Kiatkittipong, Kunlanan

Preferred name

Alternative Name

Kiatkittipong, K.

Main Affiliation

School of Engineering

kunlanan.kia@kmitl.ac.th

Now showing 1 - 9 of 9

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Catalytic Hydrotreating of Crude Pongamia pinnata Oil to Bio-Hydrogenated Diesel over Sulfided NiMo Catalyst
(2022-02-01)
Plaola, Yuwadee
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Leangsiri, Wanwipa
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Pongsiriyakul, Kanokthip
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Kiatkittipong, Worapon
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Srifa, Atthapon
This work studied the catalytic activity and stability of Ni-MoS2 supported on γ-Al2O3, SiO2, and TiO2 toward deoxygenation of different feedstocks, i.e., crude Pongamia pinnata oil (PPO) and refined palm olein (RPO). PPO was used as a renewable feedstock for bio-hydrogenated diesel production via catalytic hydrotreating under a temperature of 330 °C, H2 pressure of 50 bar, WHSV of 1.5 h−1, and H2/oil (v/v) of 1000 cm3/cm3 under continuous operation. The oil yield from a Soxhlet extraction of PPO was up to 26 wt.% on a dry basis, mainly consisting of C18 fatty acids. The catalytic activity in terms of conversion and diesel yield was in the same trend as increasing in the order of NiMo/γ-Al2O3 > NiMo/TiO2 > NiMo/SiO2. The hydrodeoxygenation (HDO) activity was more favorable over the sulfided NiMo supported on γ-Al2O3 and TiO2, while a high DCO was observed over the sulfided NiMo/SiO2 catalyst, which related to the properties of the support material and the intensity of metal–support interaction. The deactivation of NiMo/SiO2 and NiMo/TiO2 occurred in a short period, due to the phosphorus and alkali impurities in PPO which were not found in the case of RPO. NiMo/γ-Al2O3 exhibited the high resistance of impure feedstock with excellent stabil-ity. This indicates that the catalytic performance is influenced by the purity of the feedstock as well as the characteristics of the catalysts.
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Green pathway in utilizing CO2 via cycloaddition reaction with epoxide-A mini review
(2020-05-01)
Kiatkittipong, Kunlanan
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Shukri, Muhammad Amirul Amin Mohamad
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Kiatkittipong, Worapon
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Lim, Jun Wei
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Show, Pau Loke
Carbon dioxide (CO<inf>2</inf>) has been anticipated as an ideal carbon building block for organic synthesis due to the noble properties of CO<inf>2</inf>, which are abundant renewable carbon feedstock, non-toxic nature, and contributing to a more sustainable use of resources. Several green and proficient routes have been established for chemical CO<inf>2</inf> fixation. Among the prominent routes, this review epitomizes the reactions involving cycloaddition of epoxides with CO<inf>2</inf> in producing cyclic carbonate. Cyclic carbonate has been widely used as a polar aprotic solvent, as an electrolyte in Li-ion batteries, and as precursors for various forms of chemical synthesis such as polycarbonates and polyurethanes. This review provides an overview in terms of the reaction mechanistic pathway and recent advances in the development of several classes of catalysts, including homogeneous organocatalysts (e.g., organic salt, ionic liquid, deep eutectic solvents), organometallic (e.g., mono-, bi-, and tri-metal salen complexes and non-salen complexes) and heterogeneous supported catalysts, and metal organic framework (MOF). Selection of effective catalysts for various epoxide substrates is very important in determining the cycloaddition operating condition. Under their catalytic systems, all classes of these catalysts, with regard to recent developments, can exhibit CO<inf>2</inf> cycloaddition of terminal epoxide substrates at ambient temperatures and low CO<inf>2</inf> pressure. Although highly desired conversion can be achieved for internal epoxide substrates, higher temperature and pressure are normally required. This includes fatty acid-derived terminal epoxides for oleochemical carbonate production. The production of fully renewable resources by employment of bio-based epoxy with biorefinery concept and potential enhancement of cycloaddition reactions are pointed out as well.
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Mechanism of CaO catalyst deactivation with unconventional monitoring method for glycerol carbonate production via transesterification of glycerol with dimethyl carbonate
(2022-02-01)
Praikaew, Wanichaya
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Kiatkittipong, Worapon
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Aiouache, Farid
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Najdanovic-Visak, Vesna
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Termtanun, Mutsee
