Some physical properties of castor oil esters and hydrogenated castor oil esters

Esters of castor oil and hydrogenated castor oil were prepared with C₆, C₁₂, C₁₆, C₁₈ fatty acids, using tetra‐n‐butyl titanate as a catalyst and n‐butyl benzene as a water entrainer. Physical properties such as melting point, refractive index, viscosity, and specific gravity of these esters were measured. Slip melting points of the esters were very low in both cases. These esters did not crystallize even at low temperature. The highest slip melting point obtained was 21 °C with stearoyl hydrogenated castor oil ester and lowest slip melting point obtained was —6 °C with hexanoyl castor oil ester.     

蓖麻油的酯交换甲酯化反应

研究了蓖麻油的酯交换甲酯化反应，采用气相色谱法定量检测脂肪酸甲酯的组成，确定了蓖麻油中键合甘油量为9.89%，甲酯混合物中蓖麻醇酸中酯质量分数为88%，工艺优化试验结果为：反应在室温下进行，甲醇用量为理论量的3倍，m（甲醇钠）:m（蓖麻油）=0.4～0.5：100,反应时间为30min-40min。该优化条件下，所得甲酯混合物收率98%以上，蓖麻油全部转化，其中96%转化为甲酯，其余为少量的单甘酯和微量的二甘酯。     

Preparation of rapeseed oil esters of lower aliphatic alcohols

Rapeseed oil esters with lower aliphatic alcohols (C₁−C₄) were prepared in simple batch mode using an alkali (KOH) or acid (H₂SO₄) catalyst. The transesterification reaction conditions were optimized in order to obtain high yields of esters of the quality defined by standards for biodiesel fuels and for a short reaction time. Under these conditions it was possible to prepare only the methyl and ethyl esters catalyzed by KOH. Propyl and butyl esters were obtained only under acid catalysis conditions. The reaction catalyzed by H₂SO₄ was successfully accelerated using slightly higher catalyst concentrations at the boiling points of the alcohols used. The branched-chain alcohols reacted more slowly than their linear homologs, while t-butanol did not react at all. It was also possible to transesterify rapeseed oil using a mixture of alcohols characteristic of the end products of some fermentation processes (e.g., the acetone-butanol fermentation). A simple calculation was made which showed that, because of the higher price of longer-chain alcohols and because of the more intensive energy input during production the esters of these alcohols, they are economically unfavorable as biodiesel fuels when compared with the methyl ester.     

Continuous synthesis of castor oil ethyl esters under supercritical ethanol

The transesterification of castor oil under supercritical ethanol using a catalyst-free continuous process was investigated. The effect of water concentration on the reaction medium, reaction temperature, pressure, and substrates flow rate were studied. A maximum ester content of 74.2% was achieved when the reactor was operated at 573 K, 20 MPa, substrates flow rate of 0.8 ml min⁻¹, and 5 wt% water concentration in the alcohol. The ester content of the product increased with the operation temperature, but after certain temperature level the converse effect was observed. This adverse effect was attributed to oil degradation, which increased to 88.7% at 648 K (at the flow rate of 0.8 ml min⁻¹). A favorable effect on ester content was observed when the water concentration was increased, unlike the effect of water on the conventional alkali-catalyzed process.     

Novel bisphosphonates via castor oil

Hydroxy fatty acids (HFAs) have long been a staple component of feedstock oils with uses ranging from motor oils to food to pharmaceuticals. Castor oil, which contains the HFA ricinoleic acid as its principal component, is the most widely used source of HFA in the world. In addition, bisphosphonates are a functional moiety that has been shown to display a variety of industrial applications, ranging from use in water softeners to osteoporosis drugs, primarily due to their affinity for the calcium ion. We have long been interested in the modification of ricinoleic acid from castor oil to phosphorus derivatives, including α-hydroxy phosphonates and phosphonic acids, and have now accomplished the synthesis of a family of ricinoleic-derived bisphosphonates: one that retains the cis alkene found in ricinoleic acid and one where the alkene has undergone hydrogenation. These compounds have been produced in high yields and high purity and the synthesis of these compounds is reported.     

