Sooknoi, Tawan

Preferred name

Sooknoi, Tawan

Alternative Name

Sooknoi, T.

Main Affiliation

School of Science

tawan.so@kmitl.ac.th

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Reversible Hydrogenation-Dehydrogenation of Acetylpyridine-Pd-MIL-101(Cr) for Chemical Hydrogen Storage
(2020-10-07)
Makmeesub, Nuttapong
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Ritvirulh, Chonlada
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Choojun, Kittisak
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Chen, Teng Hao
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Poo-Arporn, Yingyot
3-Acetylpyridine (AcP), as an organic hydrogen carrier, and Pd nanoparticles, as a catalyst, were incorporated into MIL-101(Cr) for chemical hydrogen storage. AcP was first grafted into MIL-101(Cr), and then Pd (0.5-4.0 wt %) was encapsulated by a double-solvent adsorption process. Thermogravimetric analysis, inductively coupled plasma-optical emission spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, in situ X-ray adsorption near-edge structure analysis, 1H nuclear magnetic resonance (NMR), and elemental analysis suggested the existence of AcP and Pd nanoparticles (NPs) inside the MIL-101(Cr) cages. The chemical hydrogen storage of samples was evaluated by H2 temperature-programmed reaction. In situ Fourier transform infrared and 1H NMR techniques verified the hydrogenated and dehydrogenated forms of AcP upon hydrogen uptake. Reversible hydrogenation/dehydrogenation can be readily regulated by H2 partial pressure and temperature. The chemical hydrogen storage could be accomplished only when AcP and Pd NPs were adjacently present. The chemical hydrogen storage was enhanced with an increased Pd loading up to 0.33 mmol H2·g-1 per cycle. With the manipulation of hydrogenation and dehydrogenation temperatures at 150 °C, the chemical hydrogen storage can be maintained for up to 10 cycles. The material reported herein is one of the noncryogenic chemical hydrogen storages that can be operated at constant temperature and atmospheric pressure.
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Etherification of 2-methyl-pentanal on supported palladium
(2009-12-01)
Pham, Trung T.
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Crossley, Steven P.
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Sooknoi, Tawan
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Lobban, Lance L.
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Resasco, Daniel E.
Dialkyl ethers can be selectively produced from etherification of 2-methyl-pentanal and other oxygenates on supported Pd catalysts. Selectivities of 90% of ether were observed when feeding 2-methyl-pentanal and 2-methyl-pentanol at a molar ratio 1:1. Yields of up to 79 % have also been achieved. The reaction appears to be sensitive to metal particle features and molar feed ratios.
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Deoxygenation of model biofuel compounds over CsNaX zeolite catalyst
(2008-12-01)
Danuthai, Tanate
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Peralta, Maria A.
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Sooknoi, Tawan
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Osuwan, Somchai
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Lobban, Lance L.
The deoxygenation of methyl octanoate and benzaldehyde over CsNaX zeolite catalyst has been investigated as a model for reactions for production of hydrocarbon fuels from bio-oxygenates. The CsNaX zeolite used in the study was prepared by ion exchange of NaX with a CsNO<inf>3</inf>/CsOH solution to a 50% exchange level. The decarbonylation activity, selectivity, and stability of the CsNaX catalyst were enhanced when methanol was co-fed for the reaction of methyl octanoate. TPD studies suggest that methyl octanoate first decomposes to an octanoate-like species. The decomposition of such species leads to the formation of heptenes and hexenes as major products. Octenes and hydrogenated products are formed in lesser amounts via hydrogenation / hydrogenolysis using hydrogen produced on the surface from methanol decomposition, but not from gas phase H<inf>2</inf>.
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Condensation reactions of propanal over CexZr 1-xO2 mixed oxide catalysts
(2010-09-15)
Gangadharan, Anirudhan
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Shen, Min
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Sooknoi, Tawan
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Resasco, Daniel E.
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Mallinson, Richard G.
