KMITL

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

Browse

Search Results

Now showing 1 - 10 of 14
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Optimization of hydrothermal carbonization of Rhizoclonium riparium macroalgae using response surface methodology for high-performance solid biofuel production
    (2026-01-01)
    Chanpee, Sirayu
    ;
    Jadsadajerm, Supachai
    ;
    Manatura, Kanit
    ;
    Wongrerkdee, Sutthipoj
    ;
    Eiad-ua, Apiluck
    Hydrothermal carbonization (HTC) was adopted as a promising approach for improving fuel quality for several high-moist biomass. In this study, the Rhizoclonium riparium macroalgae (RMA), an abundant marine alga in an aquaculture pond, was successfully converted into hydrochars as a sustainable solid biofuel. The Box Behnken design (BBD) was applied for the HTC experiment to investigate the individual and interactive effects of operating parameters, including HTC temperature, reaction time, and water ratio, on hydrochar physicochemical characteristics and fuel properties. The response surface optimization (RSM) revealed maximum mass yield (MY) of 79.1%, higher heating value (HHV) of 23.6 MJ/kg, and energy yield (EY) of 94.4%. The RSM-BBD of process parameters and their HTC effects showed that the decreasing MY and EY were significantly due to the HTC temperature and residence time. From ANOVA analysis, temperature, time, and water ratio were the most significant parameters responding to MY, HHV, and EY. The optimal conditions for hydrothermal carbonization (HTC) of RMA as a solid biofuel were determined to be a temperature of 200 °C, a duration of 2 h, and a water-to-biomass ratio of 1:1, producing the highest energy yield (EY) of 95.3%. Utilizing RSM-BBD to investigate HTC parameters for hydrochar production is a suitable effort for technical scalability.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Oil palm leaf-derived nanoporous carbon via hydrothermal carbonization combined with NaOH microwave activation for tetracycline adsorption
    (2025-11-01)
    Chanpee, Sirayu
    ;
    Apinyakul, Naruemon
    ;
    Kaewtrakulchai, Napat
    ;
    Khemasiri, Narathon
    ;
    Eiad-ua, Apiluck
    Generally, the increase in pharmaceutical industrial activities has led to a corresponding rise in water resource contamination. Efforts have been dedicated to addressing the urgent challenge of waste biomass disposal by developing recycling methods capable of producing bio-adsorbents. Adsorption is a promising approach for removing tetracycline contaminants, owing to its simplicity, stability, and cost-effectiveness. In this study, a low-cost activated biochar was successfully developed using oil palm leaf (OPL) via hydrothermal carbonization (HTC) combined microwave-assisted pyrolysis system (MAPS) using sodium hydroxide (NaOH). The HTC and MAPS processes enhanced high mass yield, porosity, energy efficiency, and reduced reaction time. NaOH treatment improved the porosity of the activated biochar derived from OPL, resulting primarily in a mesoporous structure. However, NaOH treatment via the MAPS process increased surface area and porosity. Among the samples tested, OPLC-NaOH-1:1 exhibited the largest surface area and highest porosity, making it the chosen candidate for further TC adsorption tests. The adsorption experiments revealed that the Langmuir isotherm model and the pseudo-second-order kinetic model accurately matched the experimental data, suggesting a mono-layered adsorption mechanism due to micropores and chemisorption interactions. Additionally, thermodynamic analysis indicated an endothermic and spontaneous reaction during the adsorption process. The adsorption of nanoporous carbon for TC was primarily regulated by pore filling, hydrogen bonding, electrostatic effects, and π-π interactions also playing a significant role. Overall, this study highlights the potential of utilizing OPL waste as a sustainable material for producing nanoporous carbon and underscores the effectiveness of nanoporous carbon for adsorbing antibiotics.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    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 
    Item type:Publication,
    Physicochemical properties and hydrophobicity enhancement of water-washed durian peel by oxidative torrefaction at 250 °C
    (2025-01-01)
    Kaewtrakulchai, Napat
    ;
    Soukaew, Nuttawan
    ;
    Phongaksorn, Monrudee
    ;
    Wisetsai, Awat
    ;
    Pimsamarn, Jindarat
