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Commercial palm oil-derived biodiesel fuels (palm BDFs) were thoroughly profiled based on the specifications of international fuel standards. Their main components were found to be fatty acid methyl esters (FAME) with different numbers of double bonds in the fatty acid tails in addition to small amounts of unreactive glycerides and impurities, the concentrations of which varied slightly among the regional producers in Thailand. The fuel properties of the as-received commercial palm BDFs met international fuel standards; unfortunately, the fuel degraded significantly over time, presumably due to the presence of polyunsaturated fatty acid methyl esters (poly-FAME) and impurities. To prevent this degradation, the commercial palm BDFs were upgraded into partially hydrogenated fatty acid methyl esters with outstanding oxidation stability (H-FAME, a new type of biodiesel fuel enriched in monounsaturated fatty acid methyl esters (mono-FAME)) over supported Pd catalysts with metallic Pd nanoparticles as the catalytically active sites in a batch-type glass reactor under mild conditions (80 °C and 0.5 MPa H2). In the upgrading process, the unwanted component poly-FAME, which had low oxidation stability, was selectively converted into the target component, mono-FAME with high oxidation stability. Although the impurities in the commercial palm BDFs poisoned the supported Pd catalysts, particularly the sulfur species, the homemade mesoporous silica-supported Pd catalyst with a high Pd dispersion of 47% gave higher activity and tolerance to the impurities in the synthesis of palm H-FAMEs than the commercial alumina-supported Pd catalyst, which had a low Pd dispersion of 16%. In the accelerated oxidation stability test, the B20 fuels formulated by blending petro-diesel with the palm H-FAMEs with enhanced oxidation stability produced almost no deposits or sludges, whereas the fuels formulated by blending petro-diesel with commercial palm BDFs were seriously degraded and acidified, and formed deposits and sludges. Moreover, the palm H-FAMEs could be further purified by selective removal of the monoglycerides (MG) and steryl glucosides (SG) through wintering and adsorption posttreatments, and were determined to be a reliable BDF source with high safety and security for use in high blend fuels.

The catalytic conversion of methanol to hydrocarbons (MTH) of gasoline has been studied over the modification of HZSM-5 zeolite catalysts, which were prepared by different ratios of rice husk ash (RHA) addition. The catalysts were characterized by BET, XRD, XRF, NH3-TPD, FT-IR and SEM techniques. The dehydration of methanol over prepared catalysts was carried out in a fixed-bed reactor at 300 oC with a constant flow rate of methanol under 1 atm of N2. The liquid hydrocarbons product was analyzed by GC-MS. The analysis showed that the major product provided by RHA-HZSM-5 catalysts was aromatic hydrocarbon-rich. According to the experimental results, the methanol conversion to hydrocarbons has been found to be a function of RHA ratio. The aromatic product selectivity was increased but that of the acidity of catalyst was decreased with the increase of RHA ratio. The study indicated that the hydrocarbon product distribution of the catalysts treated by RHA significantly depended on the acidity of catalyst.

The continuous two-step catalytic hydrogenation of methanol to hydrocarbons (MTH) was investigated for improving the distribution of liquid hydrocarbon products using HZSM-5 zeolite and consecutively with two supported Co catalysts, Co/Al2O3 and Co/SBA-15. The sequential catalytic system was employed to enhance the selectivity of long chain hydrocarbons. The catalysts were characterized by BET, XRD, XRF, NH3-TPD, and SEM techniques. The catalytic performance of prepared catalysts was performed at 300 oC in a fixed-bed reactor with the constant flow rate of methanol under 1 atm of N2. The liquid hydrocarbons were analyzed by GC-MS. The aromatic and light hydrocarbon products were produced by the HZSM-5 and Co-based catalysts. According to the analysis result, the aromatic hydrocarbon products of the catalysts modified by two-step of catalytic reaction have been significantly increased. The results indicated that the series of HZSM-5 and two supported Co catalysts system led to produce high yield of aromatic hydrocarbon products in the catalytic performance of methanol to hydrocarbon process comparing with only the single HZSM-5 catalyst.

Converting ethylene to biojet fuel range hydrocarbons via oligomerization is an important step in biojet production from ethanol. The present study investigates the catalytic ethylene oligomerization over platelet Ni-AlSBA-15 mesoporous catalysts. The catalysts are synthesized and characterized using nitrogen adsorption–desorption isotherms, X-ray fluorescence and X-ray diffraction techniques. The catalytic performances are then evaluated in a continuous flow fixed-bed reactor under various conditions of reaction weight hourly space velocities (0.56–4.5 h−1), temperatures (150–350 °C) and pressures (1–20 bar). Experimental results demonstrate that platelet Ni-AlSBA-15 is a promising catalyst for the ethylene oligomerization to produce biojet fuel range hydrocarbons. It performs a good catalytic activity, yielding 98–99 mol% ethylene conversion and 34–42 wt% C8+ selectivity at 0.56 h−1, 275–300 °C and 20 bar. The obtained products contain mainly C4–C10 olefins with low aromatic compounds. Moreover, the catalyst exhibits good stability of the activity during long periods of operation.

Palm oil is considered as a potential feedstock for biofuel production in Thailand due to its property and availability. In recent years, there has been an increased attention on upgrading of palm oil to biofuels using various technologies. One of the most promising technologies is pyrolysis, in which palm oil is heated at the temperature in the range of 400 to 500 °C under oxygen-free atmosphere. In the present study, the uncoated catalyst and coated catalyst pyrolysis processes of palm oil for biofuel production in a continuous flow microchannel reactor were investigated with various catalyst types (MgO, Al2O3) at 400-500 °C, 2 ml/hr palm oil flow rate, and 0.1 g of catalysts. Liquid product yield, solid product yield and gaseous product yield were determined. The obtained results revealed that the high triglyceride conversion could be achieved at a short reaction time in microchannel reactor, which attributed to the enhancement of both heat and mass transfer. The pyrolysis liquid products composed of hydrocarbons, free fatty acids, and other oxygenated compounds which are the results of triglyceride cracking. Furthermore, product selectivity of palm oil pyrolysis depended on temperature and catalyst type.

