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1.
杨薇 《广州化工》1997,25(3):12-14
本文阐述无味环氧豆油的合成技术,将精制大豆油,乙酸与其它辅料按配方比例投入反应釜,再慢慢滴加双氧水,使之环氧化反应,待反应完全后,经水洗,中和,脱水等一系列工艺,制成无味环氧豆油成品。这种合成方法,工艺简单,产品质量稳定优良。  相似文献   

2.
New materials derived from metathesized soybean oil have been prepared and characterized. Thermal polymerization of metathesized soybean oil in the presence of air results in yellow, brittle gels. These materials display a curious tendency to produce audible popping sounds when exposed to chlorinated organic solvents, such as chloroform or dichloromethane. Complete hydrogenation of metathesized soybean oil has been accomplished in excellent yields utilizing 10% palladium on carbon in dichloromethane. A new, very mild, effective epoxidation procedure for soybean oil, utilizing methyltrioxorhenium (VII) (MTO) and pyridine as the catalyst system and hydrogen peroxide as the oxidant, has been developed. This epoxidation reaction affords excellent yields of epoxidized soybean oil with some control of the degree of epoxidation at very low MTO concentrations (< 0.5 mol%). This reaction is also very effective for the epoxidation of metathesized soybean oil to higher molecular weight epoxidized soybean oil materials.  相似文献   

3.
In the present work, the kinetics of the epoxidation of soybean oil (SBO) by peroxyacetic acid (PAA) generated in situ in the presence of sulfuric acid as the catalyst was studied at various temperatures (45, 65 and 75 °C). It was found that epoxidation with almost complete conversion of unsaturated carbon and negligible oxirane cleavage can be attained by the in situ technique. The rate constant for epoxidation of SBO was found to be of the order of 10–6 mol–1s–1 and the activation energy of epoxidation is 43.11 kJ/mol. Some thermodynamic parameters: enthalpy, entropy and free activation energy of 40.63 kJ/mol, –208.80 J/mol and 102.88 kJ/mol, respectively, were obtained for the epoxidation of SBO. The kinetic and thermodynamic parameters of epoxidation obtained from this study indicate that an increase in the process temperature would increase the rate of epoxide formation. The epoxidation of corn oil and sunflower oil were also investigated under the same conditions. The results show that the reaction rate is in the order of soybean oil > corn oil > sunflower oil.  相似文献   

4.
PVC增塑剂环氧大豆油生产新技术研究   总被引:1,自引:0,他引:1  
文章以大豆油为原料,采用无溶剂法生产工艺,在大孔强酸性树脂催化剂作用下,制备出PVC环保型增塑剂环氧化大豆油。试验中对过氧化剂种类、反应催化剂及操作条件进行了系统考察;制备出的环氧化大豆油具有环氧值高,酸值和碘值低的特点,是性能优异PVC环保型增塑剂。采用先过氧化再环氧化的分步合成工艺,可使环氧化时间大大缩短,降低了副反应程度,提高了生产效率和产品质量。  相似文献   

5.
Characterization of Soybean Oil/Epoxidised Soybean Oil Mixtures by FTIR/h-ATR-Spectroscopy Controlling of technical production process requires a rapid method of analysis. This article describes a Fourier transform-infrared/horizontal attentuated total reflectance (FTIR/h-ATR) method to determine the iodine value and the degree of epoxidation in binary mixtures of soybean oil and epoxidised soybean oil. This analytical method will also be tested regarding the chemical reaction of epoxidation of soybean oil.  相似文献   

6.
The world production of epoxidized vegetable oil, mainly epoxidized soybean oil, is continuously increasing because this product can have a wide range of applications. Non‐edible vegetable oils, recovered by the plants growing on marginal and polluted lands, represent a possible answer to industry versus food chain debate. Cardoon (Cynara cardunculus L.) seed oil can be considered as an interesting and sustainable alternative to edible soybean oil to make plasticizers. In this work, a comparison between different epoxidation methods of cardoon oil is depicted and argued, focusing on strong points and weaknesses for each of them. It is found that cardoon seed oil can be successfully epoxidized through feasible existing technologies, by peracids and hydrogen peroxide equally. Moreover, it is demonstrated that a “greener” cardoon oil epoxidation process is possible, by using hydrogen peroxide in the presence of commercial γ‐alumina as heterogeneous solid catalyst. Practical Applications: The paper analyzes the advantages and the problems of different epoxidation methods in order to obtain a final product with high quality and answer the environmental, social, and economic sustainability requirements.  相似文献   

