KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 29

Some of the metrics are blocked by your
consent settings
Coconut Residue-Derived Nanoporous Carbon via Hydrothermal Carbonization for Nanoporous Carbon-Based Supercapacitor Electrodes
(2025-07-01)
Ruenroengrit, Kemchat
;
Kunyuan, Jumpon
;
Ruttanadech, Nuttapong
;
Kaewtrakulchai, Napat
;
Puengjinda, Pramote
The increasing demand for sustainable and cost-effective energy storage solutions has driven interest in biomass-derived carbon materials for supercapacitor electrodes. This study explores the valorization of coconut residue (CR), an abundant agricultural waste, as a carbon precursor for nanoporous carbon (NPC) production. NPC was synthesized via hydrothermal carbonization (HTC) of CR, followed by chemical activation using potassium hydroxide (KOH) at varying temperatures (700, 800, and 900 °C). The effects of activation temperature on the structure and electrochemical performance of the NPC were systematically investigated. The activated materials exhibited amorphous, highly porous structures, with surface areas increasing alongside activation temperature—reaching a maximum of 1969 m2 g−1 at 900 °C. Electrochemical characterization was conducted using a three-electrode setup through cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) in a 1 M Na<inf>2</inf>SO<inf>4</inf> electrolyte. The sample activated at 900 °C with a CR:KOH weight ratio of 1:2.5 achieved the highest specific capacitance of 52 F g−1 at a specific current of 1 A g−1. These findings underscore the potential of CR as a low-cost and sustainable raw material for fabricating efficient electrode materials in energy storage applications.
Some of the metrics are blocked by your
consent settings
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
;
Sartsamai, Ruttasart
;
Kaewmeesri, Rungnapa
;
Faungnawakij, Kajornsak
;
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.
Some of the metrics are blocked by your
consent settings
NiO-YSZ anode composite material derived from mechano-chemical for solid oxide fuel cells application
(2025-06-01)
Srisuwan, Thanakorn
;
Puengjinda, Pramote
;
Kaewtrakulchai, Napat
;
Chanpee, Sirayu
;
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.
Some of the metrics are blocked by your
consent settings
Nanoporous Carbon-Supported Bimetallic (Ni, Cu, and Fe)-Mo Catalysts for Partial Hydrogenation of Biodiesel
(2024-10-15)
Jaruwat, Dolrudee
;
Kaewtrakulchai, Napat
;
Siriorarnroj, Siwat
;
Srifa, Atthapon
;
Kiatkittipong, Worapon
Upgrading biodiesel or hydrogenated fatty acid methyl esters (H-FAMEs) by partial hydrogenation is a second-generation biofuel with high specific fuel characteristics, such as superior cold flow properties, higher oxidative stability, and lower hazardous gas emissions, allowing this biofuel to provide excellent fuel properties, over conventional biodiesel. This study assessed the potential of using nanoporous carbon produced from cattail leaves (CL) as an alternative catalyst support. We synthesized various catalysts including monometallic Mo/NPC, Ni/NPC, Ce/NPC, and Fe/NPC catalysts, as well as bimetallic molybdenum-based catalysts doped with nickel, copper, or iron for the partial hydrogenation of soybean biodiesel. The NPC support demonstrated a surface area (S<inf>BET</inf>) of approximately 1,323 m2g-1, which greatly increases the catalytic activity through the efficient dispersion of catalyst active sites. The partial hydrogenation reaction of soybean FAME over the MoNi/NPC catalyst obtained the highest catalytic activity with enhanced oxidation stability from 3 to 14 h, and the cloud point and pour point increased from 2 to 13 °C and −1 to 10 °C, respectively. Hence, the selection of catalysts is crucial due to their impact on the feasibility of the process and its economic viability. This article focuses on highlighting the effectiveness of a highly promising catalyst for partial hydrogenation as well as examining the variables that influence the primary reaction pathway.
