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1.
Epoxidation of Canola Oil with Hydrogen Peroxide Catalyzed by Acidic Ion Exchange Resin 总被引:2,自引:0,他引:2
Rubeena Mungroo Narayan C. Pradhan Vaibhav V. Goud Ajay K. Dalai 《Journal of the American Oil Chemists' Society》2008,85(9):887-896
Canola oil with an iodine value of 112/100 g, and containing 60% oleic acid and 20% linoleic acid, was epoxidised using a
peroxyacid generated in situ from hydrogen peroxide and a carboxylic acid (acetic or formic acid) in the presence of an acidic
ion exchange resin (AIER), Amberlite IR 120H. Acetic acid was found to be a better oxygen carrier than formic acid, as it
produced about 10% more conversion of ethylenic unsaturation to oxirane than that produced by formic acid under otherwise
identical conditions. A detailed process developmental study was then performed with the acetic acid/AIER combination. The
parameters optimised were temperature (65 °C), acetic acid to ethylenic unsaturation molar ratio (0.5), hydrogen peroxide
to ethylenic unsaturation molar ratio (1.5), and AIER loading (22%). An iodine conversion of 88.4% and a relative conversion
to oxirane of 90% were obtained at the optimum reaction conditions. The heterogeneous catalyst, AIER, was found to be reusable
and exhibited a negligible loss in activity. 相似文献
2.
Kinetics of epoxidation of jatropha oil with peroxyacetic and peroxyformic acid catalysed by acidic ion exchange resin 总被引:1,自引:0,他引:1
Vaibhav V. Goud Srikanta Dinda Narayan C. Pradhan 《Chemical engineering science》2007,62(15):4065-4076
The kinetics of epoxidation of jatropha oil by peroxyacetic/peroxyformic acid, formed in situ by the reaction of aqueous hydrogen peroxide and acetic/formic acid, in the presence of an acidic ion exchange resin as catalyst in or without toluene, was studied. The presence of an inert solvent in the reaction mixture appeared to stabilise the epoxidation product and minimise the side reaction such as the opening of the oxirane ring. The effect of several reaction parameters such as stirring speed, hydrogen peroxide-to-ethylenic unsaturation molar ratio, acetic/formic acid-to-ethylenic unsaturation molar ratio, temperature, and catalyst loading on the epoxidation rate as well as on the oxirane ring stability and iodine value of the epoxidised jatropha oil were examined. The multiphase process consists of a consecutive reaction, acidic ion exchange resin catalysed peroxyacid formation followed by epoxidation. The catalytic reaction of peroxyacetic/peroxyformic acid formation was found to be characterised by adsorption of only acetic (or formic) acid and peroxyacetic/peroxyformic acid on the active catalyst sites, and the irreversible surface reaction was the overall rate determining step. The proposed kinetic model takes into consideration two side reactions, namely, epoxy ring opening involving the formation of hydroxy acetate and hydroxyl groups and the reaction of the peroxyacid and epoxy group. The kinetic and adsorption constants of the rate equations were estimated by the best fit using nonlinear regression method. Good agreement between experimental and predicted data validated the proposed kinetic model. From the estimated kinetic constants, the apparent activation energy for epoxidation reaction was found to be 53.6 kJ/mol. This value compares well with those reported by other investigators for the same reaction over similar catalysts. 相似文献
3.
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. 相似文献
4.
Kinetics of in situ epoxidation of soybean oil in bulk catalyzed by ion exchange resin 总被引:1,自引:0,他引:1
Snežana Sinadinović-Fišer Milovan Janković Zoran S. Petrović 《Journal of the American Oil Chemists' Society》2001,78(7):725-731
The kinetics of the epoxidation of soybean oil in bulk by peracetic acid formed in situ, in the presence of an ion exchange resin as the catalyst, was studied. The proposed kinetic model takes into consideration
two side reactions of the epoxy ring opening involving the formation of hydroxy acetate and hydroxyl groups as well as the
reactions of the formation of the peracid and epoxy groups. The catalytic reaction of the peracetic acid formation was characterized
by adsorption of only acetic acid and peracetic acid on the active catalyst sites, and irreversible surface reaction was the
overall rate-determining step. Kinetic parameters were estimated by fitting experimental data using the Marquardt method.
Good agreement between the calculated and experimental data indicated that the proposed kinetic model was correct. The effect
of different reaction variables on epoxidation was also discussed. The conditions for obtaining optimal epoxide yield (91%
conversion, 5.99% epoxide content in product) were found to be: 0.5 mole of glacial acetic acid and 1.1 mole of hydrogen peroxide
(30% aqueous solution) per mole of ethylenic unsaturation, in the presence of 5 wt% of the ion exchange resin at 75°C, over
the reaction period of 8 h. 相似文献
5.