Vapor phase condensation reactions of propanal were investigated over Ce<inf>x</inf>Zr<inf>1-x</inf>O<inf>2</inf> mixed oxides as a model reaction to produce gasoline range molecules from short aldehydes found in bio-oil mixtures. Several operating parameters were investigated. These included the type of carrier gas used (H<inf>2</inf> or He) and the incorporation of acids and water in the feed. Propanal is converted to higher carbon chain oxygenates on Ce <inf>x</inf>Zr<inf>1-x</inf>O<inf>2</inf> by two pathways, aldol condensation and ketonization. The major products of these condensation reactions include 3-pentanone, 2-methyl-2-pentenal, 2-methylpentanal, 3-heptanone and 4-methyl-3-heptanone. It is proposed that the primary intermediate for the ketonization path is a surface carboxylate. The presence of acids in the feed inhibits the aldol condensation pathway by competitive adsorption that reduces the aldehyde conversion. Water also promotes ketonization and inhibits aldol condensation by increasing the concentration of surface hydroxyl groups that enhance the formation of surface carboxylates with the aldehyde. Hydrogen enhances cracking and production of light oxygenates and hydrocarbons. The light oxygenates may in turn be reincorporated into the reaction path, giving secondary products. However, the hydrocarbons do not react further. Analysis of the fresh and spent catalysts by XPS showed varying degrees of reduction of the oxide under different operating conditions that were consistent with the reaction results. Changing the proportion of the parent oxides showed that increased Zr favored formation of aldol products while increased Ce favored ketonization. This occurs by shifting the balance of the acid-base properties of the active sites. © 2010 Elsevier B.V.
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Conversion of 1- and 2-tetralone over HY zeolite
(2010-04-01)
Prasomsri, Teerawit
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Galiasso Tailleur, Roberto E.
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Alvarez, Walter E.
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Sooknoi, Tawan
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Resasco, Daniel E.
Conversion of 1- and 2-tetralone was investigated over acid HY zeolite under various reaction conditions in the vapor phase. Reactions were conducted in a fixed-bed reactor at 300, 400 and 500 °C in hydrogen atmospheric pressure. It was found that 1- and 2-tetralone are thermally unstable and thermal reaction has a contribution, particularly at high temperatures. The reactivity of 2-tetralone was significantly higher than that of 1-tetralone. This behavior is more pronounced in the presence of acid HY zeolite. For both isomers, the main products were naphthol, coupling compounds (4-ring), naphthalene and tetralin. Trace amounts of dihydronaphthalene, ring-contraction and ring-opening product were also observed. At high temperatures, isomerization and dehydration of naphthol were observed over the HY zeolite. It seems that on the acidic zeolite, hydrogen transfer plays a significant role in determining the reaction path. © 2010 Springer Science+Business Media, LLC.
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Oligomerization of propionaldehyde on novel basic catalysts
(2008-12-01)
Amen, Q. V.
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Sooknoi, T.
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Lobban, L. L.
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Mallinson, R. G.
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Resasco, Daniel E.
Vapor-phase oligomerization of propanal to 2-methyl-2-pentenal and 2-ethyl-3,5-dimethylcyclo-2-pentenone over basic zeolite catalysts (NaX, KNaX, KX, and CsNaX), as well as more traditional solid basic catalysts (MgO and MgO-Al2O3 hydrotalcites), was studied in an integral flow reactor at atmospheric pressure. Conversion and carbon yield based on catalyst properties (basicity, acidity) are reported. The highest stable activity was over KX, with the highest selectivity to the primary product, 2-methyl-2-pentenal (dehydrated aldol dimer of propanal) and the second highest selectivity to the secondary product, 2-ethyl-3,5-dimethylcyclo-2-pentenone (a non-aromatic cyclic trimer), with essentially no other products. Promotion of Zeolite X with various alkali metals also affected the acid and base site strengths, which had an effect on the conversion and selectivity.
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A comparison of the reactivities of propanal and propylene on HZSM-5
(2010-05-04)
Hoang, Trung Q.
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Zhu, Xinli
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Sooknoi, Tawan
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Resasco, Daniel E.
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Mallinson, Richard G.
