Na Ranong, Duangkamol

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Na-Ranong, Duangkamol

Na-Ranong, D.

duangkamol.na@kmitl.ac.th

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Recovery of useful chemicals from oil palm shell-derived oil using zirconia supporting iron oxide catalysts
(2008-05-01)
Na-Ranong, Duangkamol
;
Yuangsawad, Ratanaporn
;
Tago, Teruoki
;
Masuda, Takao
The possibility for recovering methanol, acetic acid and phenol from oil palm shell-derived oil was investigated. Thermal cracking mainly produced a solid residue and was not a suitable method for recovering these three target chemicals. When zirconia supporting iron based catalyst (Zr/FeOx, Zr-FeOx or Zr-Al-FeOx) was applied, the "others"-unidentified hydrocarbons-were satisfactorily removed without formation of a solid residue while these target compounds were considerably stable over these catalysts. Zr-Al-FeOx showed the highest activity for oxidation of the oil to CO<inf>2</inf>. Effect of operating parameters (steam to oil ratio, temperature and time factor) on its performance was further investigated. In order to gain insight into the reaction path, the reaction using model compounds (methanol, acetic acid, acetone, ethyl acetate and phenol) was performed. © 2008 Springer.
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Kinetics, isotherm, and thermodynamics of adsorption of sterol on strong acid ion exchange resin
(2018-01-01)
Ladadok, Chinakrit
;
Yamaki, Takehiro
;
Matsuda, Keigo
;
Matsumoto, Hideyuki
;
Na-Ranong, Duangkamol
Kinetics, isotherm and thermodynamics of sterol adsorption on styrene-divinylbenzene based ion-exchange resin with strong acid was investigated at temperature in the range of 298 to 313 K using a model solution of stigmasterol in n-heptane with initial concentration in the range of 0.3×10-3 to 1.8×10-3 kg/kg-solution. Adsorbent (5 wt%) was added to the model solution and isothermal adsorption was performed at 3.33 rps for 7.2×103 s. Kinetics of sterol adsorption was analysed based on pseudo-first-order and pseudo-second-order models. The results revealed that pseudo-second-order model agreed with the experimental data, much better than pseudofirst- order model. At the equilibrium of adsorption, adsorption capacity (qe) decreased when the temperature was increased. This result indicated that sterol adsorption was exothermic. Analysis of adsorption isotherm data based on Langmuir, Freundlich and linear models showed that Freundlich was the best model that could predict the adsorption isotherm data. Adsorption equilibrium constants calculated based on Freundlich model at various temperatures were used to calculate Gibb's free energy change (ΔG), enthalpy change (ΔH), and entropy change (ΔS). The increase of ΔG with respect to temperature indicated that the adsorption was more favourable at lower temperatures. The negative value of ΔH indicated that the adsorption was exothermic and agreed well with the effect of temperature on adsorption capacity. The negative value of ΔS indicated associative adsorption and decrease of the randomness between the solid/liquid interfaces due to the adsorption.
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Effect of quenching medium on photocatalytic activity of nano-TiO2 prepared by solvothermal method
(2008-05-01)
Supphasrirongjaroen, Piyawat
;
Praserthdam, Piyasan
;
Panpranot, Joongjai
;
Na-Ranong, Duangkamol
;
Mekasuwandumrong, Okorn
Pure anatase nano-TiO<inf>2</inf> powders were synthesized by solvothermal method using titanium butoxide as the precursor and were subjected to a rapid quenching in various media such as H<inf>2</inf>O, H<inf>2</inf>O<inf>2</inf>, air, and liquid N<inf>2</inf> as a post-synthesis treatment. By creating a thermal shock effect, quenching process has shown to be an easy novel route for modifying surface defects of the nano-TiO<inf>2</inf> and its photocatalytic activity. In this study, the TiO<inf>2</inf> sample quenched in air at 77 K contained the highest amount of Ti3+ surface defect with the highest Ti3+/OH and was found to exhibit the highest photocatalytic activity for ethylene decomposition. © 2007 Elsevier B.V. All rights reserved.
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Oxidative cracking of aromatic compounds related to lignin constituents with steam using ZrO2-Al2O3-FeOx catalyst
(2010-10-22)
Yoshikawa, Takuya
;
Na-Ranong, Duangkamol
;
Tago, Teruoki
;
Masuda, Takao
