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1. Continuous Catalyst-Free Production of Biodiesel through Transesterification of Soybean Fried Oil in Supercritical Methanol and Ethanol

Author:
Gonzalez, Samantha L.; Sychoski, Melania M.; Navarro-Díaz, Helmut J.; Callejas, Nicolás; Saibene, Marcela; Vieitez, Ignacio; Jachmanián, Iván; da Silva, Camila; Hense, Haiko; Oliveira, J. Vladimir
Source:
Energy & Fuels 2013 v.27 no.9 pp. 5253-5259
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; biodiesel; ethanol; fatty acid methyl esters; fatty acids; methanol; oils; soybeans; temperature; transesterification; wastes;     Show all 11 Subjects
Abstract:
... This work reports the production of fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs) by means of waste fried oil (WFO) transesterification using methanol and ethanol at supercritical conditions, in a continuous catalyst-free process. Transesterification experiments were performed from 573 to 623 K, at 10, 15, and 20 MPa, with oil/alcohol molar ratios of 1:20, 1:30, and 1:40 and ...
DOI:
10.1021/ef400869y

2. Influence of Carbonate Ester Molecular Structure on Compression Ignition Combustion and Emissions

Author:
Hellier, Paul; Ladommatos, Nicos; Allan, Robert; Rogerson, John
Source:
Energy & Fuels 2013 v.27 no.9 pp. 5222-5245
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; alcohols; carbon dioxide; chemical structure; combustion; emissions; esters; fuels; nitrates; oxygen; particulates; temperature;     Show all 12 Subjects
Abstract:
... A primary motivation for the development of future fuels is to halt the increasing concentration of atmospheric carbon dioxide. As such, a fuel that can potentially be produced from a feedstock of alcohols and atmospheric carbon dioxide is an attractive proposition. Symmetrical carbonate esters may thus offer a sustainable means of converting alcohols to larger molecules that are potentially bette ...
DOI:
10.1021/ef401415j

3. Biomass Hydropyrolysis in a Pressurized Fluidized Bed Reactor

Author:
Dayton, David C.; Carpenter, John; Farmer, Justin; Turk, Brian; Gupta, Raghubir
Source:
Energy & Fuels 2013 v.27 no.7 pp. 3778-3785
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; biomass; catalysts; energy; fluidized beds; heat transfer; hydrogen; oxygen; pyrolysis; streams; temperature;     Show all 11 Subjects
Abstract:
... Biomass pyrolysis and hydropyrolysis have been studied in a high-temperature, high-pressure fluidized bed reactor system. The reactor system can be operated at reaction temperatures up to 982 °C (1800 °F) and pressures up to 4 MPa (600 psi). Baseline biomass pyrolysis experiments with an inert heat transfer material were conducted at various pressures and hydrogen partial pressures to determine th ...
DOI:
10.1021/ef400355t

4. Hydrocracking of Maya Vacuum Residue with NiMo Catalysts Supported on Mesoporous Alumina and Silica–Alumina

Author:
Purón, Holda; Pinilla, José Luis; Berrueco, César; Montoya de la Fuente, J. A.; Millán, Marcos
Source:
Energy & Fuels 2013 v.27 no.7 pp. 3952-3960
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; aluminum oxide; catalysts; cracking; hydrocarbons; oils; petroleum; porosity; porous media; temperature;     Show all 10 Subjects
Abstract:
... Hydrocracking of heavy oils poses greater challenges than that of lighter feeds in terms of catalyst properties and resistance to deactivation. The development of larger pore size catalysts may be beneficial to improve their effectiveness toward cracking the larger molecules present in these feedstocks. Mesoporous alumina and mesoporous silica–alumina (MSA) with different textural properties were ...
DOI:
10.1021/ef400623f

5. Detailed Analysis of Residual Volatiles in Chars from the Pyrolysis of Biomass and Lignite

Author:
Yang, Hua; Kudo, Shinji; Hazeyama, Seira; Norinaga, Koyo; Mašek, Ondřej; Hayashi, Jun-ichiro
Source:
Energy & Fuels 2013 v.27 no.6 pp. 3209-3223
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; benzene; biomass; gas chromatography-mass spectrometry; gasification; lignite; pyrolysis; soot; temperature;     Show all 9 Subjects
Abstract:
... Pyrolysis of biomass or coal, if operated at temperature high enough to complete tar evolution, is expected to give resulting char a tar-free nature. Use of such tar-free char instead of the original fuel in gasification would reduce or even completely eliminate the need for use of complex devices/mechanisms for tar/soot removal. Increasing pyrolysis temperature may not only decrease the content o ...
DOI:
10.1021/ef4001192