7.
In this article, we investigate the role of triacylglycerol composition on the properties of epoxidized vegetable oils and the kinetics of the epoxidation process under conditions comparable to commercial epoxidation. Commodity soybean oil (24% oleic acid, 50% linoleic acid, and 7% linolenic acid), high‐oleic soybean oil (75% oleic acid, 8% linoleic acid, and 2.5% linolenic acid), and linseed oil (11% oleic acid, 15% linoleic acid, and 64% linolenic acid) were each epoxidized to various extents. Epoxidation rate, viscosity, differential calorimetry, and X‐ray diffraction data are presented for these oils and interpreted in the context of their fatty acid profile (mostly oleic, linoleic, or linolenic). While fully epoxidized soybean oil is widely commercially available and used in an increasing array of industrial applications, information relating to partially epoxidized oils and epoxidized oils of other cultivars is less well known.  相似文献   

8.
随着石油储备需求的增加,油罐规模正向大型化以及能适应极限工况的方向发展。准确掌握罐内油品温度场的变化规律,对于保障油库安全经济运行具有重要意义。针对太阳辐射、大气温度等储罐环境的周期性变化条件,运用传热学相关理论,建立了大型双盘浮顶储罐非稳态传热过程的理论模型,通过对模型区域进行离散化得到边界节点的向前差分方程,在确定罐内原油物性参数、储罐传热系数以及边界热通量的基础上,研究得出储罐原油温度场的数值模拟方法。对大庆某10×104 m3浮顶储罐的应用分析表明,罐顶温降速率随着太阳辐射强度以及大气温度的降低而增大;罐壁温降速率受太阳辐射影响较小,随大气温度的降低而增大;罐底近似于绝热,温降速率受外界环境影响较小,研究结果可为优化大型浮顶罐的储存工艺设计及生产管理提供一定的理论支持。  相似文献   

9.
文章采用732#强酸性阳离子交换树脂为催化剂,改进型无溶剂法合成高品质环氧大豆油。实验确定了高品质环氧大豆油的最佳合成条件:采用逐步加料,按m(大豆油):m(88%甲酸):m(30%双氧水):m(催化剂)=1:0.35:1.2:0.15的比例加料,加0.5 mL 1%的EDTA稳定剂,制得的环氧大豆油品质较高。  相似文献   

10.
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   

11.
A series of epoxidized‐soybean oil (ESO) with different epoxyl content were synthesized by in situ epoxidation of soybean oil (SBO). The acrylated epoxidized‐soybean oil (AESO) was obtained by the reaction of ring opening of ESO using acrylic acid as ring opener. The acrylated expoxidized‐soybean oil‐based thermosets have been synthesized by bulk radical polymerization of these AESOs and styrene. The thermal properties of the resins were characterized by differential scanning calorimetry (DSC) and thermo‐gravimetric analysis (TG). The results showed that these resins possess high thermal stability. There were two glass transition temperature of each resin due to the triglycerides structure of the resins. The tensile strength and impact strength of the resins were also recorded, and the tensile strength and impact strength increased as the iodine value of ESO decreased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

12.
We studied the methyltrioxorhenium (MTO)-CH2Cl2/H2O2 biphasic system for epoxidizing soybean oil. The reactions were optimized (reactant ratio, time, and temperature), which resulted in a better performance (higher conversion and selectivity) than those described in the literature. Total doublebond conversion and 95% selectivity were obtained in 2 h at room temperature. Furthermore, it was possible to reach desired epoxidation degrees by changing the oxidant and MTO amounts. The rhenium-epoxidized soybean oil remained stable in the absence of stabilizers for up to 30 d when stored at mild conditions.  相似文献   

13.
The soy polyols were prepared from epoxidation of soybean oil followed by ring opening of oxirane obtained by using methanol as the ring opener. Polyols of hydroxyl (OH) numbers ranging from 128 to 174 mg of KOH/g were obtained by the variation of epoxidation time of soybean oil. A novel cast polyurethane resin has been synthesized by these polyols and 2,4‐toluene diisocyanate. Swelling of networks in toluene showed that the sol fraction varies from 1.13 to 72.06%. The thermal and mechanical properties of cast resins were characterized by differential scanning calorimetry and thermogravimetric analysis. The results showed that the glass transition temperature increases with the increase of OH number and that the thermal stability of the resins was slightly decreased with the increasing OH number. The tensile strength at break increases with the increase of OH number. Polyols with OH number of 174 mg of KOH/g gave glassy polymers, whereas those below this value gave rubbers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

14.
王敏  邵倩倩  杨晓帆  李敬法 《化工学报》2020,71(5):2035-2048
利用盘管组来加热融化浮顶油罐内含蜡原油是油罐加热融化的主要方式之一。而优化盘管组的布置方式对提高罐内含蜡原油的融化效率、降低生产成本具有重要的意义。基于此,在考虑含蜡原油融化过程中形态和流变性变化的基础上,建立了盘管组加热的浮顶油罐内含蜡原油湍流融化物理数学模型。考虑到罐顶空气层、钢板层、保温层的规则性以及罐内含蜡原油区域的非规则性,利用浸入边界法在结构化网格上处理罐内含蜡原油与盘管组之间的耦合问题。利用文献结果对模型进行验证。以实际1000 m3浮顶油罐为例,对罐内含蜡原油的融化规律进行研究,并对倾角对融化过程的影响进行分析。  相似文献   

