共查询到20条相似文献,搜索用时 15 毫秒
1.
E. O. I. Banigo A. Ogunlesi O. Ofi 《Journal of the American Oil Chemists' Society》1977,54(12):593-594
The traditional processing system of coconut oil, comprising grating of coconut meats, extraction with boiling water, cooling, followed by skimming off the cream, and heating it to dryness to give coconut oil, has been adapted for the manufacture of palm kernel oil. Palm kernels were crushed in a laboratory hammer mill, extracted with several lots of boiling water, cooled, the resulting cream skimmed off, and heated to dryness to yield palm kernel oil. A comparison of existing traditional and new adapted processing systems showed that the yield palm kernel oil obtained in both cases was about the same. Furthermore, the specific gravity, melting point, refractive index, and saponification number were similar, but the moisture content, acid value, color, and odor were dissimilar. 相似文献
2.
Steven J. Laning 《Journal of the American Oil Chemists' Society》1985,62(2):400-407
3.
Ca and Zn mixed oxide as a heterogeneous base catalyst for transesterification of palm kernel oil 总被引:3,自引:0,他引:3
Chawalit Ngamcharussrivichai Prangsinan Totarat Kunchana Bunyakiat 《Applied Catalysis A: General》2008,341(1-2):77-85
Transesterification of palm kernel oil with methanol over mixed oxides of Ca and Zn has been investigated batchwise at 60 °C and 1 atm. CaO·ZnO catalysts were prepared via a conventional co-precipitation of the corresponding mixed metal nitrate solution in the presence of a soluble carbonate salt at near neutral conditions. The catalysts were characterized by using techniques of X-ray diffraction (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TGA). The results indicated that the mixed oxides possess relatively small particle sizes and high surface areas, compared to pure CaO and ZnO. Moreover, the combination of Ca and Zn reduced the calcination temperature required for decomposition of metal carbonate precipitates to active oxides. Influences of Ca/Zn atomic ratio in the mixed oxide catalyst, catalyst amount, methanol/oil molar ratio, reaction time, and water amount on the methyl ester (ME) content were studied. Under the suitable transesterification conditions at 60 °C (catalyst amount = 10 wt.%, methanol/oil molar ratio = 30, reaction time = 1 h), the ME content of >94% can be achieved over CaO·ZnO catalyst with the Ca/Zn ratio of 0.25. The mixed oxide can be also applied to transesterification of palm olein, soybean, and sunflower oils. Furthermore, the effects of different regeneration methods on the reusability of CaO·ZnO catalyst were investigated. 相似文献
4.
Ultrasonic-assisted biodiesel production process from palm oil using alkaline earth metal oxides as the heterogeneous catalysts 总被引:1,自引:0,他引:1
Hamed Mootabadi 《Fuel》2010,89(8):1818-1825
The ultrasonic-assisted transesterification of palm oil in the presence of alkaline earth metal oxide catalysts (CaO, SrO and BaO) was investigated. Batch process assisted by 20 kHz ultrasonic cavitation was carried out to study the effect of reaction time (10-60 min), alcohol to palm oil molar ratio (3:1-15:1), catalysts loading (0.5-3%) and varying of ultrasonic amplitudes (25-100%). The activities of the catalysts were mainly related to their basic strength. The catalytic activity was in the sequence of CaO < SrO < BaO. At optimum conditions, 60 min was required to achieve 95% yield compared to 2-4 h with conventional stirring. Also, the yields achieved in 60 min increased from 5.5% to 77.3% (CaO), 48.2% to 95.2% (SrO), and 67.3% to 95.2 (BaO). Fifty percentage amplitude of ultrasonic irradiation was deemed the most suitable value and physical changes on the catalysts after the ultrasonic-assisted reaction were successfully elucidated. BaO catalyst underwent relatively more severe activity drop in the catalyst reusability test. Catalysts dissolution was found to be mainly responsible for activity drop of the reused catalysts, especially with BaO catalyst. 相似文献
5.
A series of Pt-Co supported on γ-alumina have been prepared from acetylacetonate precursors with 2 wt% as total metal loading
and different atomic contents. The catalysts were characterized by hydrogen chemisorption, TPR, TEM, XPS and they were tested
in two different reactions: methylcyclohexane dehydrogenation and n-butane hydrogenolysis. The results have shown that platinum
is in reduced state and cobalt is mainly in an oxidized state. Additionally, TEM results evidence an increase in the particle
size as cobalt content is increased, in agreement with chemisorption results. Monometallic platinum and cobalt supported catalysts
showed large differences in the dehydrogenation of methylcyclohexane, while the bimetallic catalysts have activities in the
same order of magnitude with respect to the pure platinum catalyst. In n-butane hydrogenolysis all the catalysts show a large
decrease in activity compared to other, previously studied Pt-based bimetallic catalysts.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
7.