6. Effect of Torrefaction on Bio-oil Upgrading over HZSM-5. Part 1: Product Yield, Product Quality, and Catalyst Effectiveness for Benzene, Toluene, Ethylbenzene, and Xylene Production

Author:
Hilten, Roger N.; Speir, Richard A.; Kastner, James R.; Mani, Sudhagar; Das, K. C.
Source:
Energy & Fuels 2013 v.27 no.2 pp. 830-843
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; BTEX (benzene, toluene, ethylbenzene, xylene); biofuels; biomass; catalysts; catalytic cracking; product quality; pyrolysis; temperature; torrefaction;     Show all 10 Subjects
Abstract:
... A three-step bio-oil production process involving torrefaction pretreatment (at 225, 250, or 275 °C with a 20 min hold time), pyrolysis (at 500 °C with two heating rates), and secondary catalytic processing over HZSM-5 (at 400, 450, or 500 °C) was studied to determine process effects, particularly of torrefaction, on the yield of liquid and aromatic hydrocarbons and the quality of upgraded bio-oil ...
DOI:
10.1021/ef301694x

7. Kinetic Behavior of Torrefied Biomass in an Oxidative Environment

Author:
Tapasvi, Dhruv; Khalil, Roger; Várhegyi, Gábor; Skreiberg, Øyvind; Tran, Khanh-Quang; Grønli, Morten
Source:
Energy & Fuels 2013 v.27 no.2 pp. 1050-1060
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Betula; Picea; biomass; cellulose; combustion; heat; kinetics; models; oxygen; superoxide anion; temperature; thermogravimetry; wood;     Show all 14 Subjects
Abstract:
... The combustion of four torrefied wood samples and their feedstocks (birch and spruce) was studied at slow heating programs, under well-defined conditions by thermogravimetry (TGA). Particularly low sample masses were employed to avoid the self-heating of the samples because of the huge reaction heat of the combustion. Linear, modulated, and constant reaction rate (CRR) temperature programs were em ...
DOI:
10.1021/ef3019222

8. The Effect of Additional Zeolites in Amorphous Silica–Alumina Supports on Hydrocracking of Semirefined Paraffinic Wax

Author:
Jiang, Jian; Dong, Zhaohui; Chen, Haoyi; Sun, Jibing; Yang, Chao; Cao, Fahai
Source:
Energy & Fuels 2013 v.27 no.2 pp. 1035-1039
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; catalysts; combustion; distillates; models; silica; sol-gel processing; temperature; transmission electron microscopy; zeolites;     Show all 10 Subjects
Abstract:
... The amorphous SiO₂–Al₂O₃ supports (SA-x) with different SiO₂ weight ratios (x) were prepared by a sol–gel method. The NiW active components were loaded over the supports using an organic matrix combustion method. Semirefined 56# wax was used as the model feedstock of F-T synthetic wax for hydrocracking in a single fixed-bed reactor. The started reaction was conducted at the temperature of 380 °C, ...
DOI:
10.1021/ef3013807

9. Comparative Assessment of Wet Torrefaction

Author:
Bach, Quang-Vu; Tran, Khanh-Quang; Khalil, Roger Antoine; Skreiberg, Øyvind; Seisenbaeva, Gulaim
Source:
Energy & Fuels 2013 v.27 no.11 pp. 6743-6753
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Betula; Picea abies; ash content; autoclaves; biofuels; biomass; hardwood; particle size; prediction; regression analysis; softwood; temperature; torrefaction; vapor pressure;     Show all 15 Subjects
Abstract:
... Wet torrefaction of typical Norwegian biomass fuels was studied within the temperature window of 175–225 °C, using a benchtop autoclave reactor of 250 mL in volume from Parr Instrument. Two types of local biomass fuels were employed as feedstock, Norway spruce (softwood) and birch (hardwood). Effects of process parameters including pressure, reaction temperature, holding time, and feedstock partic ...
DOI:
10.1021/ef401295w

10. Influence of Feedstock on the Release of Potassium, Sodium, Chlorine, Sulfur, and Phosphorus Species during Gasification of Wood and Biomass Shells

Author:
Bläsing, Marc; Zini, Mostafa; Müller, Michael
Source:
Energy & Fuels 2013 v.27 no.3 pp. 1439-1445
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; biomass; chlorine; data collection; elemental composition; furnaces; gases; phosphorus; potassium; sodium; spectrometers; sulfur; temperature; trace elements; wood;     Show all 15 Subjects
Abstract:
... The objective of this work was to investigate the influence of feedstock on the release of trace elements during gasification. Therefore, different types of woody biomass and biomass residues (shells) were thermochemically converted in an atmospheric flow channel reactor furnace at different temperatures (900, 1200, and 1400 °C) under gasification-like conditions. For the determination of the comp ...
DOI:
10.1021/ef302093r

