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1.
The development and optimisation of the synthesis of an analogue of jojoba oil has been carried out. The product is an ester with characteristics similar to those of sperm whale oil and jojoba oil. This permits its use as a substitute for these two natural oils. A central composite design has been used in the synthesis of this fine chemical. The variables selected for the present study are reaction temperature, initial concentration of catalyst and working pressure. Temperature is the most significant factor in the esterification process, and its influence is positive. Pressure has a negative influence, and the concentration of catalyst a positive influence, on the process. Depending on the temperature value, the influence of the interactions can be more important than that of the other two main effects, pressure and catalyst concentration. Response surface models have been found adequately to represent the yield of ester. The commercial quality of the synthesised product is very similar to that of natural jojoba oil. Because of its low cost, this synthesis process is considered, from an economical point of view, very attractive. 相似文献
2.
Synthesis of oleyl oleate as a jojoba oil analog 总被引:2,自引:0,他引:2
N. Sánchez M. Martinez J. Aracil A. Corma 《Journal of the American Oil Chemists' Society》1992,69(11):1150-1153
Synthesis of a wax ester analog of jojoba oil was accomplished from oleic acid and oleyl alcohol with a zeolite as catalyst.
A full 23 factorial design at two levels has been used in the synthesis. The variables selected were temperature, reduced pressure
and initial catalyst concentration. The most important variable within the range studied was temperature. Reduced pressure
had a negative influence, and initial catalyst concentration showed a positive influence on the process. A response equation
has been determined for the yield of ester. The properties of the synthesized product are similar to those of natural jojoba
oil. 相似文献
3.
E. W. Bell L. E. Gast F. L. Thomas R. E. Koos 《Journal of the American Oil Chemists' Society》1977,54(6):259-263
Synthetic wax esters with properties similar to those of sperm whale oil have been prepared entirely from soybean and linseed
oils. the synthesis required: (a) selective hydrogenation of the oils with copper-on-silica gel catalyst, (b) hydrogenolysis
of fatty acids to fatty alcohols with copper-cadmiumchromium catalyst, and (c) esterification of hydrogenolysis products to
yield predominantly long chain fatty esters which contained unsaturation in both the alcohol and acid moieties. Similarity
of physical and chemical properties indicate that these wax esters are possible replacements for sperm oil. After sulfurization,
the wax esters also have potential as extreme pressure lubricant additives. 相似文献
4.
D. H. Buisson D. R. Body G. J. Dougherty L. Eyres P. Vlieg 《Journal of the American Oil Chemists' Society》1982,59(9):390-395
The lipid fraction of the deep water fish species orange roughy (Hoplostetbus atlanticus), black oreo (Allocyttus sp.) and small spined oreo (Pseudocyttus maculatus) had wax esters with even carbon numbers over the range C30 to C46 as the major components. The component acids and alcohols of the wax ester fraction were analyzed by gas liquid chromatography
and compared with those of jojoba and sperm whale oils. Orange roughy oil was refined and deodorized and its chemical, physical
and mechanical properties were determined. Hydrogenation of orange roughy oil produced a range of white crystalline waxes
with melting points between 34 and 66 C. The characteristics of these waxes were very similar to those of hydrogenated jojoba
oil and spermaceti. Lubricant tests performed on sulfurized orange roughy oil indicated it is comparable to sulfurized jojoba
and sperm whale oils as an extreme-pressure additive in lubricants. The results show a sound technical basis on which to consider
an industry based on orange roughy oil and the oreo oils as replacements for sperm whale oil and as substitutes for jojoba
oil. Applications for the oil could be in the cosmetic and high-grade lubricant fields, the waxes in the polish, textile,
cosmetic and pharmaceutical industries and the sulfurized derivative of orange roughy oil in the lubricant industry. 相似文献
5.
6.