Roy J. de Vries 《Journal of the American Oil Chemists' Society》1984,61(2):404-407
Malaysia produces ca. 65% of the world’s palm oil, or (in 1982) ca. 3,500,000 metric tons. By 1985, this will increase to
80% of world production, or ca. 4,800,000 metric tons. Palm oil products are refined, bleached and deodorized oil for edible
purposes, palm olein for edible use, palm stearin for edible or industrial use, and the acid oil or fatty acid distillate
for industrial uses. The Malaysian processors naturally want to upgrade the products as much as possible. 相似文献
8.
Richard A. Reck 《Journal of the American Oil Chemists' Society》1985,62(2):355-365
Palm, palm kernel and coconut oils are sources of fatty acids that can be converted to other oleochemicals that have many
applications. This paper describes manufacturing procedures, product characteristics and uses for many fatty acids, alcohols,
primary amides, monosubstituted amides, diamides, disubstituted amides, nitrites, primary amines, secondary amines, tertiary
amines, diamines, quaternary ammonium compounds, amphoterics, amine oxides and polyoxyalkylene alkylamines. 相似文献
9.
10.
N. Sreedhara C. Arumughan C. S. Narayanan 《Journal of the American Oil Chemists' Society》1992,69(10):1015-1018
A novel method has been developed for the removal of the thin, dark-brown skin, called testa, from the palm kernel of the
oil palm (Elaeis guineensis) by chemical treatment. Studies carried out for this purpose included physical or mechanical means, dry or wet heat, solvents
and other chemicals. Of the procedures tried, treatment with hydrochloric acid (HCl) resulted in complete removal of the testa,
producing a pearl-white palm kernel. All other treatments were found to be ineffective. Based on our laboratory studies, semi-large-scale
trials were made with 4N HCl for continuous dehulling of palm kernel in an abrasive peeling machine for the preparation of
superiorgrade kernel flour and oil. 相似文献
11.
Yun-Xiao Zhang Jing-Chao Tao Le Wang 《Journal of the American Oil Chemists' Society》2006,83(7):659-662
A new method has been proven successful to obtain high-purity arachidonic acid (AA), an important human nutrient, from fungal
single-cell oil via Al2O3-supported CuSO4 column chromatography; the stationary phase is stable and readily reusable. In the first step, the mixed FA extracted from
saponified fungal single-cell oil, containing 47.3% AA, were purified via urea inclusion to afford a fraction of PUFA containing 74.9% AA with an 85.9% yield. The enriched AA fraction was subsequently
passed through an Al2O3-supported CuSO4 column with a hexane/acetone eluent to provide AA with 90.8% purity at a 46.5% yield. The total yield for the two-step process
was 39.9%. 相似文献
12.
Aluminas pretreated with pure water (pseudo-hydrothermal treatment) and very dilute basic aqueous solutions were used as catalysts for CO hydrogenation. Pseudo-hydrothermal treatment results in an apparent enhancement of ethylene selectivity at elevated temperature (>673 K). The active sites seem to be coordinatively unsaturated metal and oxygen counterions (Lewis acid and base pair), which are very probably located on the most external surface of the alumina and can be coordinatively saturated by calcination in air. The precursors of the active sites probably originate from a very thin layer of boehmite beyond XRD detecting ability. They can be generated by both pseudo-hydrothermal treatment and dilute basic aqueous solution treatment of alumina. 相似文献
13.
The kinetics of palm oil and mustard oil transesterification are compared. Transesterification of palm oil and mustard oil using KOH as a catalyst was performed at various reaction temperatures ranging from 40 to 60°C. The reaction steps are reversible and transesterification is favoured at elevated temperatures. The reaction step of triglyceride to diglyceride is the rate determining step (RDS) that controls kinetics of overall transesterification with activation energies of 30.2 and 26.8 kJ/mol for palm oil and mustard oil transesterification, respectively. It is found that percentage of saturated compounds play a vital role on transesterification kinetics. © 2011 Canadian Society for Chemical Engineering 相似文献
14.
分别以超重力法制备的纳米纤维状γ-Al2O3和普通γ-Al2O3为载体,采用浸渍法制备了相同组分LaCeCuMn的纳米稀土催化剂,并应用微反活性评价装置测试了对CO和C3H8的氧化活性。利用XRD,TEM,BET等手段,分析了产品的结构和粒子形貌。实验结果表明,与以普通γ-Al2O3为载体的催化剂相比,催化剂活性组分在纳米纤维状γ-Al2O3载体上分散比较均匀,平均粒径为15~20nm,为纳米级催化剂;CO和C3H8氧化反应中起燃温度分别可以达到161,186℃,且二者的最终转化率均在99%以上。 相似文献
15.