11. Effect of Torrefaction on Bio-oil Upgrading over HZSM-5. Part 2: Byproduct Formation and Catalyst Properties and Function

Author:
Hilten, Roger N.; Speir, Richard A.; Kastner, James R.; Mani, Sudhagar; Das, K. C.
Source:
Energy & Fuels 2013 v.27 no.2 pp. 844-856
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; acetic acid; biofuels; biomass; byproducts; catalysts; formic acid; furfural; hydrogen; hydroxymethylfurfural; porosity; pyrolysis; surface area; temperature; torrefaction;     Show all 15 Subjects
Abstract:
... A three-step bio-oil production process involving torrefaction pretreatment (225, 250, or 275 °C at 20 min hold time), pyrolysis (500 °C, two heating rates), and secondary catalytic processing over HZSM-5 (at 400, 450, or 500 °C) was studied to determine how treatments affected byproduct formation and catalyst properties and function. Torrefaction pretreatment significantly reduced average yields ...
DOI:
10.1021/ef301695c

12. Co-gasification of Biomass and Non-biomass Feedstocks: Synergistic and Inhibition Effects of Switchgrass Mixed with Sub-bituminous Coal and Fluid Coke During CO2 Gasification

Author:
Habibi, Rozita; Kopyscinski, Jan; Masnadi, Mohammad S.; Lam, Jill; Grace, John R.; Mims, Charles A.; Hill, Josephine M.
Source:
Energy & Fuels 2013 v.27 no.1 pp. 494-500
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Panicum virgatum; atmospheric pressure; biomass; carbon dioxide; catalysts; catalytic activity; coal; gasification; inorganic matter; minerals; synergism; temperature; thermogravimetry;     Show all 14 Subjects
Abstract:
... Co-gasification of biomass, namely, switchgrass, with coal and fluid coke was performed to investigate the availability of the gasification catalysts to the mixed feedstock, especially alkali and alkaline earth elements, naturally present on switchgrass. Rates of CO₂ gasification of the single and mixed materials were measured at temperatures between 750 and 950 °C and atmospheric pressure by ther ...
DOI:
10.1021/ef301567h

13. Production of Liquid Feedstock from Biomass via Steam Pyrolysis in a Fluidized Bed Reactor

Author:
Kantarelis, Efthymios; Yang, Weihong; Blasiak, Wlodzimierz
Source:
Energy & Fuels 2013 v.27 no.8 pp. 4748-4759
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Picea; biofuels; biomass; carboxylic acids; condensation reactions; fluidized beds; hydrogen; nitrogen; oils; oxygen; pyrolysis; steam; sugars; temperature; water content; wood;     Show all 17 Subjects
Abstract:
... The nature of liquids derived from biomass fast pyrolysis is far from typical oil, and thus, different approaches for bio-oil production and upgrading are needed. In this paper the steam pyrolysis of a pine and spruce wood mixture in a bubbling fluidized bed is investigated. Particularly, the effect of steam to biomass ratio and temperature in relation to products yields and composition has been s ...
DOI:
10.1021/ef400580x

14. Steam–Coal Gasification Using CaO and KOH for in Situ Carbon and Sulfur Capture

Author:
Siefert, Nicholas S.; Shekhawat, Dushyant; Litster, Shawn; Berry, David A.
Source:
Energy & Fuels 2013 v.27 no.8 pp. 4278-4289
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; calcium; calcium carbonate; calcium oxide; calcium sulfate; carbon; carbon dioxide; cement; coal; electricity; gasification; hydrogen; hydrogen sulfide; methane; mixing; potassium hydroxide; sulfur; synthesis gas; temperature;     Show all 19 Subjects
Abstract:
... We present experimental results of coal gasification with and without the addition of calcium oxide and potassium hydroxide as dual-functioning catalyst–capture agents. Using two different coal types and temperatures between 700 and 900 °C, we studied the effect of these catalyst–capture agents on (1) the syngas composition, (2) CO₂ and H₂S capture, and (3) the steam–coal gasification kinetic rate ...
DOI:
10.1021/ef302192p

15. Investigation of the Gasification Performance of Lignite Feedstock and the Injection Design of a Cross-Type Two-Stage Gasifier

