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1.
ABSTRACT

Glycolipids prepared from palm kernel oil, PKO, in tropical regions represent an excellent opportunity to develop new surfactant formulations for cosmeceutical and pharmaceutical applications while contributing to sustainable economies. Here we report the synthesis of a new mannoside obtained from palm kernel oil, aManPKO, and we characterise its thermotropic properties by using DSC, POM, SAXS, WAXS, FT-IR and broadband dielectric spectroscopy. aManPKO exhibits a monotropic smectic phase with a partially interdigitated bilayer structure, similar to its major unsaturated component, the oleyl mannoside with a C18:1 monounsaturated alkyl chain. The smectic phase of aManPKO vitrifies below room temperature, which is associated to the C18:1 component, but also to the activation of short-range motions, ~4 Å, by cleavage of strong hydrogen bonding between the polar heads of the mannosides. The stability of the liquid crystal phase, on the other hand, is linked to the presence of weak hydrogen bonding, whose breakage leads to the activation of long rate motions in the range of the layer distances, ~39 Å.  相似文献   

2.
Supercritical fluid extraction (SFE), which has received much interest in its use and further development for industrial applications, is a method that offers some advantages over conventional methods, especially for the palm oil industry. SC-CO? refers to supercritical fluid extraction (SFE) that uses carbon dioxide (CO?) as a solvent which is a nontoxic, inexpensive, nonflammable, and nonpolluting supercritical fluid solvent for the extraction of natural products. Almost 100% oil can be extracted and it is regarded as safe, with organic solvent-free extracts having superior organoleptic profiles. The palm oil industry is one of the major industries in Malaysia that provides a major contribution to the national income. Malaysia is the second largest palm oil and palm kernel oil producer in the World. This paper reviews advances in applications of supercritical carbon dioxide (SC-CO?) extraction of oils from natural sources, in particular palm oil, minor constituents in palm oil, producing fractionated, refined, bleached, and deodorized palm oil, palm kernel oil and purified fatty acid fractions commendable for downstream uses as in toiletries and confectionaries.  相似文献   

3.
In this study, new biopolymer nanocomposites have been prepared. Fatty nitrogen compounds (FNCs); fatty amide (FA), fatty hydroxamic acid (FHA), and carbonyl difatty amide (CDFA), which were synthesized from palm oil, have been used as one of organic compounds to modify natural clay (sodium montmorillonite). The clay modification was carried out by stirring the clay particles in an aqueous solution of FA, FHA, and CDFA by which the clay layer distance increases from 1.23 to 2.71, 2.91 and 3.23 nm, respectively. The modified clay was then used in the preparation of the polylactic acid/epoxidized palm oil (PLA/EPO) blend nanocomposites. The interaction of the modifier in the clay layer was characterized by X-ray diffraction (XRD), and Fourier transform infrared (FTIR). Elemental analysis was used to estimate the presence of FNCs in the clay. The nanocomposites were synthesized by melt blending of the modified clay and PLA/EPO blend at the weight ratio of 80/20. The nanocomposites were then characterized using XRD, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and tensile properties measurements. The XRD and TEM results confirmed the production of nanocomposites. PLA/EPO modified clay nanocomposites show higher thermal stability and significant improvement of mechanical properties in comparison with those of the PLA/EPO blend.  相似文献   

4.
The diversity of raw materials and technological routes employed in the biodiesel production has resulted in products with different chemical properties. This non-uniformity in the biodiesel composition may influence to the fuel quality. The aim of this study was to evaluate biodiesel blends of passion fruit and castor oil in different proportions and their thermal stability. Biodiesel blends of passion fruit and castor oil presented parameters in the standards of the Petroleum, Natural Gas and Biofuels National Agency. The TG curves indicated that castor oil biodiesel was more stable. Passion fruit biodiesel has a high content of oleic and linoleic acids, which are more susceptible to oxidation. Biodiesel blend of passion fruit and castor oil 1:1 increased the thermal stability in relation to passion fruit biodiesel. Biodiesel blend of passion fruit and castor oil 1:2 presented higher thermal stability, because castor oil has a high content of ricinoleic acid.  相似文献   

5.
Journal of Thermal Analysis and Calorimetry - This study aims to investigate the thermal conductivity, viscosity and thermal degradation of naphthenic-based mineral oil, palm oil methyl ester...  相似文献   

