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Potential of advanced microporous zeolites and mesoporous materials derived from natural precursors as supports for iron phosphide catalysts in bio-jet fuel production from palm oil (Elaeis guineensis)
(2025-06-10)
Tanwongwan, Worapak
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Sartsamai, Ruttasart
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Kaewmeesri, Rungnapa
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Faungnawakij, Kajornsak
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Chollacoop, Nuwong
Iron phosphide (FeP) has emerged as an efficient catalyst for converting palm oil, a biomass-derived feedstock, into bio-jet fuel through the hydrocracking process. The catalytic performance of FeP is strongly influenced by the choice of support material. In this study, microporous MWW-type zeolites (MCM-22 and MCM-36) and mesoporous materials (MCM-41 and MCM-48) were successfully synthesized from entirely natural precursors, silica derived from rice husk and aluminosilicate gel extracted from kaolin clay, via a hydrothermal method, and employed as supports for FeP catalysts. Among these materials, MCM-22 zeolite exhibited the highest microporosity, followed by zeolite MCM-36, resulting in superior acidity compared to the mesoporous materials, MCM-41 and MCM-48. FeP supported on MCM-22 (FeP/MCM-22) demonstrated the best catalytic performance, liquid hydrocarbon yield (∼33%), and bio-jet selectivity (∼78%) were obtained, outperforming FeP/MCM-36, FeP/MCM-41, and FeP/MCM-48. This is due to its high surface area of micropores (∼187 m2 g−1) and the excellent acidity of this zeolite, which helped prevent FeP overloading and promote uniform metal distribution. Furthermore, it exhibited remarkable stability and reusability, with performance improving over three consecutive reaction cycles, LHCs yield increasing to 50% and bio-jet selectivity stabilizing at about 83%, attributed to enhanced acidity accessibility and progressive formation of the FeP active phase.
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NiO-YSZ anode composite material derived from mechano-chemical for solid oxide fuel cells application
(2025-06-01)
Srisuwan, Thanakorn
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Puengjinda, Pramote
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Kaewtrakulchai, Napat
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Chanpee, Sirayu
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Jadsadajerm, Supachai
This study investigates the effects of calcination time, milling duration, and sintering temperature on the properties of Nickel oxide and Yttria-stabilized zirconia (NiO-YSZ) anode composite materials for solid oxide fuel cell (SOFC) applications. NiO nanoparticles were synthesized from nickel (II) sulfate (Ni(II)SO<inf>4</inf>), with X-ray diffraction (XRD) confirming a face-centered cubic (FCC) structure. The crystallite size (21 nm) was achieved after 8 hours of calcination, while prolonged durations caused particle agglomeration. Ball-milling for 12 hours produced comparatively fine particles with an average of 706 nm, though extended milling led to grain growth and aggregation. Scanning electron microscopy (SEM) revealed nano aggregation. Sintering at 1200 °C improved the densification of the NiO-YSZ layer while increasing its porosity, which enhanced the reduction of NiO to metallic nickel (Ni). Electrochemical Impedance Spectroscopy (EIS) demonstrated lower impedance and improved electrochemical performance for cells cold-sintered at 1200 °C. These findings show the importance of optimizing processing conditions to enhance the performance of NiO-YSZ anode for SOFCs, offering valuable insights for advanced energy conversion technologies.
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Effects of synthetic conditions on the Pd particle sizes of Pd/SBA-15 catalysts and their performance for the partial hydrogenation of biodiesel fuels
(2024-07-01)
Supabunnapong, Thanadon
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Rungsi, Artita Na
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Luengnaruemitchai, Apanee
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Chen, Shih Yuan
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Mochizuki, Takehisa
Mesoporous silica (SBA-15)-supported Pd catalysts (Pd/SBA-15) with Pd particles of various sizes (4–17 nm) were obtained under different calcination conditions. These purpose-made Pd/SBA-15 catalysts are applied in the partial hydrogenation of soybean-oil-derived biodiesel fuel, rich in polyunsaturated fatty acid methyl esters (poly-FAME), to produce partially hydrogenated fatty acid methyl esters (H-FAME), rich in monounsaturated fatty acid methyl esters (mono-FAME), under mild conditions (80 °C, 0.5 MPa H<inf>2</inf>). The Pd particle size was strongly correlated with hydrogenation rate and selectivity, thereby influencing the composition and fuel properties of H-FAME. The Pd/SBA-15 catalyst with a Pd particle size of approximately 4 nm obtained by calcination at 300 °C in O<inf>2</inf> showed the highest initial hydrogenation rate and mono-FAME selectivity. The resulting H-FAME product was rich in mono-FAME and thus exhibited high oxidative stability and cold-flow properties compliant with high-blend biofuel standards. In contrast, the analog catalysts with Pd particle sizes ranging from 8 to 17 nm obtained by calcination at 300 °C in air and nitrogen and at 500 °C featured lower hydrogenation rates and afforded larger amounts of undesired saturated fatty acid methyl esters. These findings shed light on the effect of the Pd particle size on the hydrogenation of biodiesel and can be readily applied to the hydrogenation of other biofuels.