磺化蓖麻油酸的合成

以浓硫酸磺化蓖麻油酸,得到磺化蓖麻油酸,具有良好的乳化力和渗透力,可作为阴离子表面活性剂,用正交实验优化了磺化反应的工艺条件。结果表明,最佳工艺条件为:n(蓖麻油酸)∶n(浓硫酸)=1∶2,反应温度50℃,反应时间6h。由方差分析和极差分析可知,物料配比n(蓖麻油酸)∶n(浓硫酸)对反应的影响极其显著,其次是反应时间,温度对反应的影响最小。在最优条件下,磺化率可达30%以上,25℃下,粘度>380mPa.s,固含量>80%,产品性能稳定。通过傅立叶红外光谱法、1H NMR、元素分析法、化学分析等鉴定,对合格产品分析可知,得到的磺化蓖麻油酸为高度磺化产品。     

蓖麻油硫酸氢钾催化脱水研究

考察了若干种酸性催化剂对蓖麻油脱水的影响。重点以硫酸氢钾为催化剂,在0.083 MPa真空度下对蓖麻油催化脱水进行了研究。利用正交实验考察了反应温度、反应时间、催化剂用量对脱水反应的影响。得出的最佳工艺条件为:反应温度250℃、反应时间70 m in、催化剂用量1.0%。在该工艺条件下制得的脱水蓖麻油平均碘值可达136,且粘度较小色泽较浅。     

Fatty acid esters with short‐chain alcohols in two‐phase olive pomace oils

Two‐phase decanter olive pomace (TPOP) is the by‐product of a centrifugation system, used to produce olive oil, that separates olive oil and moist pomace. The water content in these olive pomaces is about 70%, while it was 45‐50% in the olive pomace stemming from three‐phase systems (oil, water, and pomace) and 30% in the old press system. The aim of this work is focused on quantification and changes undergone during olive pomace storage in ponds of esters of fatty acids with short‐chain linear alcohols, which can be considered as a refining loss. The results indicate that oil deterioration increases very rapidly, in particular when oil is extracted from the TPOP surface. Special attention should be paid to the storage of TPOP, establishing a maximum of 2 months in all cases.     

Ceramer coatings from castor oil or epoxidized castor oil and tetraethoxysilane

New inorganic-organic hybrids were synthesized through the reaction of castor oil (CO) or epoxidized castor oil (ECO) with tetraethoxysilane (TEOS). The mass proportions of ECO/TEOS varied from 90∶10 to 60∶40, and films of the material were thermally cured. An IR spectroscopy analysis was performed, and macro- and microscopic properties such as adhesion, hardness, swelling in toluene, microstructure (scanning electron microscopy), and T _g were investigated as a function of the proportion of their inorganic-organic precursor. Morphologic studies showed that the hybrid films were homogeneous when lower proportions of the inorganic precursors were used. Hardness and tensile strength increased with TEOS concentration, whereas swelling in toluene decreased with TEOS concentration. Good adhesion was observed throughout the hybrid series.     

Emulsification for castor biomass oil

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance, centrifuge stability, demulsification time in quiescence, appearance of the droplets, and viscosity. The best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan monostearate. Correlation exists between the stability of emulsion and the viscosity/particle size of the droplets, with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water system. Methanol added to the castor oil-water system may decrease the viscosity of the emulsion. Comparing the castor oil-water emulsion with methanol-castor oil-water emulsion, the optimal hydrophilic and lipophilic balance (HLB) value based on castor oil-water system was acquired between 6.6 and 7.5, while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and 6.0. The optimal HLB value of methanol-castor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.     