The reactivities of propanal and propylene have been compared over HSZM-5 zeolites (Si/Al = 45 and 25). Propanal is found to be much more reactive than propylene and to form mostly 2-methyl-2-pentenal and C<inf>9</inf> aromatics as early products in the reaction network. Propylene, in contrast, requires more severe conditions to form C<inf>6</inf> and C<inf>7</inf> aromatics. It is proposed that propanal undergoes acid-catalyzed aldol condensation to form 2-methyl-2-pentenal. This dimer undergoes further condensation to form the aldol trimer, which subsequently dehydrates and cyclizes into C<inf>9</inf> aromatics. In contrast, it is well known that propylene, like other olefins, undergoes aromatization via oligomerization and formation of a hydrocarbon pool. While in the conversion of propanal, propylene is also produced, it appears that it does not play a major role in the formation of aromatics under conditions of shorter space times and lower temperatures, at which propanal produces aromatics in significant amounts. © 2010 Elsevier Inc. All rights reserved.
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Highly stable Pd2+ species anchoring on ethylenediamine-grafted-MIL-101(Cr) as a robust oxidation catalyst†
(2022-02-01)
Makmeesub, Nuttapong
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Ritvirulh, Chonlada
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Choojun, Kittisak
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Sattayaporn, Suchinda
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Resasco, Daniel E.
Highly stable Pd2+ species were anchored on ethylenediamine-grafted MIL-101(Cr). Ethylenediamine (0.3-1.2 mmol g−1) was first grafted onto MIL-101(Cr), then Pd2+ (0.03-0.2 mmol Pd per g) was incorporated by double-solvent adsorption. Fourier transform infrared, inductively coupled plasma-optical emission spectroscopy, transmission electron microscopy and CHN analysis confirmed the incorporation of ethylenediamine and Pd2+ in MIL-101(Cr). X-ray photoelectron and Raman spectroscopy suggested that one amino moiety of ethylenediamine coordinated with the Cr3+ nodes of MIL-101(Cr). The other served as an anchoring site for the incorporated Pd2+ species. In situ X-ray absorption near-edge structure analysis showed that the strong interaction between Pd2+ and ethylenediamine, within the confinement of the MIL-101(Cr) structure, effectively prevented reduction to Pd0, even in the presence of H<inf>2</inf> at 150 °C. At relatively low temperatures, the catalysts with ethylenediamine : Pd2+ molar ratios of 10 provided a higher activity for styrene oxidation (TOF ∼30 h−1), as compared to previous reports. The presence of ethylenediamine as an anchoring ligand also inhibited the reduction of Pd2+ by the feed (styrene) and minimized leaching of the active Pd2+ species under oxidizing and acidic conditions. The Pd2+ species anchoring on ethylenediamine-grafted-MIL-101(Cr) exhibited an improved catalytic activity and stability, as compared to typical liquid-phase oxidation catalysts.
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Conversion of propylene and propanal on HZSM-5
(2009-12-01)
Hoang, Trung Q.
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Zhu, Xinli
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Sooknoi, Tawan
;
Resasco, Daniel E.
;
Lobban, Lance L.
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Conversion of 1-tetralone over HY zeolite: An indicator of the extent of hydrogen transfer
(2010-12-01)
Prasomsri, Teerawit
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Galiasso Tailleur, Roberto E.
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Alvarez, Walter E.
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Sooknoi, Tawan
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Resasco, Daniel E.
The conversion of pure 1-tetralone and its mixtures with n-decane, decalin, tetralin, or 1,5-dimethyl tetralin (DMT) has been investigated over HY zeolite. The dominant reactions undergone by 1-tetralone are the dehydrogenation to 1-naphthol and the subsequent isomerization to 2-naphthol. In the presence of hydrocarbons, the hydrogen transfer/dehydration of naphthols is accelerated, and naphthalene is formed in different amounts, depending on the nature of the co-fed hydrocarbon. In this contribution, it is demonstrated how the product distribution from the tetralone conversion can be used as an indicator of the hydrogen transfer ability of a particular hydrocarbon, or mixture of hydrocarbons. The relative order of hydrogen transfer ability of the various hydrogen donating compounds, as inferred from the naphthalene-to-naphthol product ratio, is DMT > tetralin ≈ decalin > n-decane. This trend agrees well with the hydride dissociation energy of individual donors calculated by DFT. © 2010 Elsevier B.V. All rights reserved.

Sooknoi, Tawan

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