The catalytic activity of iron oxide composite catalyst (ZrO <inf>2</inf>-Al<inf>2</inf>O<inf>3</inf>-FeO<inf>x</inf>) was investigated for converting aromatic compounds derived from plant biomass into useful aromatics. Catalytic cracking of lignin constituent-related di-aroatics such as diphenyl ether, diphenyl methane, and 2-benzyloxyphenol, and mono-aromatics such as guaiacol, acetophenone, and 1-phenyl-1-propanol was carried out over ZrO <inf>2</inf>-Al<inf>2</inf>O<inf>3</inf>-FeO<inf>x</inf>. The catalytic reactions were conducted in a fixed-bed reactor at 773 K under atmospheric pressure. Diphenyl ether and diphenyl methane were stable, whereas 2-benzyloxyphenol was thermally decomposed, followed by the production of toluene and phenol over ZrO<inf>2</inf>-Al<inf>2</inf>O<inf>3</inf>-FeO <inf>x</inf>. Guaiacol and acetophenone were selectively converted into 54 C-mol% of phenol and 29 C-mol% of benzene, respectively. The methoxy and carbonyl groups were decomposed into gaseous products mainly consisting of CO<inf>2</inf>, whereas dehydration of the aliphatic hydroxyl group in 1-phenyl-1-propanol mainly occurred to produce 1-phenyl-1-propene. ZrO <inf>2</inf>-Al<inf>2</inf>O<inf>3</inf>-FeO<inf>x</inf> catalyst is effective for degrading alkyl ether bonds between aromatic rings, and the ring substituent methoxy and carbonyl groups.
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Application of periodic operation to kinetic study of NO-CO reaction over Rh/Al2O3
(2009-02-01)
Na-Ranong, Duangkamol
;
Yuangsawad, Ratanaporn
;
Kitchaiya, Prakob
;
Aida, Takashi
A concentration forcing periodic operation has been applied incorporating with a conventional steady-state rate measurement in order to study the kinetics of NO-CO reaction over Rh/Al<inf>2</inf>O<inf>3</inf> at 423 K. The steady-state rate data obtained using a differential fixed-bed reactor showed that the order of the reaction was 0 with respect to CO concentration (C<inf>CO</inf>) and 0.4 with respect to NO concentration (C<inf>NO</inf>). Under the periodic condition, where a square wave was applied for NO and CO feeding, a deformation of the C<inf>NO</inf> wave was observed at the outlet of an integral fixed-bed reactor. Shape of the deformed C<inf>NO</inf> wave indicates that both reactants were strongly adsorbed on catalytic active sites. Three plausible mechanisms that could explain the strong adsorption of these two reactants together with insignificant self-inhibition effect of the strong adsorption on the rate were considered: (I) Langmuir-Hinshelwood (L-H), (II) Eley-Redial-like (E-R-like) and (III) combined L-H and E-R-like mechanisms. A one-dimensional pseudohomogeneous reactor model coupled with the reaction mechanisms was employed to simulate the characteristics of the rate data and the shape of the deformed C<inf>NO</inf> wave. Only the E-R-like mechanism could predict these characteristics of steady and periodic operations by employing one set of kinetic parameters while the other mechanisms needed different sets of the parameters to predict the characteristics. Sensitivity of each parameter to the shape of the C<inf>NO</inf> wave was analyzed and value of each parameter was determined for the E-R-like mechanism. The reliabilities of the proposed mechanism and its parameters were evaluated. © 2008 Elsevier B.V. All rights reserved.
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Synthesis of moleculary imprinted polymer originated from TFMAA and TRIM for sterol separation
(2018-01-01)
Ladadok, Chinakrit
;
Sinpichai, Sarawut
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Nonthanasin, Nattawat
;
Binabdullah, Krittin
;
Na-Ranong, Duangkamol
Molecular imprinted polymer (MIP) was synthesized bulk polymerization using 2-(trifluoromethyl)acrylic acid (TFMAA) as a functional monomer, trimethylolpropane trimethacrylate (TRIM) as a cross-linker, benzoyl peroxide as an initiator, acetone as porogen solvent, and stigmasterol as template molecule to obtain adsorbent having high affinity and selectivity to stigmasterol for separation of stigmasterol or other sterols in liquid phase. Functional groups and the morphology of the obtained MIP were investigated by Fourier transform infrared (FTIR) and scanning electron microscope (SEM), respectively. The performance in sterol adsorption of MIPs synthesized under various conditions was investigated using a model solution of sterol mixture in n-heptane with initial concentration of 1.40×10-4 kg/kg-solution comparing with non-imprinted polymer (NIP). Adsorbent (1 wt%) was added to model solution and shaken in an orbital shaker at 3.67 rps, 303 K for 2.16×104 s. The analysis of variance (ANOVA) suggested that the cross-linker was more influential factor on the adsorption performance of MIP as compared to the template molecule and solvent. The optimization showed that MIP synthesized at 0.5×10-3 mol of cross-linker, 1.0×10-4 mol of template molecule, and 1.0×10-5 m3 of solvent had highest percentage adsorption of 57.73 % which was 1.37 times of NIP.
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Amplification of periodic temperature disturbances in a packed-bed reactor: CO oxidation over a CuO/Al2O3 catalyst
(2003-01-01)
Na-Ranong, Duangkamol
;
Jaree, Attasak
;
Hudgins, Robert R.
;
Budman, Hector M.
;
Silveston, Peter L.