Epoxidation of karanja (Pongamia glabra) oil by H2O2 总被引:1,自引:0,他引:1
Vaibhav V. Goud Narayan C. Pradhan Anand V. Patwardhan 《Journal of the American Oil Chemists' Society》2006,83(7):635-640
Epoxidation of karanja oil (KO), a nondrying vegetable oil, was carried out with peroxyacetic acid that was generated in situ from aqueous hydrogen peroxide and glacial acetic acid. KO contained 61.65% oleic acid and 18.52% linoleic acid, respectively,
and had an iodine value of 89 g/100 g. Unsaturated bonds in the oil were converted to oxirane by epoxidation. Almost complete
epoxidation of ethylenic unsaturation was achieved. For example, the iodine value of the oil could be reduced from 89 to 19
by epoxidation at 30°C. The effects of temperature, hydrogen peroxide-to-ethylenic unsaturation ratio, acetic acid-to-ethylenic
unsaturation ratio, and stirring speed on the epoxidation rate and on oxirane ring stability were studied. The rate constant
and activation energy for epoxidation of KO were 10−6 L·mol−1·s−1 and 14.9 kcal·mol−1, respectively. Enthalpy, entropy, and free energy of activation were 14.2 kcal·mol−1, −51.2 cal·mol−1·K−1, and 31.1 kcal·mol−1, respectively. The present study revealed that epoxides can be developed from locally available natural renewable resources
such as KO. 相似文献
6.
A. Upendrarao T. Chandrasekhararao R. Subbarao 《European Journal of Lipid Science and Technology》1972,74(4):223-226
Various acetoxy and epoxy derivatives of castor, safflower and linseed oils individually and in blends were prepared. Castor oil, two mixtures of castor and safflower oils (1 : 1 and 1 : 2, v/v) and two mixtures of castor and linseed oils (1 : 1 and 1 : 3, v/v) were first acetylated and then epoxidised by the comparatively best epoxidation method, i.e. in situ epoxidation technique using 60% hydrogen peroxide and the acid-form of Amberlite-120 resin (C. G.) as catalyst. Linseed oil was partially epoxidised to different products having various degrees of residual unsaturation, namely I. V. 98.3, 120.8 and 145.5. The partially epoxidised products were hydrogenated to yield unsaturated hydroxy compounds, protecting the unsaturation by cupric nitrate, and, the resulting unsaturated hydroxy glycerides were acetylated and further epoxidised by the in situ epoxidation method. Thus, various glycerides with varying ratios of acetoxy and epoxy groups were prepared and characterised for the use as stabilizers and plasticizers for PVC resins. 相似文献
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8.
以葵花籽油为原料,在冰醋酸和过氧化氢的共同作用下进行环氧化,制备葵花籽油基环氧化产物(SOEP);再以氢氧化锂为催化剂与二乙醇胺发生环氧开环反应,制备得到葵花籽油基多元醇(SOPOL)。探讨了反应温度和时间、冰醋酸/过氧化氢摩尔比对SOEP和SOPOL性能的影响,并采用核磁共振表征了SOEP和产物SOPOL的结构。结果表明,制备SOEP较为理想的反应温度为65℃,反应时间为10 h,葵花籽油(以双键计)、冰醋酸与过氧化氢的摩尔比为1∶2∶4;在135℃进行环氧基开环反应制备的SOPOL羟值可达到176 mgKOH/g,平均官能度为4.2。该SOPOL可替代传统石油基多元醇合成生物基聚氨酯树脂。 相似文献
9.
Eugeniusz Milchert Anna Smagowicz 《Journal of the American Oil Chemists' Society》2009,86(12):1227-1233
The influence of reaction parameters on the epoxidation of rapeseed oil (RO) with peracetic acid obtained in situ from the
reaction between 30 wt% hydrogen peroxide and glacial acetic acid (AA) has been studied. The course of the reaction was measured
by changes of the iodine number (IN) and epoxy number (EN), used to estimate the degree of rapeseed oil conversion, yield,
and the selectivity of transformation to epoxidized rapeseed oil in relation to the total amount of oil undergoing the transformation.
The optimal conditions of epoxidation are as follows: temperature 60 °C, molar ratio of hydrogen peroxide to rapeseed oil
9.5:1 mol/mol, molar ratio of acetic acid to rapeseed oil 1.12:1 mol/mol, stirring speed 500 rpm, and reaction time of 4 h.