Karla T. Kucek Maria Aparecida F. César-Oliveira Helena M. Wilhelm Luiz P. Ramos 《Journal of the American Oil Chemists' Society》2007,84(4):385-392
The ethanolysis of refined soybean oil was investigated through a 23 experimental design that was carried out under the following levels: ethanol:oil molar ratios (MR) of 6:1 and 12:1, NaOH concentrations of 0.3 and 1.0 wt% in relation to the oil mass, and reaction temperatures of 30 and 70 °C. The ethanol:oil MR and the alkali concentration had an almost equivalent influence on the reaction yield, whereas the influence of increased reaction temperatures was very limited and higher catalyst concentrations led to greater yield losses due to the formation of soap. Ethyl ester yields of 97.2% were obtained at 70 °C, MR of 12:1 and 0.3 wt% NaOH. Replacement of 0.3 wt% NaOH by 1.0 wt% KOH under the same reaction conditions led to lower ester yields. Likewise the former, KOH provided the maximum ester yield (95.6%) at the highest molar ratio (12:1), with the reaction temperature having little influence on the catalyst performance. Ester yields beyond 98% were only achieved when a second ethanolysis stage was included in the process. In this regard, the application of 2 wt% Magnesol® after the first ethanolysis stage eliminated the need for water washing prior to the second ethanolysis stage and helped to generate a final product with less contaminating unreacted glycerides. 相似文献
7.
硬脂酰单宁酸酯的合成及抗氧化作用 总被引:4,自引:0,他引:4
以单宁酸和硬脂酰氯为原料合成了一种油溶性抗氧化剂硬脂酰单宁酸酯 (C18 TA)。探讨了硬脂酰氯和单宁酸的量比、催化剂对甲苯磺酸的用量、反应温度和溶剂等对合成的影响。确定了较佳的反应条件 :n(单宁酸 )∶n(硬脂酰氯 ) =1∶2 0 ,m(单宁酸 )∶m(催化剂 ) =1 0 0 :0 .0 3 ,二氧六环作溶剂 ,反应温度 10 0~ 10 2℃ ,氮气保护下反应 4h。C18 TA在菜籽色拉油中的含量为6 0 0mg/kg时 ,6 0℃强制氧化 18d ,其POV抑制率可达 6 6 0 % ,明显高于相同条件下BHT的POV抑制率 5 6 0 % 相似文献
8.
9.
K. Guruz W.L. Kranich A.H. Weiss C. Dyke P. Rambelli A. Foutsitzis 《Fuel Processing Technology》1982,6(2):183-201
Finely ground North Dakota lignite slurried in anthracene oil was hydrogenated in a continuous stirred tank reactor in the presence of a cobalt-molybdenum catalyst. Effects on product distribution of process variables such as H2 pressure, temperature, space time, lignite concentration in anthracene oil, and catalyst concentration have been investigated. Results indicate that 80% of maf lignite can be converted into gaseous and liquid products with an oil yield of about 35% on the same basis. 相似文献
10.
《Diamond and Related Materials》2004,13(9):1638-1644
The synthesis of graphite at higher pressure and temperature conditions in the presence of a catalyst–solvent metallic alloy is a commonly applied process for industrial diamond production. The product obtained after this synthesis is an agglomerate composed by diamonds crystals, metallic particles, non-transformed graphite and other compounds. The diamond extraction from the agglomerates is known as purification. In this work the diamond purification process by alkaline melt was studied by statistical methods. It was shown that the alkaline melt could be a very efficient process and environmentally correct procedure for diamond purification. 相似文献
11.
无溶剂法合成蔗糖硬脂酸酯的工艺研究 总被引:7,自引:0,他引:7
以乙醇代替有毒的甲醇与硬脂酸在酸催化下进行反应制出了硬脂酸乙酯。以硬脂酸乙酯与蔗糖为原料在催化剂和乳化剂的作用下,进行酯交换反应合成出蔗糖硬脂酸酯。详细考察了该合成反应过程中乳化剂、催化剂用量,反应温度,原料配比,反应时间等因素对蔗糖硬脂酸酯产率的影响,得出了较佳合成工艺条件,即硬脂酸乙酯:蔗糖摩尔比为2.15:1,乳化剂与蔗糖质量比为0.1:1,催化剂与反应物料质量比为0.14:1,反应温度-120℃,压力-4.35kPa,反应时间-3.5h。以蔗糖计,蔗糖酯产率约75.2%。此外,还把蔗糖硬脂酸酯制成易挥发衍生物,建立了分析其组成的气相色谱方法。 相似文献
12.