Some of the metrics are blocked by your
consent settings
Valorization of horse manure conversion to magnetic carbon nanofiber for dye adsorption by hydrothermal treatment coupled with carbonization
(2024-06-01)
Kaewtrakulchai, Napat
;
Chanpee, Sirayu
;
Pasee, Warit
;
Putta, Ampol
;
Chutipaijit, Sutee
Pollution of water resources has recently increased as a result of expanded industrial activity. Recycling waste biomass into bio-adsorbent material offers a cheap, easy, and eco-friendly solution. In this study, magnetic carbon nanofibers (MCNF) with a highly porous structure were developed from magnetite-preloaded horse manure by hydrothermal treatment followed by carbonization using different ratios of iron (III) nitrate and iron oxide as magnetic precursors. The produced MCNF had a very porous structure with specific surface area of 435.31 m2/g and high carbon content. The magnetic characteristics of MCNF promoted by the presence of iron oxide species. The saturated magnetization of MCNF obtained from a 5:5 ratio of the magnetic precursors (iron (III) nitrate: iron oxide) was 2.48 emu/g. Synthesized MCNF was applied as a bio-adsorbent for methylene blue (MB) removal from aqueous solution, with results showing excellent dye adsorption of 92–99 %. MB adsorption was facilitated by pore filling, electrostatic contact, hydrogen bonding, and ion complexation. Experimental results indicated that the Freundlich isotherm and pseudo-second-order kinetic models concurred with the observed MB adsorption data, suggesting that the adsorption mechanism involved multilayered micropore interactions between magnetite and MB chemisorption. The resulting magnetic adsorbent was successfully removed from the aqueous solution by physical separation. Findings indicated that horse manure-derived MCNF could be used as an efficient bio-adsorbent to remove organic contaminants in wastewater.
Some of the metrics are blocked by your
consent settings
Cattail (Typha angustifolia) flower-derived porous carbons as support of electroplated Ni and Cu catalysts for hydrogenation of methyl levulinate to γ-valerolactone
(2023-09-01)
Kaewtrakulchai, Napat
;
Gunpum, Wachiraporn
;
Fuji, Masayoshi
;
Eiad-Ua, Apiluck
The novel synthesis of carbon-supported metal catalysts was completely developed by using electroplating technique. A carbon support was prepared from cattail (Typha angustifolia) flowers (CF) as a bio-material precursor through a hydrothermal process combined carbonization. The prepared carbons exhibited a high surface area, porosity, and excellent electrical conductivity, which is relevant characteristics to materials utilized for metal catalyst supporter. In this study, electroplating technique has been applied for the catalyst synthesis to utilize in hydrogenation of methyl levulinate to γ-valerolactone. Interesting experimental parameters in electroplating such as metal precursors (Ni and Cu), solution temperatures (40, 45, 50, 55, and 60 °C), and applied voltages (3.0, 3.5. 4.0, 4.5, and 5.0 V) were thoroughly investigated on some characteristics of catalysts. The physicochemical properties of studied catalysts were comprehensively characterized by using high-resolution scanning electron microscopy (HRSEM) equipped with energy dispersive spectroscopy (EDS) and focused ion beam (FIB), X-ray diffraction (XRD), and nitrogen sorption analyzer to examine surface morphology, elemental compositions, distribution of the metal in cross-section surface, crystallinity, and textural pore characteristic, respectively. In electroplating process, the solution temperature of 50 °C with the applied voltage of 4 V become an optimal condition for the synthesis of catalyst with uniformed metallic phase and high metal dispersion on carbon support. Ni-carbon and Cu-carbon catalysts exhibited an excellent catalytic activity with the methyl levulinate conversion of 32.68% and 29.17%, respectively.
Some of the metrics are blocked by your
consent settings
Porous Biochar Supported Transition Metal Phosphide Catalysts for Hydrocracking of Palm Oil to Bio-Jet Fuel
(2022-10-01)
Kaewtrakulchai, Napat
;
Smuthkochorn, Araya
;
Manatura, Kanit
;
Panomsuwan, Gasidit
;
Fuji, Masayoshi
The upgrading of plant-based oils to liquid transportation fuels through the hydrotreating process has become the most attractive and promising technical pathway for producing biofuels. This work produced bio-jet fuel (C<inf>9</inf>–C<inf>14</inf> hydrocarbons) from palm olein oil through hydrocracking over varied metal phosphide supported on porous biochar catalysts. Relative metal phosphide catalysts were investigated for the highest performance for bio-jet fuel production. The palm oil’s fiber-derived porous biochar (PFC) revealed its high potential as a catalyst supporter. A series of PFC-supported cobalt, nickel, iron, and molybdenum metal phosphides (Co-P/PFC, Ni-P/PFC, Fe-P/PFC, and Mo-P/PFC) catalysts with a metal-loading content of 10 wt.% were synthesized by wet-impregnation and a reduction process. The performance of the prepared catalysts was tested for palm oil hydrocracking in a trickle-bed continuous flow reactor under fixed conditions; a reaction temperature of 420 °C, LHSV of 1 h−1, and H<inf>2</inf> pressure of 50 bar was found. The Fe-P/PFC catalyst represented the highest hydrocracking performance based on 100% conversion with 94.6% bio-jet selectivity due to its higher active phase dispersion along with high acidity, which is higher than other synthesized catalysts. Moreover, the Fe-P/PFC catalyst was found to be the most selective to C<inf>9</inf> (35.4%) and C<inf>10</inf> (37.6%) hydrocarbons.