Under these conditions the epoxy number is equal to 0.157 mol/100 g RO and iodine number reaches low values of 0.123 mol/100 g
RO. The selectivity of transformation to epoxidized RO calculated from EN and IN is 82.2%, conversion of hydrogen peroxide
is 100%, conversion of RO calculated from IN is 60.8%, and yield of RO calculated from EN is 50%. 相似文献
10.
The lipase Candida antarctica (Novozyme 435) immobilized on acrylic resin was used as an unconventional catalyst for in situ epoxidation of soybean oil. The reactions were carried out in toluene. The peracid used for converting TG double bonds to
oxirane groups was formed by reaction of FFA and hydrogen peroxide. The reaction conditions were optimized by varying the
lipase concentration, solvent concentration, molar ratio of hydrogen peroxide to double bond, oleic acid concentration, and
reaction temperature. The kinetic study showed that 100% conversion of double bonds to epoxides can be obtained after 4 h.
The addition of free acids was not required for the reaction to proceed to conversions exceeding 80%, presumably owing to
generation of FFA by hydrolysis of soybean oil. The enzyme catalyst was found to deteriorate after repeated runs. 相似文献
11.
Asish K. R. Somidi Rajesh V. Sharma Ajay K. Dalai 《Journal of the American Oil Chemists' Society》2015,92(9):1365-1378
The epoxy ring opening and vicinal diacylation of fatty acids in vegetable oils was found to be promising reaction to synthesize stable biolubricants and bioplasticizers. The current research investigation is emphasized on the synthesis of a value added product vicinally diacylated canola oil by sulfated‐ZrO2. The two‐step research approach employed includes: (i) epoxidation, and (ii) epoxy ring opening and vicinal diacylation of epoxidized triglycerides in the canola oil. Sulfated‐ZrO2 was prepared and characterized to measure the physico‐chemical properties required for the effective catalysis. The Taguchi (L16 orthogonal array) statistical design method was employed to optimize the process conditions for the maximum formation of diacylated canola oil. Sulfated‐ZrO2 demonstrated promising activity for the epoxy ring opening and vicinal diacylation of canola oil, and 99 % conversion was achieved at the optimum process conditions of temperature 130 °C, epoxy to acetic anhydride molar ratio (1:1.25), 16 wt% of catalyst loading and reaction time of 1 h which were inferred from the Taguchi analyses. The products were characterized and confirmed with FT‐IR, 1H NMR and sodium spray mass spectroscopy. Spectroscopic analysis also confirmed the absence of intermediate products. The statistical analyses was undertaken to determine the order, rank and interactions among the process variables. The reaction followed Langmuir–Hinshelwood–Hougen–Watson type mechanism and the kinetic data was fitted in overall second order equation. Calculated apparent activation energy was 23.1 kcal/mol. 相似文献
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13.
A. Upendrarao T. Chandrasekhararao R. Subbarao 《European Journal of Lipid Science and Technology》1972,74(6):353-357
Concentrated hydrogen peroxide as well as stronger peracetic acid were prepared by simple methods. Commercial hydrogen peroxide (ca. 30%) was concentrated upto 60% by removing water slowly at low temperature and low pressure. Starting from 60% hydrogen peroxide, strong peracetic acid of 17.2% strength was obtained by a simple operation. Batch epoxidations of vegetable oils such as castor, safflower and linseed oils were carried out for different reaction periods from 2 to 10 hrs and the formation of oxirane oxygen was determined in order to study the effect of epoxidation time, catalyst employed and concentration of hydrogen peroxide as well as of preformed peracetic acid on the extent of epoxidation. The optimum conversions were obtained with 4 hrs reaction period at 50° C by the in situ epoxidation technique using 60% hydrogen peroxide and acid-form of Amberlite-120 resin (chemical grade) as catalyst; the mole ratio of the reactants was unsaturation : hydrogen peroxide : acetic acid (1 : 1.5 : 0.5). 相似文献
14.
Shu-Pei Chang 《Journal of the American Oil Chemists' Society》1979,56(9):855-856
Room temperature transesterification of crambe oil with allyl alcohol gave allyl esters previously prepared by hydrolysis of the oil and reesterification of the mixed acids at elevated temperatures. Treating the esters with m-chloroperbenzoic acid in the presence of sodium bicarbonate resulted in the selective epoxidation of ethylenic bonds and suppression of side reactions. Bifunctional allyl epoxy esters produced in 88% overall yield by this method contain 5.08% oxirane oxygen and an unsaturation equivalent to 91% allyl group; they are prospective monomers for various types of polymerization. 相似文献
15.
