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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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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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Mechanistic investigation of Ni and NiCu for catalytic transfer hydrogenation of methyl levulinate to γ-valerolactone: A combined experimental and DFT study
(2023-06-25)
Chitpakdee, Chirawat
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Boonyoung, Pawan
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Pansakdanon, Chaianun
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Suttisintong, Khomson
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Faungnawakij, Kajornsak
Recently various supported bimetallic catalysts have been employed as effective catalysts for γ-valerolactone (GVL) production from levulinic acid or its esters. However, previous reports have shown synergetic roles of active metals and supports as important keys for superior catalytic performance. This work combines both experimental and simulation studies to focus solely on the role of bimetallic formation between nickel (Ni) and copper (Cu). The experimental results suggest that both Ni and nickel-copper alloy (NiCu) catalysts are good for hydrogenation of methyl levulinate (ML) to an intermediate species, 4-hydroxypentanoic acid (HPA). However, only NiCu has a better tendency to accelerate the conversion of HPA to GVL via cyclization process. Activation energy from experimental study of cyclization step over Ni is about two times larger than that of NiCu (E<inf>a</inf>K2 values are 121.7 and 56.0 kJ mol K−1 for Ni and NiCu, respectively) provided strong evidence of superior GVL production over NiCu catalyst. Density Functional Theory (DFT) simulation results reveal solid finding to support the high efficiency of NiCu over Ni catalyst for GVL production. The calculated energy barrier for HPA conversion to GVL over the NiCu is 1.0 eV which is lower than that of the Ni catalyst (1.54 eV). The Ni provided only one concerted pathway to transform from ML to GVL, while NiCu could provide either a concerted or nonconcerted pathway where the latter one requires lower activation energy for GVL production. The combination of these experimental and simulation results leads to a better understanding of bimetallic catalyst design for GVL production via catalytic transfer hydrogenation without any support materials.
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Surface Enhancement and Structure Formation of Metakaolin from Thailand Kaolin on the Various Calcination Temperature
(2020-01-01)
Tanwongwan, Worapak
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Wongkitikun, Thanapat
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Onpecht, Kobchai
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Srilai, Suphada
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Assabumrungrat, Suttichai
The metakaolin was chosen as a starting material for the synthesis of the zeolite because it is high crystallinity, reactivity and purity of raw material. Kaolin from Thailand which was selected from 3 different sources including Ratchaburi, Lampang, and Uttaradit were using as starting materials for synthesis of metakaolin by calcination temperature of this study were chosen in the range of 500 to 1000 °C for 2 h. Calcination temperature is significantly affect crystalline size, function group, and configuration of metakaolin by the results which obtained from X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy techniques were indicated that the best metakaolin was obtained from Uttaradit's kaolin which was calcined at 1000 oC for 2h by it shows the lowest impurities.
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Synthesis of zeolite x from bentonite via hydrothermal method
(2020-01-01)
Srilai, Suphada
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Tanwongwan, Worapak
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Onpecth, Kobchai
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Wongkitikun, Thanapat
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Panpiemrasda, Kollayut
Zeolite X were successfully synthesized from bentonite from Lopburi province, in Thailand using the two-step of hydrothermal method under optimum condition without calcination. The first step of hydrothermal were obtained at 200 ℃ for 3 h to remove unreacted impurity minerals such as quartz and muscovite. The secondary step of hydrothermal were obtained at 90 ℃ for 120 h for synthesis of zeolite X. The characterization of zeolite X were examined by x-ray diffraction (XRD), scanning electron microscopy (SEM), and infrared spectroscopy (FT-IR), respectively. The crystal structure of product was determined as zeolite X by XRD. The morphology of SEM images for zeolite X is octahedral shape. FTIR spectra are in accordance with the other characterization results.
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Simultaneous activation of copper mixed metal oxide catalysts in alcohols for gamma-valerolactone production from methyl levulinate
(2019-06-05)
Tanwongwan, Worapak
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Eiad-ua, Apiluck
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Kraithong, Wasawat
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Viriya-empikul, Nawin
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Suttisintong, Khomson
Catalytic transfer hydrogenation (CTH)of biomass-derivatives to value-added chemicals using metal-based catalysts is a promising process in biorefinery since it does not require high pressure of expensive and flammable hydrogen gas (H<inf>2</inf>). However, an activation of these catalysts using H<inf>2</inf> treatment prior to the CTH process limits this advantage. Here, copper mixed metal oxides are introduced as simultaneously activated catalysts (SACs)in the presence of alcohol for a production of gamma-valerolactone (GVL)from methyl levulinate (ML)without requirement of additional H<inf>2</inf> gas during both catalyst pretreatment and hydrogenation steps. Different alcohols were selected to function as hydrogen sources for both catalyst activation and ML hydrogenation. All copper mixed metal oxides, especially CuNiO showed significant potential as catalysts for ML conversion to GVL at 200 °C within 3 h. While 2-propanol and 2-butanol exhibited effective roles as hydrogen sources for simultaneous reductions of the catalysts to generate metal active sites and provided hydrogen species for hydrogenation of ML to GVL. Hydrogen temperature programmed reduction (H<inf>2</inf>-TPR), alcohol-assisted simultaneous reaction (ASR), in situ X-ray diffraction (in situ XRD)and X-ray photoelectron spectroscopy (XPS)revealed that the complementary cooperation between secondary alcohols and catalysts is the important key for the high GVL production in this work.
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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
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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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