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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
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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.
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Influence of hydrothermal-carbonization process on biochar properties from cattail weed waste
(2019-01-01)
Smuthkochorn, Araya
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Katunyoo, Nardnutda
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Kaewtrakulchai, Napat
;
Atong, Duangduen
;
Soongprasit, Kanit
Biochars have been successfully synthesized from Cattail leave (CL) via hydrothermal and carbonization process. The experimental work described has focused on physical properties of biochars produced from Cattail leaves at 160, 180 and 200°C for 8, 12 and 24 h for hydrothermal and substituted to carbonization at 700°C for 2 h. The influences of hydrothermal and carbonization on the pore structure, surface functional groups and the product yield was also investigated by characterization using Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy, respectively. Although the morphologies of cell structures were maintained in the hydrothermal and carbonization, it was found that the yield of produced biochar was decreased with increase of the hydrothermal temperature and time. The images from SEM showed that the pore structures are quite roughness on their external surface of biochar and the functional group of their surface area has most of pure carbon content (59-65 wt%).
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Influence of crystallization time for synthesis of zeolite a and zeolite x from natural kaolin
(2019-01-01)
Srilai, Suphada
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Tanwongwan, Worapak
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Onpecth, Kobchai
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Wongkitikun, Thanapat
;
Panomsuwan, Gasidit
Zeolite A and zeolite X were successfully synthesized from natural kaolin from Lampang province using calcination and a two-step hydrothermal method. First, metakaolin was obtained by calcining the kaolin at 700 °C for 2 h. Hydrothermal experiments can be separated into two types, being high temperature and short time or lower temperature long time. For high temperature hydrothermal treatment, metakaolin was mixed with NaOH to form hydrous sodium aluminosilicate. This was dissolved in dilute HCl. After filtration, the pH was adjusted with deionized water to pH = 7. This formed an amorphous aluminosilicate gel. For low temperature and longtime hydrothermal treatment aluminosilicate gel was mixed with NaOH to form zeolite A and zeolite X. The optimum condition for the first step in the synthesis of zeolite A is high temperature and short time of hydrothermal treatment with NaOH 8 M at 200 °C for 3 hours. This is followed by low temperature and longtime of hydrothermal treatment with NaOH 1 M carried out at 90 °C for 72 hours. The optimum conditions for the first step of synthesis of zeolite X is the high temperature, short time hydrothermal treatment with NaOH 8 M at 200 °C for 3 hours and low temperature, longtime hydrothermal treatment with NaOH 1 M at 90 °C for 120 hours. The characterizations of zeolite A and zeolite X were carried out by x-ray diffraction (XRD), scanning electron microscopy (SEM), and infrared spectroscopy (FT-IR).
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Zeolite P from kaolin via hydrothermal method
(2018-09-05)
Eiad-Ua, Apiluck
;
Amnaphiang, Phanwasa
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Asawaworarit, Panuruj
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Houngkamhang, Nongluck
;
Chollacoop, Nuwong
Zeolite P has been successfully synthesized from natural kaolin via two step hydrothermal process. The natural kaolin from Lampang, Thailand was studied for this research. In first hydrothermal, kaolin was mixed with sodium hydroxide solution at 200 <sup>o</sup>C for different reaction times from 3 - 5 hours, respectively.Sodium hydroxide and hydrochloric acid were added into the mixture to adjust their pH before they were formed into gel. Second hydrothermal process, the gel was kept of 90 <sup>o</sup>C for 3 days to obtain zeolite P. Synthesized zeolite P was characterized by X-ray diffraction (XRD) for identification the type and crystallization. Besides, the morphology was characterized by scanning electron microscopy)SEM.(The functional group was characterized by Fourier-transform infrared spectroscopy (FTIR). From this study, it was found that the increasing of reaction time in first hydrothermal activation and hydrochloric acid concentration lead to the high quality of zeolite P.
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Influence of hydrothermal and calcination process on metakaolin from natural clay
(2018-09-05)
Srilai, Suphada
;
Kaewtrakulchai, Napat
;
Panomsuwan, Gasidit
;
Fuji, Masayoshi
;
Eiad-Ua, Apiluck
In this study, metakaolin was synthesized from natural clay from Lampang province via hydrothermal and calcination process. The hydrothermal process was studied at different temperature from 160°C, 180°C and 200°C for 4, 8 and 12 hours. The calcination process was studied at different temperature from 500 to 900°C for 2 hours. Regarding the characterization, physical morphology of resulting products was observed by scanning electron microscope showing that the surface of resulting product was enhanced its surface area with more roughness when the temperature was increased. Moreover, FT-IR spectroscopy was applied for the chemical structure analysis indicating that Lampang clay can be transformed into metakaolin using hydrothermal at 200°C for 8 hours followed by the calcination at 800°C and 900°C as well as through the most condition for this studied. The improvement of the surface area of metakaolin leads to high metal dispersion for catalytic activity of the catalyst.

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