二乙醇胺开环环氧大豆油制备大豆多元醇及其性能表征 总被引:1,自引:0,他引:1
以大豆油、冰乙酸和过氧化氢为原料,硫酸为催化剂,合成了不同环氧值的环氧大豆油。再由合成的环氧大豆油与二乙醇胺在四氟硼酸作催化剂的条件下.通过开环加成反应制备了羟基值分别为261mgKOH/g、285mgKOH/g、312mgKOH/g、340mgKOH/g的4种大豆多元醇。用滴定法测定多元醇羟值,用傅立叶变换红外光谱、差示扫描量热法、热重分析法对多元醇进行了分析和表征。结果表明4种多元醇的熔点和热稳定性都随多元醇羟值增大而增大。 相似文献
16.
The synthesis of epoxidized soybean oil acrylate (ESOA) from epoxidized soybean oil (ESO) had been carried out by reacting acrylic acid with the oxirane group in ESO. The acrylated ESO products were characterized using a variety of analytical techniques. The oxygen value, iodine value, and acid value were obtained to know the amount of unsaturation in the synthesized product. Infrared and proton NMR spectra were carried out to confirm the participation of oxirane group in the acrylation reaction. Free‐radical initiators, benzoyl peroxide and tertiary butyl peroxy benzoate, were used for the curing of ESOA resin. Thermal decomposition kinetics of ESOA was studied by the methods of Ozawa, Kissinger, and Horowitz‐Metzger, and the kinetic parameters were compared. The thermal decomposition data of the cured ESOA resin was analyzed by thermogravimetric analysis (TGA) at different heating rates. TG curves showed that the thermal decomposition of the ESOA system occurred in one stage. The apparent activation energies determined by the Ozawa, Kissinger, and Horowitz‐Metzger methods are 122.69, 95.347, and 126.20 kJ/mol, respectively. The results show that there was a reasonably good agreement between the calculated activation energies for stage one in the above methods. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
17.
Rubeena Mungroo Vaibhav V. Goud Satya Narayan Naik Ajay K. Dalai 《European Journal of Lipid Science and Technology》2011,113(6):768-774
Green seed canola oil is underutilized for edible purposes due to its high chlorophyll content, which makes it more susceptible to photo‐oxidation and ultimately reduces the oxidation stability. The present work is an attempt to compare the kinetics of epoxidation of crude green seed canola oil (CGSCO) and treated green seed canola oil (TGSCO) with peroxyacids generated in situ in presence of an Amberlite IR‐120 acidic ion exchange resin (AIER) as catalyst. Among the two oxygen carrier studied, acetic acid was found to be a better carrier than the formic acid, as it gives 8% more conversion of double bond than the formic acid. A detailed process developmental study was then performed with the acetic acid/AIER combination. For the oils under investigation parameters optimized were temperature (55°C), hydrogen peroxide to double bond molar ratio (2.0), acetic acid to double bond molar ratio (0.5), and AIER loading (15%). An iodine conversion of 90.33, 90.20%, and a relative epoxide yield of 90, 88.8% were obtained at the optimum reaction conditions for CGSCO and TGSCO, respectively. The formation of the epoxide product of CGSCO and TGSCO was confirmed by Fourier Transform IR Spectroscopy (FTIR) and NMR (1H NMR) spectral analysis. 相似文献
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20.
Dipak S. Tathe Ramanand N. Jagtap 《Journal of the American Oil Chemists' Society》2013,90(9):1405-1413
Studies on the epoxidation of Prosopis juliflora seed oil were carried out to evaluate the optimum level of oxirane formation. On optimization of epoxidation of Prosopis juliflora oil (PJO), it was observed that at 60 °C and the mole ratio of double bond to the hydrogen peroxide to the acetic acid was 1:1.1:0.5 and at 2 wt% catalyst loading gave the maximum oxirane conversion. Further, epoxidized Prosopis juliflora oil (EPJO) was reacted with aminopropyltrimethoxysilane. Aminopropyltrimethoxysilanated Prosopis juliflora oil (ASPJO) was used as a polyol and was allowed to react with varying concentrations of isophorone diisocyanate resulting in polyurethane. The polyurethane films biodegradability was studied using phosphate buffer and proteinase K. The epoxidized oil was characterized by its epoxy value and FT-IR spectroscopy. Similarly, ASPJO was characterized by its amine value, FT-IR and 1H-NMR spectroscopy. Whereas the polyurethane coating was characterized by gel content, FT-IR spectroscopy, scanning electron microscopic analysis and also evaluated for its chemical resistance, optical and mechanical properties. 相似文献