The palm oil industry produces large amounts of biomass by-products, such as palm empty fruit bunch (EFB), mesocarp fiber (MF), and kernel shell (KS). The thermal behavior and decomposition of the oil palm biomass wastes have been studied by thermogravimetry/mass spectrometry (TG/MS) and pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS). The determination of biopolymer and inorganic composition facilitated the interpretation of the thermal decomposition results. It was established that the chemical compositions of KS and MF were similar, while EFB contained significantly higher amount of cellulose and potassium, and decomposed in a narrower temperature range. In addition to the thermogravimetric curves (TG and DTG), the product distribution of pyrolyzates also reflected the compositional differences. Py-GC/MS and TG/MS experiments showed that the increasing potassium content of the samples reduced the intensity of 4-hydroxy-5,6-dihydro-2H-pyran-2-one, which is formed via depolymerization and dehydration of xylan units. Consequently, these experiments proved that beside cellulose, the depolymerization of hemicellulose was also hindered, while the dehydration, fragmentation, and charring reactions were catalyzed by potassium. Additionally, the evolution of the characteristic cellulose and lignin products shifted to lower temperatures. The most dominant aromatic pyrolysis product was phenol from each sample, which formed to a large extent from the abundant 4-hydroxybenzoate (4Hb) lignin subunits by scission and decarboxylation. KS also produced 4-hydroxybenzoic acid in significant amounts during pyrolysis at 450 °C confirming the presence of 4Hb subunits in lignin. The evolution of phenol started at 220 °C from the 4Hb moieties, and ended at about 600 °C from the residual phenolic units, while the release of guaiacol, vinylguaiacol, and syringol occurred between 300 and 450 °C as monitored by TG/MS. Some characteristic carbohydrate products were attributed to either hemicellulose or cellulose degradation based on the evolution profiles of KS and MF with separated carbohydrate decomposition steps. The comparison of the oil palm biomass wastes showed that EFB is supposed to be treated separately from KS and MF during the utilization process due to the different thermal behavior and composition.

Partial hydrogenation of palm biodiesel fuel (BDF) over 0.5wt%Pd/SBA-15 and 0.5wt%Pd/Zr-SBA-15 catalysts was examined by using a continuous fixed-bed reactor at 100 °C and 0.3 MPa under an atmosphere of H 2 , in comparison to the commercial 0.5wt%Pd/γ-Al 2 O 3 catalyst. The results showed that the 0.5wt%Pd/SBA-15 catalyst with high Pd dispersion and fast molecular diffusion through the short channeling pores gave the highest activity and selectivity in partial hydrogenation of polyunsaturated fatty acid methyl esters (FAME) as unstable components of palm BDF into cis -mono-unsaturated FAME as a target component of upgraded palm BDF with excellent oxidation stability and cold flow properties, which makes the addition of antioxidants unnecessary. By contrast, the 0.5wt%Pd/Zr-SBA-15 catalyst with strongly and moderately acidic sites gave low selectivity toward cis -mono-unsaturated FAME. The commercial 0.5wt%Pd/γ-Al 2 O 3 catalyst displayed much lower polyunsaturated FAME conversion and cis -mono-unsaturated FAME selectivity, associated with poor Pd dispersion and slow molecular diffusion through the disordered pores.

Facile synthesis of superficial Pd nanoparticles supported on carbonaceous SBA-15 (denoted as Pd/@SBA-15) as a new hydrotreating catalyst with enhanced activity and sulfur tolerance was accomplished for the production of partially hydrogenated fatty acid methyl esters (H-FAME), a high-quality biodiesel fuel enriched in monosaturated fatty acid methyl esters (mono-FAME) that can be used in high blends. Characterization, especially high-resolution electron microscopes and temperature-programmed techniques, indicated that the Pd nanoparticles (∼7 nm) formed spontaneously at the superficial area of carbonaceous SBA-15 with a hydrophobic surface and low acidity. In the synthesis of H-FAME using commercial palm oil-derived biodiesel fuel as a feedstock under mild conditions (

This research investigated the production of Fatty Acid Ethyl Ester (FAEE) from refined palm oil with ethyl acetate at supercritical conditions in a microreactor, which produced triacetin as the by-product instead of glycerol. The experiments were carried out in a microreactor at the reaction temperature in the range of 330 °C to 370 °C, with a pressure of 200 bar and an oil to ethyl acetate molar ratio of 1:50. Results showed that the residence time and temperature had a positive effect on FAEE and biodiesel yield, with the high FAEE yield of 63.6% and biodiesel yield of 78.3%.

This work reports on the preliminary results of using several acidic and basic solids, such as ZrO2, ZnO, SO42−/SnO2, SO42−/ZrO2, KNO3/KL zeolite and KNO3/ZrO2 as heterogeneous catalysts for crude palm kernel oil (PKO) and crude coconut oil (CCO) transesterification with methanol. It was found that ZnO and SO42−/ZrO2 exhibited the highest activity for both PKO and CCO transesterification. In the case of SO42−/ZrO2, only 1 wt.% of this acidic solid was needed to catalyze the reaction, and resulted in fatty acid methyl esters content higher than 90%. Moreover, a study of the catalyst's recyclability indicated that the spent SO42−/ZrO cannot be directly reused for the transesterification. However, this spent catalyst can be easily regenerated and the same activity can be obtained.