Glycerol carbonate (GC) was synthesized by transesterification of glycerol with dimethyl carbonate (DMC) using calcium oxide (CaO) derived from eggshell as a catalyst. The best results of 96% glycerol conversion and 94% GC yield were achieved under the following reaction conditions: 0.08 mole ratio of CaO to glycerol, 1:2.5 mole ratio of glycerol to DMC, 60°C reaction temperature, and 3 hours reaction time. As expected, CaO showed deteriorated catalytic performance when recycling as observed by a rapid decrease in GC yield. This research showed that the active CaO phase first was converted to calcium methoxide (Ca[OCH<inf>3</inf>]<inf>2</inf>) and calcium diglyceroxide (Ca[C<inf>3</inf>H<inf>7</inf>O<inf>3</inf>]<inf>2</inf>) and finally to carbonate phase (CaCO<inf>3</inf>) which can be confirmed by XRD patterns. According to the phase transformation, the basicity decreased from 0.482 mmol/g to 0.023 mmol/g, and basic strength altered from strong basic strength (15.0 < H_ < 18.4) to weak basic strength (7.2 < H_ < 9.8), resulting in the lower catalytic activity of the consecutive runs. Despite the fact that the GC selectivity was almost 100%, the reaction products (methanol and GC) were not obtained in their stoichiometric ratio and their extents corresponded with that of the catalyst phase transformation to CaCO<inf>3</inf>. The mechanism of CaO catalyzed transesterification based on the condensation reaction of glycerol and catalyst was proposed, and in situ formation of water-derivative species was hypothesized as a cause of CaO transformation. CaO could react with DMC and water, generating methanol and CaCO<inf>3</inf>. This enabled unconventional monitoring of catalyst deactivation by checking if the mole ratio of methanol to GC was higher than 2:1 of its reaction stoichiometric ratio. It was also demonstrated that calcination of post-run catalyst at 900°C to CaO exhibited almost constant catalytic activity, and the mole ratio of methanol to GC was constant at its reaction stoichiometry (2:1) for at least 4 times use.
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Effective Cu/Re promoted Ni-supported γ-Al2O3 catalyst for upgrading algae bio-crude oil produced by hydrothermal liquefaction
(2021-06-01)
Pongsiriyakul, Kanokthip
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Kiatkittipong, Worapon
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Adhikari, Sushil
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Lim, Jun Wei
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Lam, Su Shiung
Catalytic hydrotreating of algae bio-crude oil from hydrothermal liquefaction (HTL) of Nannochloropsis sp. was performed. Different Ni-based catalysts, including Ni/γ-Al<inf>2</inf>O<inf>3</inf>, Ni-Cu/γ-Al<inf>2</inf>O<inf>3,</inf> Ni-Re/γ-Al<inf>2</inf>O<inf>3,</inf> and Ni-Cu-Re/γ-Al<inf>2</inf>O<inf>3,</inf> (10%Ni, 5%Cu, 2.5%Re) were used in upgrading of the bio-crude oil. Most catalytic systems could effectively eliminate S and decrease the N and O contents, and enhance more than 20% improvement in the higher heating value (HHV) of the bio-oil (34 to 41–45 MJ/kg). Introducing only Cu could enhance the C[dbnd]O hydrogenation resulting in higher aromatic and alcohol compounds. While the addition of Re is effective for hydrodeoxygenation, it lowers denitrogenation due to amination reaction. Ni-Cu-Re/γ-Al<inf>2</inf>O<inf>3</inf> ternary alloy offered the best results on the overall performance, achieving the highest upgraded bio-oil yield of 58 wt% and the highest energy recovery in the upgrading process (ER<inf>upgrade</inf>) of 64.6%. As ER in HTL process (ER<inf>HTL</inf>) was ca. 71.8%, the overall ER (ER<inf>overall</inf>) from algae biomass to upgraded bio-oil of 46.4% can be achieved for Ni-Cu-Re/γ-Al<inf>2</inf>O<inf>3</inf> catalyst. Carbon efficiency approx. 47.7% can be attained as the carbon in the algae biomass feedstock was retained in the upgraded bio-oil. In addition, reaction pathways for the formation of different hydrotreated products catalyzed by mono-, bi-, and tri- metallic Ni-Cu-Re have been proposed.
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Process and energy intensification of glycerol carbonate production from glycerol and dimethyl carbonate in the presence of eggshell-derived cao heterogeneous catalyst
(2021-07-02)
Praikaew, Wanichaya
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Kiatkittipong, Worapon
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Aiouache, Farid
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Najdanovic-Visak, Vesna
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Ngaosuwan, Kanokwan
The process and energy intensifications for the synthesis of glycerol carbonate (GC) from glycerol and dimethyl carbonate (DMC) using an eggshell-derived CaO heterogeneous catalyst were investigated. The transesterification reaction between glycerol and DMC was typically limited by mass transfer because of the immiscible nature of the reactants. By varying the stirring speed, it was observed that the mass transfer limitation could be neglected at 800 rpm. The presence of the CaO solid catalyst made the mass transport-limited reaction process more prominent. Mass transfer intensification using a simple kitchen countertop blender as an alternative to overcome the external mass transfer limitation of a typical magnetic stirrer was demonstrated. A lower amount of the catalyst and a shorter reaction time were required to achieve 93% glycerol conversion or 91% GC yield, and the turnover frequency (TOF) increased almost 5 times from 1.5 to 7.2 min−1 when using a conventional magnetic stirrer and countertop blender, respectively. In addition, using a simple kitchen countertop blender with 7200 rpm, the reaction temperature of 60◦C could be reached within approximately 3 min without the need of a heating unit. This was the result of the self-frictional heat generated by the high-shear blender. This was considered to be heat transfer intensification, as heat was generated locally (in situ), offering a higher homogeneity distribution. Meanwhile, the trend toward energy intensification was promising as the yield efficiency increased from 0.064 to 2.391 g/kJ. A comparison among other process intensification techniques, e.g., microwave reactor, ultrasonic reactor, and reactive distillation was also rationalized.