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Bimetallic PdNi catalyst on cattail Leaves-Derived nanoporous carbon support for synthesis of partially hydrogenated fatty acid methyl ester (H-FAME)
(2024-06-01)
Longprang, Tripob
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Kaewtrakulchai, Napat
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Kiatkittipong, Worapon
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Srifa, Atthapon
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Chollacoop, Nuwong
Cattail leaves (CL) have been used as a carbon source to synthesize nanoporous carbon (NPC) support with high surface area (S<inf>BET</inf> = 2002.12 m2g−1) via hydrothermal carbonization and potassium hydroxide (KOH) activation. The studied catalysts, including monometallic Pd/NPC and Ni/NPC, and bimetallic PdNi/NPC, were synthesized and characterized by using several techniques (e.g., scanning electron microscopy, transmission electron microscopy, nitrogen sorption, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction). Their catalytic activity toward partial hydrogenation of palm biodiesel to H-FAME was tested, and the liquid product composition, cloud point, and oxidation stability were determined. The studied catalysts have a high porosity with the S<inf>BET</inf> of approximately 2037.34–2187.96 m2g−1 led to excellent metal dispersion. Although Ni did not show high catalytic activity compared to Pd, Ni incorporated with Pd as PdNi/NPC catalyst significantly increased the cis-C18:1 selectivity and prevented the catalytic deactivation during the partial hydrogenation. The oxidation stability of palm biodiesel feedstock was increased from 13.69 to 17.12 h while the cloud points adversely increased by only 3 degrees from 12 to 15 °C (still lower than 16 °C of the Thai industrial recommendation) with bimetallic PdNi/NPC catalyst. The main benefit of bimetallic PdNi/NPC over monometallic Pd/NPC and Ni/NPC is shown through not only higher C18:2 conversion but also much higher cis-to-trans ratio of C18:1 resulting in higher oxidation stability with acceptable compromise on the cloud point increasing. Consequently, the produced palm H-FAME can be used at a high blend ratio.
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Effect of a retrofitted metallic microfiber partial flow diesel particulate filter on a light duty diesel vehicle particle emission characteristics
(2024-02-01)
Mon Phyo, Mi Zwe
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Phairote, Watanyoo
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Srilomsak, Mek
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Charoenphonphanich, Chinda
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Masomtob, Manop
This study was conducted two distinct experiments, using a light-duty diesel vehicle at various engine speeds and loads as well as the new European driving cycle (NEDC) comparing commercial diesel fuel (B7) and pure biodiesel (B100). The NEDC involves a combination of urban and extra urban driving conditions. It aims to study a diesel vehicle's thermal efficiency as well as its gaseous and particulate matter (PM) emissions. This involves comparing results with and with no diesel oxidative catalyst (DOC) and a partial flow diesel particulate filter (PDPF) system. The surface morphology, micro- and nanostructure of a diesel vehicle's PM were also examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) to determine nanostructural and dimensional changes after mounting a DOC-PDPF system. Comparison of B7 and B100 combustion showed that B100 had around 1 % increase in brake thermal efficiency (BTE) at 1500 and 2000 rpm compared to B7 since B100 is a more oxygenated biofuel. At 2500 rpm, similar BTE values were observed. Introduction of a DOC-PDPF system resulted in an approximately 1 % BTE reduction for both fuels. This was due to greater friction losses caused by backpressure from the DOC-PDPF system. Increased exhaust backpressure was progressive, ranging from 1 kPa at idle speed to 6 kPa at high engine speeds for both tested fuels. The DOC-PDPF system respectively minimized PM emissions and particle numbers (PNs) by more than 50 % and 35 % for B7 and 71 % and 31 % for B100. These results are average values under the various phases of NEDC testing. A 30 % decrease in PM and a 44 % reduction in PNs under the overall test cycle were found when B100 was tested compared to B7. The soot primary particle size was reduced from 34.69 to 29.08 nm and the carbon fringe length diminished from 1.25 to 0.949 nm at different pre- and post-DOC-PDPF locations. This was due to partial oxidation on the surfaces of the PDPF metallic microstructure. PM undergoes simultaneous partial oxidation after passing through the DOC-PDPF system, as confirmed by TGA analysis.
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Combination of natural silica and alumina sources for synthesis of MCM-22 zeolite
(2023-08-01)
Tanwongwan, Worapak
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Chollacoop, Nuwong
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Faungnawakij, Kajornsak
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Assabumrungrat, Suttichai
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Nakhanivej, Puritut
Zeolite has become a promising material that can potentially play a pivotal role in resolving environmental crises. Among zeolite families, MCM-22 zeolite shows outstanding intrinsic properties associated with the topology and porous structure, offering ion-exchange advantages for catalytic activity processes. The synthesis of MCM-22 zeolite becomes challenging when concerning the cost and catalytic performance. To overcome this bottleneck, we demonstrate a sustainable route of a hydrothermal process using natural resources as starting materials. Rice husk from agricultural waste was used as a silica source while natural clays (kaolin and bentonite) were applied as alumina sources. The products from natural sources were compared with the use of commercial starting materials, e.g., NaAlO<inf>2</inf> (for alumina) and Na<inf>2</inf>SiO<inf>3</inf> and TEOS (for silica), in points of crystal, compositional, and morphological views. We showed that the high purity of MCM-22 zeolite can be obtained from rice husk silica (RHS) and aluminosilicate gel (ASG) extracted from kaolin, while the use of ASG extracted from bentonite tended to be unsuitable to generate the zeolite formation. We also studied the effects of reaction time and the ratio of RHS/ASG on the crystallinity and surface area of MCM-22. The architecture and acidity of an optimal product were explored by Nuclear magnetic resonance spectroscopy and Temperature-programmed desorption of ammonia, demonstrating the success of achieving well acidity.