Some of the metrics are blocked by your
consent settings
Catalytic deoxygenation of palm oil over metal phosphides supported on palm fiber waste derived activated biochar for producing green diesel fuel
(2022-09-13)
Kaewtrakulchai, Napat
;
Fuji, Masayoshi
;
Eiad-Ua, Apiluck
Palm oil conversion into green diesel by catalytic deoxygenation (DO) is one of the distinctive research topics in biorefinery towards a bio-circular-green economic model to reduce the greenhouse gas emissions. In this study, palm fiber waste was explored as an alternative precursor for the preparation of activated biochar as a support material. A new series of nickel phosphide (Ni-P) and iron phosphide (Fe-P) catalysts supported on palm fiber activated biochar (PFAC) was synthesized by wetness impregnation, and extensive characterization was performed by several techniques to understand the characteristics of the supported metal phosphide catalysts prior to palm oil deoxygenation for producing of green diesel (C<inf>15</inf>-C<inf>18</inf> hydrocarbons). The PFAC support exhibited suitable physicochemical properties for catalyst preparation, such as high carbon content, and high porosity (S<inf>BET</inf> of 1039.64 m2 g−1 with V<inf>T</inf> of 0.572 cm3 g−1). The high porosity of the catalyst support (PFAC) significantly promotes the metal phosphide nanoparticle dispersion. The DO of palm oil was tested in a trickle bed down flow reactor under hydrogen atmosphere. The outstanding catalytic performance of supported Ni-P and Fe-P catalysts provided an impressive liquid hydrocarbon yield between 63.37 and 79.65% with the highest green diesel selectivity of 62.64%. Decarbonylation (DCO) and decarboxylation (DCO<inf>2</inf>) are the main pathways for the relative phosphide catalysts as presented by the high number of C<inf>n−1</inf> atoms (C<inf>15</inf> and C<inf>17</inf> hydrocarbons). In addition, metal phosphide/PFAC catalysts could achieve great potential application as a promising alternative catalyst for biofuel production via deoxygenation for large-scale operation owing to their excellent catalytic activity, simple preparation, and utilization of sustainable resources.
Some of the metrics are blocked by your
consent settings
Nanoporous Carbon from Water Hyacinth via Hydrothermal Carbonization assisted Chemical Activation for Dye adsorption
(2022-07-01)
Sukulbrahman, Manu
;
Siraorarnroj, Siwat
;
Suksai, Nattaya
;
Kaewtrakulchai, Napat
;
Chutipaijit, Sutee
Nanoporous carbon was successfully prepared by hydrothermal carbonization with chemical activation using water hyacinth as a raw material. The porous carbon was produced for the adsorption of methylene blue (MB), which is an organic pollutant in wastewater from several industries. The effect of various parameters such as pH, dye concentration and adsorption period time on dye removal were studied. The highest removal efficiency of MB obtained using WH nanoporous carbon was approximately 96.8-99.9% within an adsorption time between 10 and 30 min. The dye removal capacity increased with increasing of period time during the adsorption test. Moreover, the adsorption kinetics of MB during adsorption process was explained by the Langmuir and Freundlich adsorption isotherms.
Some of the metrics are blocked by your
consent settings
High performance nanoporous carbon from mulberry leaves (Morus alba L.) residues via microwave treatment assisted hydrothermal-carbonization for methyl orange adsorption: Kinetic, equilibrium and thermodynamic studies
(2022-03-01)
Siraorarnroj, Siwat
;
Kaewtrakulchai, Napat
;
Fuji, Masayoshi
;
Eiad-ua, Apiluck
High performance nanoporous carbons were directly prepared from mulberry leaves (Morus alba L.) residues by the hydrothermal-carbonization with chemical reagent combined the microwave-assisted treatment. The as-purified ML porous carbon (MPC) was successfully applied for the adsorption of methyl orange, which is one of crucial waste-water pollutants left from an industrial sector. The MPC sample obtained from the hydrothermal process (200 °C, 12 h) using an activation of 15 wt% NaOH (700 °C, 2 h), and combined with microwave treatment at 700 W for 6 min, specifically exhibited micropores and mesopores in the MPC morphological structure. Accordingly, the highest S<inf>BET</inf> was approximately 791.79 m2/g with the total pore volume of 0.495 cm3/g. Moreover, the adsorption performance test of MPC was conducted by the shaking unit using 100 ppm methyl orange concentration. The MPC showed the highest methyl orange-adsorption uptake of 99% at 30 °C under an ambient pressure (1 atm). The development of mulberry leaves (Morus alba L.) residues into porous carbon exhibited a great attention for dyes adsorption with a rapid adsorption kinetic, and excellent adsorption capacity, which are a promising-characteristics for practical waste-water adsorption experiments.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results