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Biofuel upgrading via catalytic deoxygenation in trickle bed reactor: Crucial issue in selection of pressure regulator type
(2024-01-01)
Pongsiriyakul, Kanokthip
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Kiatkittipong, Worapon
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Lim, Jun Wei
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Najdanovic-Visak, Vesna
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Wongsakulphasatch, Suwimol
Trickle bed reactors (TBRs) are commonly used in various chemical and associated processes. The selection of a proper back pressure regulator (BPR) is crucial for maintaining the system's upstream pressure. In this study, we investigate the impact of BPR selection on deoxygenation reaction in a TBR with two typical types of BPR, including gas-phase type back pressure regulator (Gas-BPR) and multiphase type back pressure regulator (Multi-BPR). Notably, Gas-BPR introduces interruptions and pressure drops during the sampling step, impacting the hydrogen flow rate, while Multi-BPR ensures more consistent hydrogen flow. To examine the performance of BPR systems, hydrotreating experiments were conducted at 330 °C, 50 bar of hydrogen over Ni/γ-Al<inf>2</inf>O<inf>3</inf> catalyst using crude Pongamia pinnata oil as a feedstock and refined palm olein as a benchmark. Insignificant difference in the reaction performance between Multi-BPR and Gas-BPR systems was observed when using refined palm olein. Interestingly, there was a significant difference between the two systems when feeding with crude Pongamia pinnata oil. The multi-BPR system demonstrated superior performance, achieving 100% conversion of the feedstock over a prolonged period compared to the interrupted hydrogen flow in the Gas-BPR system. Further characterization of fresh and spent catalysts using N<inf>2</inf> sorption, XRD, SEM-EDS and TGA-DTG-DSC techniques revealed that a gum and coke formation was a reason for the rapid catalyst deactivation. Furthermore, the interrupted flow in the Gas-BPR system led to substantial gum production, ultimately causing a blockage in the reactor bed. Consequently, for feedstocks with high impurities, a robust continuous flow of hydrogen is essential. Thus, the study strongly recommends selecting Multi-BPR for continuous operation in TBRs to enhance efficiency and avoid catalyst deactivation.
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Simultaneous enhancement of photocatalytic bactericidal activity and strength properties of acrylonitrile-butadiene-styrene plastic via a facile preparation with silane/TiO2
(2020-04-01)
Kiatkittipong, Kunlanan
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Lim, Jun Wei
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Cheng, Chin Kui
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Kiatkittipong, Worapon
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Assabumrungrat, Suttichai
This work aims to enhance the photocatalytic antibacterial performance of plastics according to the JIS Z 2801:2010 standard, and to determine their mechanical properties by studying: (i) the influence of calcination on titanium dioxide (TiO<inf>2</inf>); (ii) modification with different TiO<inf>2</inf> concentrations, and; (iii) the effect of silane as a coupling agent. Acrylonitrile-butadiene-styrene plastics (ABS) and Escherichia coli (E. coli) were chosen as the model plastic and bacteria, respectively. The 500 °C calcined TiO<inf>2</inf> successfully provided the best photoantibacterial activity, with an approximately 62% decrease of E. coli colony counts following 30 min of exposure. Heat treatment improved the crystallinity of anatase TiO<inf>2</inf>, resulting in low electron-hole recombination, while effectively adsorbing reactants on the surface. ABS with 500 °C-calcined TiO<inf>2</inf> at the concentration of 1 wt % gave rise to the highest performance due to the improved distribution of TiO<inf>2</inf>. At this point, blending silane coupling agent could further improve the efficacy of photoantibacterial activity up to 75% due to greater interactions with the polymer matrix. Moreover, it could promote a 1.6-fold increase of yield strength via increased adherent bonding between TiO<inf>2</inf> and the ABS matrix. Excellent photocatalytic and material stability can be achieved, with constant photocatalytic efficiency remaining for up to five reuse cycles without loss in the yield strength.
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Comprehensive Review on Potential Contamination in Fuel Ethanol Production with Proposed Specific Guideline Criteria
(2022-05-01)
Wongsurakul, Peerawat
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Termtanun, Mutsee