6.
Enhanced oil recovery process is based on the injection of chemical products (e.g. polymers, surfactants, gases) or thermal energy (originating from the injection of e.g. steam, hot water, in situ combustion) to recover crude oil. One of these processes use polymer solution to mobilize the oil in the reservoir. In this work the thermal decomposition kinetic of xanthan gum, guar gum and a blend (50/50 mass/mass%) was studied according to Ozawa–Flynn–Wall method. According to the kinetic analysis, the studied systems were copmpatible. The rheological behavior of the samples was studied in distilled water and seawater at different temperatures. Only the blend was studied in distilled water presented synergism (enhancement in material properties like stability and viscosity) which was confirmed through rheology.  相似文献   

7.
油棕废弃物热解的TG-FTIR分析   总被引:8,自引:3,他引:8  
利用热重分析(TGA)和傅里叶红外光谱(FTIR)联用技术对油棕废弃物的热解特性及其气体产物的释放特性进行了研究,采用一级反应计算了油棕废弃物的热解动力学参数。研究表明,油棕废弃物较易于热解,失重集中在220℃~400℃,其热解活化能较小,约为60kJ/mol;气体产物的析出与生物质的热解失重有着相似的特性,气体产物主要在200℃~400℃析出,主要成分为H2O、CO2、CO、CH4和有机碳水化合物的混合物, 其中CO2和有机混合物的析出温度较低,而CO和CH4的析出温度相对较高。随着温度的进一步升高(>400℃),除少量的CO2和CO外,无其他气体产物析出。气体产物的析出量与生物质样品的化学组成和结构有关,CO2和有机混合物的析出与生物质的热解失重曲线(DTG)有着相似的特性,是引起油棕废弃物热解失重的主要原因。  相似文献   

8.
以棕榈油为研究对象,分别与甲醇、乙醇、异丙醇和异丁醇进行酯交换反应制备了不同酯基结构的生物柴油。利用差示扫描量热仪和应力控制流变仪分析了不同酯基结构棕榈油生物柴油的结晶行为和低温流变性能,同时分析了酯基结构对生物柴油的氧化稳定性,40℃时的动力黏度、20℃时的密度等重要性质的影响。结果表明,随着醇的碳链长度的增加,棕榈油生物柴油的析蜡点和胶凝点均降低,特别是棕榈油异丁酯的析蜡点和胶凝点分别降低到了-2.57和-8.09℃,低温流动性得到了明显改善,且氧化诱导期略有延长,氧化稳定性有所改善。生物柴油的密度和黏度随着酯基结构的不同而有所变化,但其数值都符合中国生物柴油标准。  相似文献   

9.
The oil palm sector is one of the major plantation industries in Malaysia. Palm kernel cake is a byproduct of extracted palm kernel oil. Mostly palm kernel cake is wasted or is mixed with other nutrients and used as animal feed, especially for ruminant animals. Recently, palm kernel cake has been identified as an important ingredient for the formulation of animal feed, and it is also exported especially to Europe, South Korea, and Japan. It can barely be consumed by nonruminant (monogastric) animals owing to the high percentages of hemicellulose and cellulose contents. Palm kernel cake must undergo suitable pretreatment in order to decrease the percentage of hemicellulose and cellulose. One of the methods employed in this study is fermentation with microorganisms, particularly fungi, to partially degrade the hemicellulose and cellulose content. This work focused on the production of enzymes by Aspergillus niger and profiling using palm kernel cake as carbon source.  相似文献   

10.
This study shows the synthesis, characterization, and evaluation of the effect of organophosphate antioxidant on the thermo-oxidative degradation of a mineral oil. The organophosphate was synthesized by nucleophilic substitution (SN2) of hydrogenated cardanol. For this study, were employed thermogravimetry, derivative thermogravimetry, differential scanning calorimetry, and differential thermal analysis techniques. The results showed that organophosphate contributed for thermo-oxidative stability of mineral oil (initial decomposition temperature (IDT) mineral oil: 91.28 °C < IDT mineral oil + organophosphate (1%): 156.42 °C). The organophosphate obtained shows significant thermal stability when compared with other compound of the same class (diphenyl phosphate).  相似文献   

11.
In the present study, chemical-physical properties of nanofibers isolated from rubberwood (Hevea brasiliensis) and empty fruit bunches (EFB) of oil palm (Elaeis guineensis) were analyzed by microscopic, spectroscopic, thermal and X-ray diffraction methods. The isolation was achieved using chemo-mechanical processes. Microscopy study showed that the diameters of the nanofibers isolated from the EFB ranged from 5 to 40 nm while those of the nanofibers isolated from rubberwood had a wider range (10–90 nm). Fourier transform infrared spectroscopy study demonstrated that almost all the lignin and most of the hemicellulose were removed during the chemical treatments. X-ray diffraction analysis revealed that the crystallinity of the studied nanofibers increased after the chemo-mechanical isolation process. The results of thermogravimetric analysis showed that the nanofibers isolated from both sources had higher thermal stability than those of the bleached pulp and untreated fibers.  相似文献   