15.
Mechanical and thermal properties of materials prepared by curing epoxidized soybean oil with various cyclic acid anhydrides in the presence of tertiary amines were investigated by dynamic mechanical thermal analysis and thermogravimetry. All samples presented thermoset material characteristics that were dependent upon the type of anhydride, the anhydride/epoxy molar ratio, and epoxy group content. The thermosets obtained from anhydrides with rigid structures as such phthalic, maleic, and hexahydrophthalic showed higher glass transition temperatures (Tg) and cross-linking densities. As expected, the Tg decreased as the anhydride/epoxy ratio decreased. The influence of the degree of epoxidation of soybean oil on the mechanical properties and Tg was also investigated. It was found that the higher the epoxy group amount, the higher the Tg and hardness. Cured resins exhibited thermal stability up to 300°C, except for those prepared with dodecenyl succinic anhydride, which began to decompose at lower temperature. They presented excellent chemical resistance when immersed in 1% wt/vol NaOH and 3% wt/vol H2SO4 solutions but poor chemical resistance in the presence of organic solvents.  相似文献   

16.
大型浮顶油罐温度场数值模拟   总被引:1,自引:0,他引:1       下载免费PDF全文
大型浮顶油罐温度场的准确预测对于原油的战略和商业储备均有着重要的意义。油罐中温度场受大气温度、罐壁保温层厚度与热导率、太阳辐射强度、罐底土壤物性、油品物性等因素的影响。本文考虑以上众多因素的影响,建立了二维大型浮顶油罐温度场预测模型,开发了将浮舱区、油品区、土壤区及罐壁和保温层耦合求解的SIMPLE算法程序。研究了太阳辐射、保温层厚度等因素对油品温度的影响,并将计算结果与现场测试数据进行了对比,发现本模型的预测结果与实验结果吻合良好。  相似文献   

17.
Microporous polyethylene (PE) membranes having a controlled pore size were produced via the thermally induced phase separation process by manipulation of the phase boundary of the PE/diluent blend and process conditions. The phase boundary of the PE blend, caused by upper critical solution temperature type phase behavior, was controlled by the use of a diluent mixture, that is, an isoparaffin/soybean oil mixture. The phase-separation temperature of the PE/soybean oil blend was always higher than that of the PE/isoparaffin blend. In PE/(isoparaffin/soybean oil) ternary blends, the phase-separation temperature of the ternary blend rapidly increased with increasing soybean oil content in the diluent mixture. Furthermore, the phase-separation temperatures of ternary blends were always higher than that of the PE/soybean oil blend, regardless of the blend compositions, when the diluent mixture contained more than 50 wt % soybean oil. The observed phase behavior of the ternary blends was analyzed with interaction energy densities calculated with the Flory–Huggins theory and ternary stability conditions. The growth of droplets caused by both coalescence and the Oswald ripening process was observed after the onset of phase separation. As the blends became less stable, the droplet growth rate increased, and larger equilibrium droplets were formed. Microporous membranes with the desired pore structure could be prepared by control of the phase boundary and the variation of processing conditions such as the quenching depth, annealing time, and cooling rate. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

18.
李玉  徐春明  韩帅  李鸿烨 《化工学报》2020,71(7):3372-3378
拱顶油罐受外部火焰烘烤发生失效爆炸,易造成严重人员伤亡和巨大经济损失。为对火灾条件下拱顶油罐的失效爆炸进行预警,通过高温材料力学性能实验平台对拱顶油罐弱连接结构进行破坏测试,得出不同火灾温度条件下弱连接结构失效的拉断力和应力值。实验结果表明,当温度高于300℃时,拉断力和失效应力值变化显著,其中450℃为变化峰值温度。在此基础上,构建了拱顶油罐失效压力计算模型,推导出了不同容积拱顶油罐在不同火灾温度下的失效压力。所得结果可作为拱顶油罐失效的判定依据,为油罐的爆炸预警提供数据支撑。  相似文献   

19.
环氧鱼油的性质及其应用研究   总被引:2,自引:0,他引:2  
采用一步环氧化工艺制得环氧值为4.5%的环氧鱼油,研究环氧鱼油的性质及其在氯乙烯中的作用。研究结果表明:环氧鱼油耐热性高,用于聚氯乙烯中,与金属皂并用有良好的协同稳定作用,作用效果与环氧大豆油相当甚至更好些,可作为聚氯乙烯优良的增塑剂兼稳定剂。  相似文献   

20.
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   

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