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Kiatkittipong, Worapon
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Lim, Jun Wei
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Kiatkittipong, Kunlanan
Ethanol is a promising biofuel that can replace fossil fuel, mitigate greenhouse gas (GHG) emissions, and represent a renewable building block for biochemical production. Ethanol can be produced from various feedstocks. First-generation ethanol is mainly produced from sugar-and starch-containing feedstocks. For second-generation ethanol, lignocellulosic biomass is used as a feedstock. Typically, ethanol production contains four major steps, including the conversion of feedstock, fermentation, ethanol recovery, and ethanol storage. Each feedstock requires different procedures for its conversion to fermentable sugar. Lignocellulosic biomass requires extra pretreatment compared to sugar and starch feedstocks to disrupt the structure and improve enzymatic hydrolysis efficiency. Many pretreatment methods are available such as physical, chemical, physicochemical, and biological methods. However, the greatest concern regarding the pretreatment process is inhibitor formation, which might retard enzymatic hydrolysis and fermentation. The main inhibitors are furan derivatives, aromatic compounds, and organic acids. Actions to minimize the effects of inhibitors, detoxification, changing fermentation strategies, and metabolic engineering can subsequently be conducted. In addition to the inhibitors from pretreatment, chemicals used during the pretreatment and fermentation of byproducts may remain in the final product if they are not removed by ethanol distillation and dehydration. Maintaining the quality of ethanol during storage is another concerning issue. Initial impurities of ethanol being stored and its nature, including hygroscopic, high oxygen and carbon dioxide solubility, influence chemical reactions during the storage period and change ethanol’s characteristics (e.g., water content, ethanol content, acidity, pH, and electrical conductivity). During ethanol storage periods, nitrogen blanketing and corrosion inhibitors can be applied to reduce the quality degradation rate, the selection of which depends on several factors, such as cost and storage duration. This review article sheds light on the techniques of control used in ethanol fuel production, and also includes specific guidelines to control ethanol quality during production and the storage period in order to preserve ethanol production from first-generation to second-generation feedstock. Finally, the understanding of impurity/inhibitor formation and controlled strategies is crucial. These need to be considered when driving higher ethanol blending mandates in the short term, utilizing ethanol as a renewable building block for chemicals, or adopting ethanol as a hydrogen carrier for the long-term future, as has been recommended.
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Bioresources and biofuels—From classical to perspectives and trends
(2022-01-01)
Kiatkittipong, Worapon
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Pongsiriyakul, Kanokthip
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Lim, Jun Wei
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Kiatkittipong, Kunlanan
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Wongsurakul, Peerawat
This chapter provides perspective on “Bioresources and Biofuels” based on three platforms of bioresource feedstock, i.e., amorphous sugar, lipid, and lignocellulosics. A comprehensive scheme of various possibilities of biofuel production in the three platforms of feedstock that are already commercialized or under development is proposed. At present, only lipid platform dominates the production of “drop-in” biofuel in large volume. However, a coming electric vehicle revolution, disruptive technology, could be a threat to biofuel industries either electricity is produced from renewable energy or having carbon capture and sequestration (CCS) or not. Different alleviation approaches are discussed, for examples (1) shifting from ethanol to “Alcohol to jet, AtJ” or “Direct sugar to hydrocarbon, DSHC” in the amorphous sugar platform; (2) shifting from biodiesel or even bio-hydrotreated diesel (BHD) (also called Hydrogenated Esters and Fatty Acids, HEFA) to HEFA—Synthetic Paraffinic Kerosene (HEFA-SPK) in the lipid platform; and (3) shifting from Fischer-Tropsch (FT) to FT-Synthetic Paraffinic Kerosene (FT-SPK) and FT-SPK with Aromatics (FT-SPK/A) in the lignocellulosic biomass platform. Another interesting choice is on biofuel allocation to produce hydrogen and hydrogen carrier fuel for state-of-the-art fuel cell vehicle application. Last but not least, by using biorefinery concept, lipid/oleochemical biorefinery is specially emphasized and some current typical technologies such as fatty acid methyl ester biodiesel as well as coproduct glycerol should be shifted to more valuable oleochemicals are also mentioned in this chapter. Obviously, economic viability for biofuels and oleochemicals production is still a challenge today. Process intensification which aims to improve process performance substantially (with respect to equipment size, time, energy, etc.) is encouraged and illustrated as an example along the chapter.

Kiatkittipong, Kunlanan

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