12.
Bentonite filled polypropylene composites were prepared using a Polydrive Thermo Haake, internal mixer at 180 °C and at 50 rpm of rotor speed. Effect of compatibilisers on mechanical, thermal, water absorption and morphological properties of bentonite filled polypropylene composites was investigated. Two types of compatibilisers namely, palm oil fatty acid additive (POFA) and polypropylene grafted-maleic anhydride (PPMAH) have been used in this study. The mixing of the composites improved with the addition of POFA. The impact strength and elongation at break increased with the presence of both compatibilisers whilst, tensile strength and Young's modulus improved only with addition of PPMAH. Morphological investigation using SEM revealed that the improvement in impact strength and elongation at break was due to enhancement of the interfacial adhesion between bentonite and PP. The thermal stability of bentonite filled PP improved with the incorporation of POFA and PPMAH. Less percentage of water absorption has been observed in PP-bentonite system with PPMAH.  相似文献   

13.
Flammability of recycled polypropylene (PP)/low density polyethylene (LDPE)/high density polyethylene (HDPE) ternary blends containing date palm fibres is investigated in this study. Melt blending is used for the composite preparation and the palm fibres induce good mechanical strength to the blend composites. The effect of flame retardant magnesium hydroxide, is studied through the limiting oxygen index analysis and cone calorimeter studies. Morphology of the palm fibres in presence of fire retardant reveals interesting facts of base hydrolysis. Since the polymers used are recycled ones and the fibres are obtained from the date palm leaves, the whole composite manufactured stands as low cost, less energy consuming and environmental friendly. Though the flame retardant reduced the mechanical properties, the palm fibres strengthened the whole composite thus helping to achieve the flame retardancy and mechanical properties simultaneously. Flame retardancy is correlated with the thermal degradation and thermal conductivity of the blend fibre composites as well.  相似文献   

14.
In this study, a series of styrene‐b‐ethylene‐co‐butylene‐b‐styrene copolymer (SEBS)/polypropylene (PP)/oil blends with different kinds of oil composition was developed through melt blending. The effect of oil with different composition and properties on its phase equilibrium and “redistribution” in multiphasic SEBS elastomer was systematically studied for the first time. Moreover, an integral influencing mechanism of oil composition on the structure and properties of SEBS/PP/oil blends was also put forward. The mineral oil was mainly distributed in ethylene/butylene (EB)/PP phase, which greatly enhanced the processing flowability of SEBS/PP/oil blends. With increasing oil CN content, a redistribution of oil appeared and excess naphthenic oil (NO) entered the interphase of soft and hard phases. The dynamic mechanical thermal analysis (DMTA) analysis indicated that the polystyrene (PS) phase was plasticized, which also helped to improve the processing fluidity of blends. However, the plasticizing of physical cross‐linking point PS resulted in a decrease in mechanical strength and thermal stability. Small‐angle X‐ray scattering (SAXS) and transmission electron microscope (TEM) results showed that PS phase (45 nm to 55 nm) cylindrically distributed in EB/PP/oil matrix, the excess NO in the interphase enlarged the distance between PS phase and widen the escape channel for oil migration. At over 45% oil CN content, the electron density difference between soft and hard phases reduced to the minimum, same as TgPS, indicating a deeper plasticizing effect. The PS phase swelled and exhibited elastic behavior; thus, the force could be uniformly transferred between two phases. Importantly, a recover in strength and thermal stability was observed in O‐5 blend. This work significantly filled the gap of studies in oil‐extended thermoplastic elastomers (TPEs), exhibiting great theoretical guiding significance and application value.  相似文献   

15.
Even not being described in the EN 14112 standard, PDSC has been used for the determination of the biodiesel oxidative stability, by OIT and OT measurements. In this study, biodiesel blends were obtained by mixing soybean (BES) and castor (BEM) ethyl esters and its induction periods were measured by Rancimat and PDSC. The blends (BSM X ) showed intermediate values of OSI, OT, and OIT, compared with BES and BEM. Although, the molar fraction of the components varied linearly in BSM X , OSI, OT, and OIT values increased exponentially in relation to the castor biodiesel amount in the blends. Introduction of castor oil biodiesel increased the blend stability, so the BSM30 blend reached the OSI limit of 6 h. OSI, OIT, and OT showed a high-linear correlation, pointing out that PDSC can be used in the analysis of this kind of biodiesel, with a smaller sample and analysis time, as compared to Rancimat. The use of biodiesel blends was a good alternative in the correction of the oxidative stability of the final product without the need of antioxidant addition.  相似文献   