Amplification of periodic variations of input temperature in a product-inhibited reaction - CO oxidation over CuO-γ-Al<inf>2</inf>O <inf>3</inf> - was investigated experimentally in an insulated packed-bed reactor. At steady state the temperature profile was elongated compared with that of a reactant-inhibited CO oxidation over Pt/Al<inf>2</inf>O<inf>3</inf>, studied elsewhere. Under periodic operation, amplitudes of the resulting travelling temperature waves, monitored downstream from the reaction front, were amplified to a greater extent than those in the reactant-inhibited CO oxidation over Pt/Al<inf>2</inf>O<inf>3</inf>. The magnitude of the amplification depended on the perturbation frequency and showed resonance behaviour. The magnitude decreased monotonically with increasing perturbation amplitude.
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Precipitation above cloud point in palm oil based biodiesel during production and storage
(2014-04-15)
Na-Ranong, Duangkamol
;
Kitchaiya, Prakob
Precipitation of a white solid in palm oil based biodiesel (PO-B100) can be found even in PO-B100 that contains minor contaminants (i.e. mono-, di- and triglycerides) within the limitation according to EN-14214 and Thailand's regulation. To identify compounds causing this precipitation, the precipitates collected at the temperature near cloud point and at room temperature were characterized using a gas chromatograph-flame ionization detector, gas chromatograph-mass spectrometry and fourier transform-infrared. The result indicated that the compounds causing the precipitation were steryl glucosides, not glycerides, regardless of temperature. Therefore, effect of steryl glucosides on precipitation time was further investigated using PO-B100s with different amounts of steryl glucosides, mono-, di- and triglycerides. The result revealed that precipitation time of the PO-B100 with high concentration of steryl glucosides was much less than the one without steryl glucosides and decreasing steryl glucosides concentration to 20 ppm significantly improved storage stability of PO-B100. In addition, the precipitation time was not influenced by concentration of mono-, di- and triglycerides. © 2014 Elsevier Ltd. All rights reserved.
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Biodiesel produced from transesterification of palm oil using NaOH-treated activated carbon and pyrolytic char of used tires as catalysts
(2025-03-01)
Chana, Khulanuttha
;
Chen, Bing Hung
;
Na-Ranong, Duangkamol
Biodiesel produced from catalyzed transesterification of palm oil with methanol using NaOH-treated carbonaceous catalysts was studied and reported. Particularly, effect of the carbonaceous support, i.e. activated carbon (AC) and pyrolytic char of end-of-life used tire (TPC), on the yield of biodiesel was investigated. The resultant yield of biodiesel near 98.5 % could be attained from transesterification reactions conducted with a catalyst loading at 5 wt% of palm oil initially used, under a molar ratio of methanol/oil at 21/1, at 65°C and 180 min for reaction temperature and time. The kinetics of the transesterification reaction could be fitted satisfactorily with the pseudo first-order model. The Arrhenius behavior was observed from the temperature-dependent rate constants, leading to an activation energy at 111.2 kJ/mol if AC-supporting catalyst was used. Both AC and TPC-supporting catalysts could produce biodiesel with a yield greater than 90 % even after the fourth cycles of catalyzed transesterification reactions. Notably, the feasibility in the upcycling of TPC as catalyst support was demonstrated in this work.
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Kinetics, isotherm and thermodynamics of sterol adsorption on styrene-divinylbenzene anion-exchange resins
(2018-10-01)
Ladadok, Chinakrit
;
Yamaki, Takehiro
;
Matsuda, Keigo
;
Matsumoto, Hideyuki
;
Na-Ranong, Duangkamol
Phytosterols can be recovered from natural resources using molecular distillation, cold crystallization, which require large energy consumption. Adsorption was considered as a feasible alternative method. In this study, kinetics, isotherm and thermodynamics of stigmasterol adsorption on styrene-divinylbenzene with two different functional groups, strong base (SB-R) and weak base (WB-R), were investigated using a model solution of stigmasterol in n-heptane. Isothermal adsorption experiments were performed in temperature range of 298-313 K and concentration range of 0.3-6.0 mg/g<inf>sol</inf>. For both SB-R and WB-R cases, kinetics of adsorption was analysed based on pseudofirst- order and pseudo-second-order models and the results revealed that pseudo-second-order model agreed with the experimental data much better than pseudo-first-order model. Analysis of isotherm data based on Langmuir, Freundlich and linear models showed that Freundlich was the best model that could predict behaviour of sterol adsorption for both SB-R and WB-R cases. In addition, thermodynamics parameters (δG, δH andδS) indicated that the sterol adsorptions on these adsorbents were spontaneous, exothermic and favourable at low temperature.

Na Ranong, Duangkamol

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