    Durian peel presents disposal challenges but offers potential as a renewable biofuel feedstock. However, high ash content, hygroscopicity, and low energy density limit its direct application. This study examined the effects of oxidative torrefaction at 250 °C (0–21 vol% O₂) combined with water washing pre-treatment on the physicochemical and hydrophobic properties of durian peel. Fuel quality was evaluated by proximate and ultimate analyses, HHV, EMC, water contact angle, FTIR, and SEM. Water washing reduced ash content by ~80%. Increasing oxygen concentration promoted devolatilization and carbonisation, with carbon content rising above 55 wt% and HHV reaching 22.34 MJ/kg. The lowest EMC (7.25%) and hydrophobic stability were obtained for washed samples at 5 vol% O₂. SEM revealed porous carbon-rich structures, while FTIR confirmed the removal of hydrophilic groups. The combined method improved energy density, minimised ash, and significantly enhanced hydrophobicity, producing coal-like biofuel suitable for storage, transportation, and co-firing applications.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Co-hydrothermal carbonization of polystyrene waste and maize stover combined with KOH activation to develop nanoporous carbon as catalyst support for catalytic hydrotreating of palm oil
    (2024-12-01)
    Kaewtrakulchai, Napat
    ;
    Chanpee, Sirayu
    ;
    Jadsadajerm, Supachai
    ;
    Wongrerkdee, Sutthipoj
    ;
    Manatura, Kanit
    Plastic waste is massively generated daily from households, mainly as packaging material, causing serious surrounding ecological problems. The development of plastic waste for higher value-added applications instead of landfilling and incineration has received consideration interest in bioenergy and material science research. Herein, a nanoporous carbon support of nickel phosphide catalyst for palm oil hydrotreating was developed from blended polystyrene waste and maize stover via the Co-hydrothermal carbonization (HTC) coupled with the KOH activation process. The Co-HTC parameters, such as temperature, reaction time, and PS percentage, were studied on the properties of co-hydrochar feedstocks for further activation using the Box behnken design. From the comprehensive characterization results, response surface methodology (RSM) results showed that the rising polystyrene proportion significantly exhibited the higher production yield and fixed carbon of co-hydrochar products, an essential characteristic for porous carbon manufacturing. After activation step, the final nanoporous carbon derived from the co-hydrochar (PMPC) exhibited the highest specific surface area of 1033.58 m<sup>2</sup>/g with total pore volume of 0.45 cm<sup>3</sup>/g. Moreover, the PCMC-supported nickel phosphide catalysts were successfully synthesized and tested for the catalytic hydrotreating of palm oil as alternative catalyst. The NiP-PMPC catalyst represents an impressive liquid hydrocarbon yield of 74.68 % with a high green diesel selectivity of 85.92 % at 100 % palm oil conversion. The findings of this study might help develop and utilize blended plastic waste and agricultural waste as an alternate catalytic support for various processes in biofuel and biochemical synthesis.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Solid shrimp waste derived nanoporous carbon as an alternative bio-sorbent for oxytetracycline removal from aquaculture wastewater
    (2024-06-15)
    Kaewtrakulchai, Napat
    ;
    Samattakarn, Nippit
    ;
    Chanpee, Sirayu
    ;
    Assawasaengrat, Pornsawan
    ;
    Manatura, Kanit
    Recently, it has been critical to effectively remove oxytetracycline (OTC) from aquaculture wastewater before releasing into the environment. The adsorption process is recognized as an efficient pathway for removing OTC since it is a simple, stable, and cost-effective method. This study aims to develop nanoporous carbon entirely from shrimp waste (SW) via hydrothermal carbonization assisted with KOH activation. Existing KOH significantly increases the porosity of SW nanoporous carbon. The optimal SW porous carbon was obtained using 5 wt%KOH for activation, which had the largest surface area of 679.51 m<sup>2</sup>/g with the total pore volume of 0.458 cm<sup>3</sup>/g. Moreover, the SW porous carbon with the highest porosity was selected for the OTC adsorption. The Langmuir isotherm model and the pseudo-second-order kinetic model match the experimental data, implying that the adsorption mechanism is mono-layered adsorption due to micropores by chemisorption interaction. The adsorption capacity significantly improved by increasing the dosage of SW nanoporous carbon. The SW nanoporous carbon adsorption for OTC is primarily regulated by pore filling affected by hydrogen bonding, and π-π* interaction also plays a significant role. The SW nanoporous carbon showed an efficient OTC adsorption after 5 regeneration cycles. This work demonstrates biomass waste recycling and emphasizes the potential of aquatic food processing waste-derived nanoporous carbon for antibiotic adsorption.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    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 m<sup>2</sup>/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 
    Item type:Publication,
    Synthesis of nanoporous carbon from brewer waste by hydrothermal carbonization assisted chemical activation for carbamazepine adsorption
    (2024-06-01)
    Apinyakul, Naruemon
    ;
    Chanpee, Sirayu
    ;
    Kaewtrakulchai, Napat
    ;
    Khemasiri, Narathon
    ;
    Eiad-ua, Apiluck