This work studies the application of KNO3/CaO catalyst in the transesterification reaction of triglycerides with methanol. The objective of the work was characterizing the methyl esters for its use as biodiesel in compression ignition motors. The variables affecting the methyl ester yield during the transesterification reaction, such as, amount of KNO3 impregnated in CaO, the total catalyst content, reaction temperature, agitation rate, and the methanol/oil molar ratio, were investigated to optimize the reaction conditions.The evolution of the process was followed by gas chromatography, determining the concentration of the methyl esters at different reaction times. The biodiesel was characterized by its density, viscosity, cetane index, saponification value, iodine value, acidity index, CFPP (cold filter plugging point), flash point and combustion point, according to ISO norms. The results showed that calcium oxide, impregnated with KNO3, have a strong basicity and high catalytic activity as a heterogeneous solid base catalyst.The biodiesel with the best properties was obtained using an amount of KNO3 of 10% impregnated in CaO, a methanol/oil molar ratio of 6:1, a reaction temperature of 65 °C, a reaction time of 3.0 h, and a catalyst total content of 1.0%. In these conditions, the oil conversion was 98% and the final product obtained had very similar characteristics to a no. 2 diesel, and therefore, these methyl esters might be used as an alternative to fossil fuels. 相似文献
13.
Synthesis of FAME from Brassica carinata oil to produce biodiesel was accomplished using potassium hydroxide as the catalyst. A factorial design of experiments and
a central composite design were used. The variables chosen were: type of Brassica carinata oil, initial catalyst concentration, and temperature; and the responses were FAME purity and yield. The type of B. carinata oil included high-erucic B. carinata (HEBC) and lowerucic B. carinata (LEBC) varieties. The results show that the type of B. carinata oil does not affect the purity and yield of FAME. However, HEBC oil is more suitable for biodiesel production because its
iodine value is lower and within the European Union specifications. The initial catalyst concentration is the most important
factor, having a positive influence on FAME purity but a negative effect on FAME yield. The temperature has a significant
positive effect on FAME purity and a significant negative influence on FAME yield. Second-order models were obtained to predict
FAME purity and yield as a function of catalyst concentration and temperature for HEBC oil methanolysis. The best conditions
for this process are 25°C, and 1.2–1.5 wt% for the catalyst concentration. 相似文献
14.
环氧大豆油无溶剂法合成研究 总被引:14,自引:0,他引:14
介绍了一种环氧大豆油的无溶剂法合成工艺.通过正交实验方法优选了合成工艺条件;讨论了甲酸用量、双氧水用量及滴加速度、催化剂用量、反应温度、反应时问等对产物环氧值的影响。 相似文献
15.
低温费托合成技术因具有产品质量性好、反应耗能低、生产能力大且催化剂种类广泛等优点在煤化工领域备受关注,低温费托合成的蜡油产品可通过加氢裂化精制获取高品质清洁油品,具有巨大的应用价值。本文首先阐述了费托合成的产物特性,分析了加氢裂化过程的反应特点、双功能催化剂的碳正离子反应机理及蜡油主要反应历程。在此基础上,着重综述了蜡油加氢裂化双功能催化剂的研究进展,讨论了活性金属组分、载体以及助剂对加氢裂化过程的影响,分析表明活性金属的负载量、载体的酸量和孔道结构对催化性能有极大影响,合理优化和平衡加氢金属活性位和裂解酸性位是确保蜡油加氢裂化催化剂活性的关键。更为重要的是,基于分子筛载体的择形效应,实现载体多级孔结构和活性位的理性集成无疑会促进蜡油加氢产物的合理分布。 相似文献
16.