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Physicochemical characteristics of ashes deposited on a wall flow diesel particulate filter of compression ignition engine
(2023-06-01)
Rodvanna, Sattatad
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Srilomsak, Mek
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Nuthong, Chaiwat
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Charoenphanich, Chinda
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Masomtob, Manop
The investigation of physicochemical characteristics of metal oxide ashes, deposited on a diesel particulate filter, was conducted using electron microscopy, energy dispersive spectroscopy, X-Ray fluorescence, and X-Ray diffractometry techniques. Iron is the main component of deposited ash on the DPF, and other ash components consisted of elements such as silicon, calcium, copper, sulfur, phosphorus, zinc, aluminum and minor chromium. It was clarified that this metal oxide ash has catalytic effect that contributed to an enhancement of soot oxidation. The apparent activation energies of soot oxidation on SiC powder and metal oxide ashes powder are approximately 169 and 135 kJ/mol, respectively.
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Influence of ethanol-biodiesel blends on diesel engines combustion behavior and particulate matter physicochemical characteristics
(2022-12-01)
Karin, Preechar
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Tripatara, Aphichai
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Wai, Phyo
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Oh, Ban Seok
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Charoenphonphanich, Chinda
Ethanol-blended biodiesel fuel can reduce smoke emissions by over 50% on both a single-cylinder engine and a four-cylinder engine. The average single primary particle size of biodiesel blended diesel, biodiesel, and ethanol blended biodiesel soot are approximately 30, 27, and 29 nm, respectively. The maximum graphene fringe length of biodiesel blended diesel, biodiesel, and ethanol blended biodiesel CI engine's soot are approximately 5.2, 4.6, and 4.5 nm. The carbon atom density of soot particles emitted from the diesel, biodiesel, and ethanol blended biodiesel CI engines are approximately 102, 91, and 88 atoms/nm3.
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Experimental investigation of the influence of ethanol and biodiesel on common rail direct injection diesel Engine's combustion and emission characteristics
(2022-11-01)
Wai, Phyo
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Kanokkhanarat, Phobkrit
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Oh, Ban Seok
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Wongpattharaworakul, Veerayut
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Depaiwa, Nattawoot
This study aims to characterize the effect of oxygenated biofuels in diesel engine combustion, thermal efficiency, and emission by blending different percentages of ethanol and biodiesel with fossil fuel derived diesel. In this research, 5% and 10% by weight of bioethanol were added to commercial B10 (10% biodiesel and 90% diesel), B20 (20% biodiesel and 80% diesel) and B100 (100% biodiesel) and experimented on using a 3 L four-cylinder common rail diesel engine. The experiment was performed under three engine speeds of 1000 rpm, 1500 rpm, and 2000 rpm with three constant engine torques of 56 Nm, 84 Nm, and 140 Nm. The results show that ethanol-biodiesel-diesel ternary blended fuels are higher in premixed combustion pressure and net heat release rate (NHRR) peaks. The cumulative heat release of ethanol blended fuels is also higher for ethanol blended fuels. The fuel consumption increased with the ethanol and biodiesel percentage in the blended fuels due to the lower heating value while the brake thermal efficiency did not decrease. It was clearly observed that the particle emission could be reduced by more than 50% when ethanol and biodiesel percentage increased.
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Preparation of Activated Carbon from Various Biomasses by Single-Stage Pyrolysis
(2022-02-04)
Thowphan, Suwimon
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Kaewtrakulchai, Napat
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Jaruvanawat, Anuchit
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Chutipaijit, Sutee
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Puengjinda, Pramote
Nowadays, activated carbon were successfully synthesized from biomass, Activated nanoporous carbon have been widely for several applications such as solution to air pollution, solution to water pollution. In this work, study the effects of pyrolysis temperature of activated carbon synthesized from coconut shell, coconut leaves, coconut bracts, cattail flower, cattail leaves, mangosteen bracts, durian bracts, corn leaves, eucalyptus bracts, sugarcane leaves and toddy palm bracts. The pyrolysis of various biomass was studied at the temperature of 700-900 °C for 2 h under N2 flow of 100 ml/min. The results showed that biomass types and pyrolysis temperature affects the structural and physicochemical properties of activated carbon such as pore structures, surface functional groups and elemental compositions. activated carbon obtained at 800 °C for 2 h had the highest composed of amorphous phase, porosity and surface area.

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