16.
In this study, the effects of epoxidized palm oil (EPO) on the mechanical and morphological properties of a blend of two types of biodegradable polymer, poly(lactic acid) (PLA) and polycaprolactone (PCL), were investigated. The solution-casting process, with chloroform as a solvent, was used to prepare samples. Addition of EPO reduced the tensile strength and modulus but increased elongation at break for the PLA–PCL blend. The highest elongation at break was observed for the blend with 10 % (w/w) EPO content. Scanning electron microscopy (SEM) indicated that the fractured surface morphology of the PLA–PCL blend became more stretched and homogeneous in PLA–PCL–EPO. Possible interactions between the PLA–PCL blend and EPO were also characterized by use of Fourier-transform infrared (FTIR) spectroscopy. Thermal stability was studied by differential scanning calorimetry and thermogravimetric analysis. The results from FTIR and SEM revealed that the miscibility of the PLA–PCL blend was improved by addition of EPO.  相似文献   

17.
This article reflects on the Federation of Asian Chemical Societies (FACS) Citation Award Lecture delivered in the Industrial Technology Research Institute Symposium on CO2 Utilization and Green Technology during the 18th Asian Chemical Congress held in Taipei, December 12, 2019. Malaysia produces sizable amounts of palm oil and palm kernel oil, with palm fronds and tree trunks as the main waste. At the Malaysia Japan International Institute of Technology, the biomass was decomposed to produce fine chemicals, used as substrate for mushroom growth, and converted to bio-coke for heat energy. A notable difference has been found regarding the emission of greenhouse gases from a natural peat forest and those from the oil palm plantation converted from peatlands, where in the palm plantation, water table is lowered and aerobic processes occurs, resulting in more CO2 being released compared to CH4. The introduction of fertilizers to the plantation resulted in more N2O being released. The team has also pioneered a project to plant temperate vegetables. Cooling pipes (16–18°C with circulating water cooled by chiller) were embedded within each thermal conditioning soil plot. Lettuce and radish, the experimental plants, showed good growth in the thermal conditioning soil due to nitrogen-fixing bacteria, which were destroyed at a higher temperature.  相似文献   

18.
The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network.  相似文献   

19.
Epoxidized sunflower oil (ESO) was utilized as a plasticizer for polylactic acid (PLA) using chloroform as a solvent by a solution casting process at various ratios of PLA to ESO. Fourier-transform infrared (FTIR) spectroscopy was used to identify the functional groups of PLA, ESO, and PLA/ESO blends. Thermal stability and mechanical and morphological properties of the blends were investigated by thermogravimetric analysis, tensile property measurements, and scanning electron microscopy technique, respectively. The FTIR spectra indicate that there are some molecular interactions by intermolecular hydrogen bonding between PLA and ESO. PLA/ESO blends show high thermal stability and significant improvement of mechanical properties compared with pure PLA. The highest elongation at break was obtained when the ratio of the PLA/ESO blend was 80/20. Morphological results of PLA/ESO blends show that ESO was well miscible with PLA.  相似文献   

20.
This study investigates the biosynthesis and characterization of P(3HB-co-3HV-co-3HHx) terpolymer from mixtures of palm kernel oil and 3HV-precursors by using recombinant Cupriavidus necator PHB4/pBBREE32d13. Sodium valerate and propionate have been evaluated for the generation of 3HV monomers. The feeding time of these precursors was a crucial factor that significantly affected the 3HV molar fractions, which ranged from 2 to 60 mol%. Sodium valerate was generally the better precursor in initiating the accumulation of 3HV monomers while maintaining high cell dry weight (7.9 g/L) and good PHA accumulation (79 wt%). However, the 3HHx molar fractions in the terpolymers at 72 h were consistent at about 2-7 mol%. P(3HB-co-3HV) copolymers have been known to exhibit approximately the same degree of crystallinity throughout a wide range of 3HV composition. Interestingly, in this study, terpolymers containing 58 mol% 3HB, 39 mol% 3HV and 3 mol% 3HHx showed elastomeric behavior. This study demonstrates the suitability of palm kernel oil as the main carbon source and both sodium propionate and sodium valerate as 3HV-precursors for the synthesis of novel compositions of P(3HB-co-3HV-co-3HHx) terpolymers with interesting properties.  相似文献   

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