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Exploration of characteristics and synthesis gas suitability for heat generation of coffee biomass pellets produced by single and co-pelletization
(2023-12-01)
Palamanit, Arkom
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Kongto, Pumin
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Chaiprapat, Sumate
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Dejchanchaiwong, Racha
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Chungcharoen, Thatchapol
Production of coffee beans generates various types of biomass that can be applied as bioenergy for drying and roasting the beans. Thus, the aims of this study were to explore the characteristics of coffee biomass pellets (CBPs) produced from coffee cherry pulp (CCP), coffee parchment (CPM), and expired green coffee beans (ECB) by single and co-pelletization. The CBPs were then used to produce the synthesis gas in a downdraft gasifier, and the syngas properties were investigated for further heat applications. The results showed that single and co-pelletization of CCP and CPM performed well. The CBPs had good physiochemical properties in shape, size, and atomic ratios. The higher heating value and energy density of CBPs were 19.25-24.29 MJ/kg and 12.09-14.87 GJ/m3. The ash from CBPs was rich in K2O, CaO and MgO oxides, and the CPM ash had the lowest initial deformation temperature at 1136 °C. The ash samples from CBPs also had different slagging and fouling indexes. The syngas from CBPs mainly contained H2 (6.85-9.30%), CO (12.15-18.85%), and CO2 (10.85-13.75%). The heating value and tar concentration of syngas from CBPs were 3.24-4.32 MJ/m3 and 21.75-30.92 g/m3. The main chemical compounds in tar were styrene, phenol, caffeine, and pyrrole according to GC-MS. These results indicate that CCP and CPM have potential for pelletization and gasification to generate heat needed for coffee bean processing.
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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.
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Impact of oil additive characteristics on biofuel engine wear using electron microscopy and confocal microscopy
(2019-01-01)
Rungsritanapaisan, Panyakorn
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Karin, Preechar
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Tanprayoon, Dhritti
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Tongsri, Ruangdaj
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Hanamura, Katsunori
Soot particles are produced during combustion process in the diesel engine. These particles will later exhaust into the thermosphere and part of them will contaminate the engine oil. When the lubricant is contaminated with soot, diesel engine abrasion or in a worst-case scenario lubricant starvation occurs. This situation will eventually lead into engine wear. High volume of soot also raises acid level of the area. If this state co-occurs with high temperature of the engine and volatile gases during operation, engine corrosion may also be produced. This research study the effect of additive volume on the dispersion of soot in engine oil and effect of additive on size and volume of soot which affect to mechanism of wear in metal by tribology four-ball tester, image analysis by scanning electron microscope and particle size analysis by laser diffraction technique.
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Effect of extra-framework cesium on the deoxygenation of methylester over CsNaX zeolites
(2011-12-15)
Danuthai, Tanate
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Sooknoi, Tawan
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Jongpatiwut, Siriporn
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Rirksomboon, Thirasak
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Osuwan, Somchai
The deoxygenation of methyl octanoate has been investigated over Cs-containing NaX zeolite catalysts at atmospheric pressure with He carrier gas and methanol as a co-feed. By varying the preparation procedures, different amounts of extra-framework Cs were left on the catalyst. The presence of extra-framework Cs affects the acid-basic characteristics of the catalysts and consequently their activity, stability, and particularly the product selectivity. That is, when the amount of extra-framework Cs increases, the corresponding increase in basicity enhances decarbonylation activity as well as catalyst stability. In this case, the deoxygenation of methyl octanoate on CsNaX catalysts was found to yield heptenes and hexenes as main products via surface decomposition of octanoate-like species. When the amount of extra-framework Cs was reduced, the hexene yield readily increased. The enhancement in hexene production can be ascribed to both, a decreased basicity that reduces decarbonylation and to a greater space available within the zeolite cavity for formation of a rather bulky cyclic-like intermediate that leads to hexene. In addition, weakly acidic sites, generated after the excess Cs was removed, resulted in relatively higher yield of inner-olefin product. When Cs was not present in the catalyst (i.e., NaX), other products such as aromatics and coupling compounds were observed. These compounds are less desirable for transportation fuel applications. © 2011 Elsevier B.V. All rights reserved.
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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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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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