    Nanoporous carbon (NPC) has gained significant attention in wastewater treatment due to its effectiveness. The adsorption process, known for its simplicity, stability, and cost-effectiveness, is widely recognized as an efficient method for removing carbamazepine (CBZ) residues accumulate in the environment. However, the application of NPC is often hindered by challenges in the regeneration process after use, as well as issues related to large surface area, pore size, and functional groups. Fortunately, the samples in this study not only maintained their adsorption efficiency but also demonstrated the ability to be regenerated multiple times. Herein brewery waste was subjected to hydrothermal treatment at 200 °C for 1 h and followed by KOH and NaCl activation with different KOH:NaCl (w/w) ratios of 5:0, 4:1, 3:2, 1:1, 2:3, 1:4, and 0:5 to optimize the properties of malt husk derived nanoporous carbon (NPC). The optimal condition KOH:NaCl ratio of 1:1 had a maximum specific surface area of 906 m<sup>2</sup>/g with a total pore volume of 0.252 cm<sup>3</sup>/g. According to the adsorption test, the CBZ adsorption isotherm was well-fitted to the Langmuir model (R<sup>2</sup> = 0.976) kinetic data were consistent with the pseudo-second-order model (R<sup>2</sup> = 0.995). This suggests that the adsorption mechanism involves monolayer adsorption and chemisorption interaction. The Gibbs free energy and enthalpy of CBZ adsorption by NPC were found to be spontaneous and endothermic. The regeneration test revealed a 95.35% decrease in the adsorption capacity of NPC after 5 repeated cycles. Consequently, the study suggests a potential application of nanoporous carbon from MH as an alternative adsorbent for removing carbamazepine in wastewater.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Upgrading of Corn Stalk Residue and Tannery Waste into Sustainable Solid Biofuel via Conventional Hydrothermal Carbonization and Co-Hydrothermal Carbonization
    (2023-01-01)
    Kaewtrakulchai, Napat
    ;
    Chanpee, Sirayu
    ;
    Manatura, Kanit
    ;
    Eiad-Ua, Apiluck
    Hydrothermal carbonization (HTC) and co-hydrothermal carbonization (Co-HTC) are efficient thermochemical conversion processes for upgrading the fuel properties of biomass feedstocks. This study investigates the conversion of high moisture industrial waste, leather waste (LW), and agricultural residue, corn stalk (CS) into sustainable solid fuel via the HTC and Co-HTC. The impact of experimental variables, such as HTC temperature, residence time, and reaction pathway (i.e., HTC and Co-HTC process), on the physicochemical properties and fuel quality of hydrochar was also comprehensively explored. The highest heating value of hydrochar product, approximately 23.4 MJ/kg, was obtained from the Co-HTC condition of 280°C for 8 h. The mutual interaction between two biowastes exhibited superior synergistic fuel characteristics, including lower ash content, higher carbon percentage, and improved energy density. However, the remaining ash content of hydrochar decreased by approximately 25.01%-44.52%, produced from both HTC and Co-HTC processes. The hydrothermal treatment process improved the hygroscopic properties of hydrochar. Finding results show that the HTC and Co-HTC are the potential thermochemical conversions for producing sustainable solid fuel from several biowastes. In addition, the Co-HTC process showed a better hydrochar fuel quality.
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Nanoporous Carbon from Oil Palm Leaves via Hydrothermal Carbonization-Combined KOH Activation for Paraquat Removal
    (2022-08-01)
    Chanpee, Sirayu
    ;
    Kaewtrakulchai, Napat
    ;
    Khemasiri, Narathon
    ;
    Eiad-ua, Apiluck
    ;
    Assawasaengrat, Pornsawan
    In this study, nano-porous carbon was completely obtained from oil palm leaves (OPL) by hydrothermal pretreatment with chemical activation, using potassium hydroxide (KOH) as an activating agent. Potassium hydroxide was varied, with different ratios of 1:0.25, 1:1, and 1:4 (C: KOH; w/w) during activation. The physical morphology of nano-porous carbon has a spongy, sponge-like structure indicating an increase in specific surface area and porosity with the increasing amount of KOH activating agent. The highest specific surface area of OPL nano-porous carbon is approximately 1685 m<sup>2</sup>·g<sup>−1</sup>, with a total pore volume of 0.907 cm<sup>3</sup>·g<sup>−1</sup>. Moreover, the OPL nano-porous carbon significantly showed a mesoporous structure designed specifically to remove water pollutants. The adsorptive behavior of OPL nano-porous carbon was quantified by using paraquat as the target pollutant. The equilibrium analyzes were explained by the Langmuir model isotherm and pseudo-second-order kinetics. The maximum efficiency of paraquat removal in wastewater was 79%, at a paraquat concentration of 400 mg·L<sup>−1</sup>, for 10 min in the adsorption experiment. The results of this work demonstrated the practical application of nano-porous carbon derived from oil palm leaves as an alternative adsorbent for removing paraquat and other organic matter in wastewater.