蓖麻油脂肪酸甲酯乙氧基化物中环氧乙烷分布检测

蓖麻油脂肪酸甲酯乙氧基化物(CA-MEE)用0.5 mol/L KOH乙醇溶液水解,酯键断裂,考察水解次数和水解时间对水解率的影响及回收率;所得亲水基部分之一的甲基聚乙二醇醚用气相色谱法(GC)测其平均环氧乙烷(EO)加合数及其分布,进而考察EO对酯基和仲羟基的选择性。结果表明:CA-MEE在85℃±1℃、1 h条件下能够完全水解,且实验方法有相当好的回收率。样品CA-MEE-12分离出的甲基聚乙二醇醚部分EO加合数色谱图表明,EO对酯基的选择性(EO在酯基上平均加合数为10.0)远高于其对仲羟基的选择性,而且EO分布很窄。     

催化加氢制备氢化蓖麻油的研究

通过正交试验筛选出适合蓖麻油加氢的催化剂及相应的工艺条件。与传统的加氢反应相比，该催化剂的反应条件温和，加氢反应的活性和选择性高。该催化剂是铜镍二元催化剂，采用硅藻土为载体。适宜的铜镍摩尔比为5：l，载体量为40％，催化剂用量为0．8％，在0．8MPa、150℃下反应4h～6h，所得氢化蓖麻油的羟价155．6mg／g，碘价3．05mg／g。催化剂的重复试验和回用试验证明了开发的催化剂具有实际应用价值。粗产品经4％～5％活性炭处理后，色泽(Klette)≤3。     

Physical-chemical properties of waste cooking oil biodiesel and castor oil biodiesel blends

This work presents the physical-chemical properties of fuel blends of waste cooking oil biodiesel or castor oil biodiesel with diesel oil. The properties evaluated were fuel density, kinematic viscosity, cetane index, distillation temperatures, and sulfur content, measured according to standard test methods. The results were analyzed based on present specifications for biodiesel fuel in Brazil, Europe, and USA. Fuel density and viscosity were increased with increasing biodiesel concentration, while fuel sulfur content was reduced. Cetane index is decreased with high biodiesel content in diesel oil. The biodiesel blends distillation temperatures T₁₀ and T₅₀ are higher than those of diesel oil, while the distillation temperature T₉₀ is lower. A brief discussion on the possible effects of fuel property variation with biodiesel concentration on engine performance and exhaust emissions is presented. The maximum biodiesel concentration in diesel oil that meets the required characteristics for internal combustion engine application is evaluated, based on the results obtained.     

Studies on miscibility of dehydrated castor oil epoxy blend with poly(methyl methacrylate)

Oil epoxies can be used as plasticizers in the processing of hard polymers. For this purpose dehydrated castor oil epoxy (DCOE), a product from sustainable resource, has been chosen for blending with poly(methyl methacrylate) (PMMA) to investigate the compatibility of this blend pair. Blends of DCOE/PMMA were prepared in the weight ratios 80/20, 60/40, 40/60, and 20/80 through solution method by mixing in dimethylsulphoxide. Free‐standing films of the blend were cast and the miscibility of the two components was investigated by viscosity and ultrasonic measurements, which provided valuable information on the degree of compatibility of the pairs of blends in solution. The compatibility was also examined by differential scanning calorimetry and scanning electron microscopy. All the studies revealed that DCOE was immiscible with PMMA. However, the appearance and texture of the films were not found to show any visible change over several months, which indicates stability of this blend system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3094–3100, 2006     

蓖麻油聚氨酯-丙烯酸酯复合乳液的合成

采用甲基丙烯酸甲酯（MMA）与蓖麻油水性聚氨酯乳液共聚反应制备聚氨酯丙烯酸酯（PUA）复合乳液,研究了蓖麻油水性聚氨酯性能、MMA添加量、引发剂种类和聚合温度对PUA复合乳液及涂膜性能的影响,并应用傅里叶红外光谱（FTIR）测定反应产物的结构.研究发现,用外观半透明或微透明的PU-M分散液制备的PUA乳液及涂膜性能优良.油溶性引发剂（AIBN）比水溶性引发剂（K₂S₂O₈）更适合本体系的乳液聚合.随着MMA含量增大,PUA复合乳液胶粒粒径增大,黏度减小,涂膜光泽度下降,机械性能变好,耐水性增加.合适的MMA含量为体系总固含量的20%～30%.提出了PUA复合乳液胶粒形成及粒径长大机理.     