D. Schanke A. M. Hilmen E. Bergene K. Kinnari E. Rytter E. Ådnanes A. Holmen 《Catalysis Letters》1995,34(3-4):269-284
The influence of water on alumina-supported cobalt catalysts has been studied. The deactivation of supported Co catalysts was studied in a fixed-bed reactor using synthesis gas feeds containing different concentrations of water vapour. Supporting model studies were carried out using H2O/H2 feeds in conjunction with XPS and gravimetry. Rapid deactivation occurs on Re-promoted CO/Al2O3 catalysts when H2/CO/H2O feeds are used, whereas unpromoted CO/Al2O3 shows more stable activity. The results from the gravimetric studies suggest that only a small fraction of the bulk cobalt metal initially present reoxidizes to cobalt oxide during reaction. However, the XPS results indicate significant reoxidation of surface cobalt atoms or highly dispersed cobalt phases, which is likely to be the cause of the observed deactivation. Rhenium is shown to have a marked effect on the extent of reoxidation of alumina-supported cobalt catalysts. 相似文献
16.
《The Journal of Supercritical Fluids》2001,19(2):141-148
The use of biocatalysts in supercritical CO2 (SCCO2) has received widespread attention in recent years. Biocatalysts have the advantage of substrate specificity under mild reaction conditions and SCCO2 has several advantages over liquid solvents such as high solute diffusivities and low viscosity, which can accelerate mass transfer-limited enzymatic reactions. Concerning the enzymatic alcoholysis of vegetable oils, very little experimental data have been reported in the literature. Also, to the best of our knowledge, there is no comprehensive study available comparing conventional and supercritical media for this reaction. In this context, the main objective of this work is to compare enzymatic ethanolysis of palm kernel oil taking place in both SCCO2 and in n-hexane as solvents. For this purpose, a Taguchi experimental design with two levels and four variables was adopted for each system to allow the investigation of the influence of process variables on the reaction conversion and on the enzyme activity. 相似文献
17.
Saeid Baroutian Abdul Aziz Abdul Raman Nik Meriam Nik Sulaiman 《Fuel Processing Technology》2010,91(11):1378-8929
In this study, potassium hydroxide catalyst supported on palm shell activated carbon was developed for transesterification of palm oil. The Central Composite Design (CCD) of the Response Surface Methodology (RSM) was employed to investigate the effects of reaction temperature, catalyst loading and methanol to oil molar ratio on the production of biodiesel using activated carbon supported catalyst. The highest yield was obtained at 64.1 °C reaction temperature, 30.3 wt.% catalyst loading and 24:1 methanol to oil molar ratio. The physical and chemical properties of the produced biodiesel met the standard specifications. This study proves that activated carbon supported potassium hydroxide is an effective catalyst for transesterification of palm oil. 相似文献
18.
D. A. Morgan D. B. Shaw M. J. Sidebottom T. C. Soon R. S. Taylor 《Journal of the American Oil Chemists' Society》1985,62(2):292-299
The results presented in the literature, which attempt to elucidate the mechanisms by which triglyceride oils are bleached
by earths, are reviewed. The impact of this work and how the mechanistic proposals affect changes in oil properties are considered,
with particular emphasis on the needs of the palm oil processor. Important properties include color, metals and phosphorus
content and oxidative stability of the oil.
Investigations made in our own laboratories have been aimed at elucidating the effect of varying physical and chemical properties
of the bleaching earth on the quality of bleached and deodorized oils. Techniques used in this work are pore-size distribution,
surface area, scanning and transmission electron microscopy and a variety of chemical and X-ray analysis methods.
The ability to vary such parameters in montmorillonite clays by alteration of process conditions to give materials with specific
performance characteristics is demonstrated.
Comparisons are made between acid-activated montmorillonites and other clay types. 相似文献
19.
Various unpromoted and alkali (earth) promoted gold catalysts were characterized by means of XRD, HRTEM, DR/UV–Vis and TPR.
Based on the results we conclude that metallic Au is the active species in CO oxidation and that the reduction of Au3+ to Au0 proceeds below 200 °C. Pretreatment at mild temperatures, viz. 200 °C, results in the highest catalytic performance of Au/Al2O3 in low-temperature CO oxidation. Alkali (earth) metal oxide additives are most probably structural promoters. The best promoting
effect is found for BaO. 相似文献
20.
Alum has been taken beyond its traditional roles as a water treatment chemical and a confectionary additive to a new role as a catalytic precursor in biodiesel production. Its catalytic potentials were empirically proved via palm oil transesterification with methanol and application of solid state instrumental characterization techniques. The catalyst was very clean, efficient, simple and cheap to produce, and could be clearly separated from the reaction products. When the reaction was carried out under the conditions of catalyst to oil ratio of 7.09 wt%, reaction time of 12 h and temperature of 170 °C, methanol to oil molar ratio of 18:1 and catalyst preconditioned at 550 °C, the yield of fatty acid methyl ester (FAME) obtained was 92.5 wt%. 相似文献