acidic ion exchange resin as catalyst

Selective epoxidation of natural triglycerides using acidic ion exchange resin as catalyst

Epoxidation of Jatropha (Jatropha curcas) oil by peroxyacids

Degradation of the oxirane ring of epoxidized vegetable oils with solvated acetic acid using cation‐exchange resins

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