In this study, transesterification of rapeseed oil using subcritical methanol conditions was studied. The objective of the work was characterizing the methyl esters for its use as biodiesel in compression ignition motors. The variables affecting the methyl ester yield during the transesterification reaction, such as, the catalyst type and content, reaction temperature and pressure, the presence of hexane as co-solvent, the methanol oil molar ratio and the methanol hexane molar ratio were investigated to optimize the reaction conditions. The evolution of the process was followed by gas chromatography, determining the concentration of the methyl esters at different reaction times. The biodiesel was characterized by its density, viscosity, saponification value, iodine value, acidity index and water content, according to ISO norms. High methyl ester yield and fast reaction rate could be obtained even if the reaction pressure was relatively low, which is quite favorable to the production of biodiesel in industry. 相似文献
17.
Relative oxidative stabilities of sperm whale oil and eight wax ester preparations were determined by comparing oxygen uptake
profiles that had been corrected for ester volatility. Wax esters with unsaturation near the ester bond, even though more
volatile, are as stable toward oxidation as those with double bonds near the center of each aliphatic chain. 相似文献
18.
固体超强酸SO_4~(2-)/TiO_2催化合成利巴韦林缩合物研究 总被引:1,自引:0,他引:1
以1,2,4-三氮唑-3-羧酸甲酯和1,2,3,5-四-O-乙酰基-β-D-呋喃核糖为原料,在催化剂固体超强酸SO42-/TiO2的作用下得到了1-(2,3,5-三-O-乙酰基-β-D-呋喃核糖基)-1H-1,2,4-三唑-3-羧酸甲酯,简称利巴韦林缩合物。它是广谱抗病毒药物利巴韦林的重要中间体。通过对影响反应的多种因素进行研究以及反应条件的优化,结果表明:当催化剂为固体超强酸SO42-/TiO2、催化剂用量为12%、1,2,4-三氮唑-3-羧酸甲酯和1,2,3,5-四-O-乙酰基-β-D-呋喃核糖投料摩尔比为1.05:1、反应温度控制在100℃~110℃、反应时间为2h、甲醇重结晶,所得产物收率为87.0%,纯度99.5%(HPLC)。该反应方法催化剂易制备,催化效率较高,容易循环使用,不污染环境,有一定的再生能力,易从产品中除去,操作过程简便,产品色泽好、纯度高。 相似文献
19.
以亚麻油经醇解反应得到的亚麻油脂肪酸甲酯为原料,在催化剂存在下,用间歇常压聚合法,合成了二聚酸甲酯。用正交试验设计考察了反应温度,催化剂用量,反应时间对二聚反应产物收率的影响,找到了最佳反应条件。 相似文献
20.
Denise Aparecida Zempulski Caroline Portilho Trentini Maria Cristina Milinsk Helton Jos Alves Camila da Silva 《European Journal of Lipid Science and Technology》2020,122(5)
The efficiency of a heterogeneous potassium fluoride (KF)/clay catalyst in continuous ester production from residual frying oil using pressurized ethanol is evaluated. Reactions without catalysts are conducted to determine the effect of the catalyst on ester yield. To verify the performance of the catalyst, the reactions are conducted for 3 h with determination of the ester yield every 30 min and characterization of the catalyst after each reaction. The influence of the temperature, catalyst mass used in the catalytic bed, and the residence time are evaluated. KF/clay is found to be efficient in ester synthesis and provides better results compared with non‐catalytic reactions and the formation of esters is favored on increasing the temperature. The ester yields remain stable over time at 275 and 300 °C but at 225 and 250 °C the yields decrease by 48.42% and 38.40%, respectively. This may be due to the lower diffusion coefficient at these temperatures, implying that the reaction occurs preferentially at the catalyst surface. There is an increase in yield with an increase in the catalyst mass up to 2 g. The catalyst maintains its morphological characteristics after the reaction and the average mass loss in each reaction is <8%. Practical Applications: Transesterification at high temperature under pressurized conditions has great potential in biodiesel production, due to the efficiency in obtaining esters in short reaction times. In addition, the use of inexpensive and easily obtained clay‐based catalysts contributes to higher yields and allows milder operating conditions. These factors make it possible to obtain biodiesel using a low‐cost raw material (residual frying oil), under pressurized conditions, which will be of interest worldwide due to the various benefits linked to its use. 相似文献