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1.
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
2.
Summary Variations in quantity and concentration of hydrogen peroxide were studied in epoxidation of soybean oil by using the partially
preformed peracetic acid epoxidation method.
Use of a hydrogen peroxide/olefin mole ratio as low as 1.05/1 yields epoxidized soybean oil that meets the low iodine number
and high epoxide content characteristics required for stabilizer-plasticizer use.
Use of a hydrogen peroxide/olefin mole ratio as low as 0.50/1 results in more than 95% hydrogen peroxide utilization and yields
epoxidized soybean oil containing more than two epoxide groups per molecule. Products of this type may be of interest for
recently proposed applications in alkyd, polyester, and epoxy resins.
Increasing the hydrogen peroxide concentration to 70% in epoxidation permits reduction of acetic acid usage to half that required
when 50% hydrogen peroxide is used. Agitation control is also necessary for optimum results. A two-step epoxidation method
can be used to avoid formation of potentially detonable mixtures in epoxidation with 70% hydrogen peroxide by the partially
preformed peracetic acid method.
Presented at the 32nd annual meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958. 相似文献
3.
Vaibhav V. Goud Anand V. Patwardhan Srikanta Dinda Narayan C. Pradhan 《European Journal of Lipid Science and Technology》2007,109(6):575-584
Karanja oil with an iodine value of 89 g/100 g was epoxidised in situ with aqueous hydrogen peroxide and acetic acid in the presence of Amberlite IR‐120 acidic ion exchange resin as catalyst. The effect of the operating variables on the oxirane oxygen content, as well as on the oxirane ring stability and the iodine value of the epoxidised karanja oil, were determined. The variables studied were stirring speed, hydrogen peroxide‐to‐ethylenic unsaturation molar ratio, acetic acid‐to‐ethylenic unsaturation molar ratio, temperature, and catalyst loading. The effects of these parameters on the conversion to the epoxidised oil were studied and the optimum conditions for the maximum oxirane content were established. The proposed kinetic model takes into consideration the two side reactions, namely, epoxy ring opening involving the formation of hydroxy acetate and hydroxyl groups, and the reaction between the peroxyacid and the epoxy group. The kinetic and adsorption constants of the rate equations were estimated by the best fit using Marquardt's algorithm. Good agreement between experimental and predicted data validates the proposed kinetic model. From the estimated kinetic constants, the apparent activation energy for the epoxidation reaction was found to be 11 kcal/mol. 相似文献
4.
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
5.
B. Dahlke S. Hellbardt M. Paetow W. H. Zech 《Journal of the American Oil Chemists' Society》1995,72(3):349-353
A novel process for the industrial production of hydroxylated fatty acids involves epoxidation of plant oils and their derivatives,
followed by catalytic epoxy ring opening in the presence of water or other hydrogen donors, such as alcohols, diols, and amines.
Depending on the starting material, epoxidation followed by opening of the oxirane ring leads to fatty acids that contain
vicinal diol groups or to other substituted hydroxylated fatty acid derivatives. As an example for the preparation of a substituted
hydroxylated fatty acid derivative, the reaction of epoxidized rapeseed oil with monobutylamine as hydrogen donor is described.
Apart from the intended formation of hydroxyl groups with vicinal aminoalkyl groups, partial aminolysis of the ester compound
was also observed. Another example describes the reaction of epoxidized rapeseed oil with different molar proportions of 1,4-butanediol
as hydrogen donor. Depending on the molar proportion of the hydrogen donor, interesterification, or intermolecular ether formation
were observed as side reactions. The properties of various technical hydroxylated fatty acids and their derivatives, prepared
according to this novel process, are given, and potential applications of these products are suggested. 相似文献
6.
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
7.
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
8.
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
9.
菜籽油环氧化制备润滑油基础油的研究 总被引:1,自引:0,他引:1
植物油基润滑油具有良好的润滑性能和可生物降解的优点,是可持续生产的绿色润滑油.今以菜籽油为原料、双氧水和乙酸为氧化剂,采用固体酸--CD-450强酸性阳离子交换树脂为催化荆,对菜籽油进行环氧化,从而制取环氧化菜籽油,即菜籽油润滑油.研究了固体酸的催化性能,实验考察了反应温度、反应时问、催化剂用量等因索对菜籽油环氧化反应的影响规律,并分别通过红外光谱和盐酸-丙酮法对菜籽油环氧化产物进行定性和定量分析,证明了目标产物的存在,定量确定了环氧化产物的环氧值.实验对CD-450强酸性阳离子交换树脂和浓硫酸的催化性能进行了比较,同时也考察了阳离子树脂的再生利用性能.研究结果表明强酸性阳离子交换树脂可以用作催化剂进行菜籽油环氧化生产润滑油基础油,该制各方法因无强矿物酸排放、是环境友好型的绿色生产工艺,具有实际应用价值. 相似文献
10.
Kenneth D. Carlson Robert Kleiman Marvin O. Bagby 《Journal of the American Oil Chemists' Society》1994,71(2):175-182
Lesquerella gordonii (Gray) Wats andLimnanthes alba Benth. (Meadowfoam) are species being studied as new and alternative crops. Triglyceride oil from lesquerella contains 55–60%
of the uncommon 14-hydroxy-cis-11-eicosenoic acid. Meadowfoam oil has 95% uncommon acids, includingca. 60%cis-5-eicosenoic acid. Both oils are predominantly unsaturated (3% saturated acids), and have similar iodine values (90–91),
from which oxirane values of 5.7% are possible for the fully epoxidized oils. Each oil was epoxidized withm-chloro-peroxybenzoic acid, and oxirane values were 5.0% (lesquerella) and 5.2% (meadowfoam). The epoxy acid composition of
each product was examined by gas chromatography of the methyl esters, which showed that epoxidizedL. gordonii oil contained 55% 11,12-epoxy-14-hydroxyeicosanoic acid, and epoxidized meadowfoam oil contained 63% 5,6-epoxyeicosanoic
acid, as expected for normal complete epoxidation. Mass spectrometry of trimethylsilyloxy derivatives of polyols, prepared
from the epoxidized esters, confirmed the identity of the epoxidation products and the straightforward nature of the epoxidation
process. Synthesis and characterization of these interesting epoxy oils and derivatives are discussed. 相似文献
11.