蓖麻油磷酸催化脱水研究

以H3PO4为催化剂,在减压下对蓖麻油催化脱水进行了研究。利用正交实验考察了反应温度、反应时间、催化剂用量、真空度对脱水反应的影响。得出的最佳工艺条件为:反应温度250℃、反应时间90min、催化剂用量1.0%、真空度600×133.3Pa。在该工艺条件下制得的脱水蓖麻油平均碘值达到138,且色泽较浅。     

Production of hydrocarbons by pyrolysis of methyl esters from rapeseed oil

The pyrolysis of a mixture of methyl esters from rapeseed oil has been studied in a tubular reactor between 550 and 850°C and in dilution with nitrogen. A specific device for the condensation of cracking effluents was used for the fractionated recovery of liquid and gaseous effluents, which were analyzed on-line by an infrared analyzer and by gas chromatography. The cracking products in the liquid effluent were identified by gas chromatography/mass spectrometry coupling. The effects of temperature on the cracking reaction were studied for a constant residence time of 320 ms and a constant dilution rate of 13 moles of nitrogen/mole of feedstock. The principal products observed were linear 1-olefins,n-paraffins, and unsaturated methyl esters. The gas fraction also contained CO, CO₂, and H₂. The middle-chain olefins (C₁₀–C₁₄ cut) and short-chain unsaturated esters, produced with a high added value, had an optimum yield at a cracking temperature of 700°C.     

蓖麻油聚氨酯IPN黄变性能的研究

分别用2,4-甲苯二异氰酸酯(TDI)和六亚甲基二异氰酸酯(HDI)与蓖麻油反应制备出两种多异氰酸酯预聚体,再与交联剂(环氧树脂或烯类单体)反应制备出了不同的蓖麻油聚氨酯互穿网络型聚合物(IPN),通过黄色指数的测定,研究了体系组成对IPN黄变性能的影响。     

蓖麻油型单组分聚氨酯发泡胶的制备

研究了以蓖麻油、聚醚多元醇、聚酯多元醇、PAPI为原料合成系列发泡单组分聚氯酯胶粘剂的工艺,研究了各因素对预聚体的合成、产品性能及贮存稳定性的影响。结果表明,异氰酸酯指数为28～30,蓖麻油为多元醇总质量的40％,预聚催化剂为T-12,固化催化剂为吗啉类和LX-1,溶剂为乙酸乙酯和二氧甲烷,在70-80℃下反应3h,得到符合建材工业要求的产品。     

Fractionation of squid visceral oil ethyl esters by short-path distillation

Squid visceral oil contains high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Its ethyl esters were fractionated by short-path distillation in this study. The elimination temperatures of squid visceral oil ethyl esters (SVOEE) ranged from 50 to 140°C, increasing with the carbon number of ethyl esters. The elimination temperature of cholesterol was higher than those of SVOEE. The SVOEE of Illex argentinus (SVOEE-A) was more advantageous as the raw material (feed) than that of Ommastrephes bartrami (SVOEE-B) for the isolation of EPA and DHA, because SVOEE-A contained less 20∶1 and 22∶1. When SVOEE-A originally containing 9.0% EPA, 14.7% DHA, and 1,121 mg/100 g of cholesterol was distilled from 50 to 150°C with 20°C interval, the 130°C distillate could give 15.5% EPA and 34.7% DHA with 99 mg/100 g of cholesterol, and the yield was 21.8%. The 150°C distillate could give 43.1% DHA with 496 mg/100 g of cholesterol. Furthermore, the distillates collected from 110 to 150°C contained 24.4 to 50.2% of EPA plus DHA, and their total yield was 58.3%. The final residue after 150°C distillation contained 77% of the total cholesterol in the initial SVOEE-A, and the yield was 6.0%.