Shangde Sun Guolong Yang Yanlan Bi Hui Liang 《Journal of the American Oil Chemists' Society》2011,88(10):1567-1571
Epoxidized vegetable oils can be used as renewable biodegradable and non-toxic lubricants, polymer stabilizers, and as intermediates.
In this study, as a renewable resource, corn oil rich in oleic and linoleic acids, which was epoxidized using hydrogen peroxide
as an oxygen donor and stearic acid as an active oxygen carrier in the presence of Novozym 435. The process was optimized
for the enzymatic epoxidation of corn oil with an epoxy oxygen group content of 5.8 ± 0.2% and a percentage relative conversion
to oxirane of 85.3 ± 2.9% under the following conditions: 35 °C, 28% stearic acid load (relative to the weight of corn oil),
2.7:1 mol ratio of H2O2/C=C-bonds, and 10 h. The influence on the enzymatic epoxidation decreased in the order of stearic acid load > reaction temperature ≈ mole
ratio of H2O2/C=C-bonds >reaction time. 相似文献
12.
In the presence of an immobilized lipase fromCandida antacrtica (Novozym 435R) fatty acids are converted to peroxy acids by the reaction with hydrogen peroxide. In a similar reaction, fatty acid esters
are perhydrolyzed to peroxy acids. Unsaturated fatty acid esters subsequently epoxidize themselves, and in this way epoxidized
plant oils can be prepared with good yields (rapeseed oil 91%, sunflower oil 88%, linseed oil 80%). The hydrolysis of the
plant oil to mono- and diglycerides can be suppressed by the addition of a small amount of free fatty acids. Rapeseed oil
methyl ester can also be epoxidized; the conversion of C=C-bonds is 95%, and the composition of the epoxy fatty acid methyl
esters corresponds to the composition of the unsaturated methyl esters in the substrate.
Based partly on a lecture at the 86th AOCS Annual Meeting & Expo, San Antonio, Texas, May 7–11, 1995. 相似文献
13.
Kyu-Wan Lee Cheng Hailan Jin Yinhua Young-Wun Kim Keun-Woo Chung 《Korean Journal of Chemical Engineering》2008,25(3):474-482
Vegetable oils are a major source of many base chemicals. Unfortunately, most vegetable oils exhibit lower thermal and oxidation
stability because of double bonds and even worse low-temperature behaviors. These physical and chemical properties can be
improved by various chemical modifications. The catalytic hydrogenation of soybean oil (SBO) over 25% Ni/SiO2 and 5% Pt/C is one of them, and the epoxidation of soybean oil and reduced soybean oil (RSBO) was carried out by using 30%
of hydrogen peroxide and acetic acid in the presence of conc. sulfuric acid, and/or acidic Amberlyst 15 resin catalyst. Various
alcohols and amines were added to the epoxidized soybean oil (ESBO) in the hope of improving lubricant properties. The reaction
products were carefully analyzed by means of 1H-NMR, FT-IR spectroscopies and GC-MS spectrometry. This paper covers the epoxidation of virgin and RSBOs, alcoholysis and
amidation of ESBO and SBO. Finally, the structures of cross linked products synthesized from ESBO and SBO with 1,6-hexamethylendiamine
were proposed. 相似文献
14.
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
15.
R. Raghavachar R. J. Letasi P. V. Kola Z. Chen J. L. Massingill 《Journal of the American Oil Chemists' Society》1999,76(4):511-516
Epoxidized crambe oil and rapeseed oil were synthesized by reaction of the oils with m-chloroperoxybenzoic acid. Formulating the neat epoxidized oils with epoxy-amine systems gave two-phase thermosets with epoxidized
crambe oil, but not with epoxidized rapeseed oil. Glass transition temperature, mechanical properties, and fracture toughness
of the epoxidized crambe oil thermoset specimen were measured. Fracture toughness values of the epoxy thermosets were increased
approximately 100% by both 5 and 10% epoxidized crambe oil. Glass transition temperature and mechanical properties were affected
only modestly. 相似文献
16.
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
17.
18.
Wilkinson's catalyst [RhCl(PPh3)3] has been used to conjugate fish oils in high yields under very mild reaction conditions. A catalyst load of 0.35 mol% of
RhCl(PPh3)3, 0.43 mol% of (o-CH3C6H4)3P, and 0.87 mol% of SnCl2·2H2O in ethanol solvent at 60°C for 2 d produces 82% conjugated Norway fish oil affords 90% conjugated fish oil in 93% yield.
The Sharpless epoxidation procedure has also been employed to epoxidize fish oils. Using 0.34 mol% of CH3ReO3, 8.15 mol% of pyridine, and 1.03 equivalents of aq. 30% hydrogen peroxide in methylene chloride solvent at 25°C for 6 h,
the Norway fish oil ethyl ester can be 100% epoxidized in an 86% yield. The Capelin fish oil gives 100% epoxidized fish oil
in a 72% yield. Decreasing the amounts of CH3ReO3 and pyridine used in the reaction results in partially epoxidized fish oils. 相似文献
19.
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