Author:
Chyou, Yau-Pin; Chen, Ming-Hong; Luan, Yan-Tsan; Wang, Ting
Source:
Energy & Fuels 2013 v.27 no.6 pp. 3110-3121
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; chemical reactions; electricity; energy; gasification; industry; lignite; mathematical models; nuclear power; power plants; prices; slurries; temperature; thermal cracking; Illinois; North Dakota;     Show all 16 Subjects
Abstract:
... In the last three years, the Institute of Nuclear Energy Research (INER) has been developing the E-GAS gasification numerical model and analyzing the gasification performance by conducting several parametric studies. A preliminary numerical model considering coal particles tracking, two-step volatiles thermal cracking, and nine chemical reactions has been established. In last year’s results, the s ...
DOI:
10.1021/ef400394s

16. Process Balances of Vegetable Oil Hydrogenation and Coprocessing Investigations with Middle-Distillates

Author:
Endisch, Matthias; Kuchling, Thomas; Roscher, Jan
Source:
Energy & Fuels 2013 v.27 no.5 pp. 2628-2636
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Jatropha; alkanes; catalysts; desulfurization; distillates; filtration; fluid mechanics; gas chromatography; hydrogen; hydrogenation; infrared spectroscopy; nuclear magnetic resonance spectroscopy; oxygen; rapeseed oil; sulfur; temperature; vegetable oil;     Show all 18 Subjects
Abstract:
... The hydrogenation of vegetable oil is a promising technology for the production of highly valuable diesel components. Suitable production routes are the hydrogenation on sulfided NiMo catalysts with pure vegetable oil as feedstock or their coprocessing with middle distillates. To obtain the yields of all products for a complete process balance, experimental studies with rapeseed oil and jatropha o ...
DOI:
10.1021/ef400007e

17. Production of Liquid Fuel via Coliquefaction of Coal and Dunaliella tertiolecta in a Sub-/Supercritical Water–Ethanol System

Author:
Yang, Ruili; Chen, Yu; Wu, Yulong; Hua, Derun; Yang, Mingde; Li, Chun; Chen, Zhen; Liu, Ji
Source:
Energy & Fuels 2013 v.27 no.5 pp. 2619-2627
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Dunaliella tertiolecta; Fourier transform infrared spectroscopy; X-ray photoelectron spectroscopy; autoclaves; coal; ethanol; liquefaction; physicochemical properties; scanning electron microscopy; solvents; synergism; temperature;     Show all 13 Subjects
Abstract:
... The current paper presented the coliquefaction of coal and Dunaliella tertiolecta to produce liquid fuel with sub-/supercritical water–ethanol as the reaction medium in a batch autoclave at high temperature and pressure. The effects of the ethanol/water volume ratio, temperature, feedstock/solvent ratio, and reaction time on the liquid fuel yield and conversion were carried out. The optimal liquid ...
DOI:
10.1021/ef4001242

18. Conversion of the Acetone–Butanol–Ethanol (ABE) Mixture to Hydrocarbons by Catalytic Dehydration

Author:
Nahreen, Shaima; Gupta, Ram B.
Source:
Energy & Fuels 2013 v.27 no.4 pp. 2116-2125
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; Clostridium acetobutylicum; acetone; aluminum oxide; biomass; butanol; carbon dioxide; catalysts; cross reaction; energy content; ethanol; fermentation; gases; hydrocarbons; temperature; zeolites;     Show all 16 Subjects
Abstract:
... An acetone–butanol–ethanol (ABE) mixture, containing 62.9 wt % n-butanol, 29.3 wt % acetone, and 7.8 wt % ethanol, can be produced from biomass through the well-established ABE fermentation process using genetically modified Clostridium acetobutylicum. In this work, the catalytic dehydration reactions of the ABE mixture are studied to deoxygenate the mixture. A feed of the ABE mixture was preheate ...
DOI:
10.1021/ef302080n

19. Influence of the Pyrolysis Temperature on Sewage Sludge Product Distribution, Bio-Oil, and Char Properties

Author:
Trinh, Trung Ngoc; Jensen, Peter Arendt; Dam-Johansen, Kim; Knudsen, Niels Ole; Sørensen, Hanne Risbjerg
Source:
Energy & Fuels 2013 v.27 no.3 pp. 1419-1427
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; ash content; biofuels; energy recovery; industrial applications; molecular weight; oils; phosphorus; polymerase chain reaction; pyrolysis; sewage sludge; sewage treatment; solid wastes; temperature; thermal properties; viscosity;     Show all 16 Subjects
Abstract:
... Fast pyrolysis may be used for sewage sludge treatment with the advantages of a significant reduction of solid waste volume and production of a bio-oil that can be used as fuel. A study of the influence of the reaction temperature on sewage sludge pyrolysis has been carried out using a pyrolysis centrifugel reactor (PCR) at 475, 525, 575, and 625 °C. Maxima of both organic oil yield of 41 wt % on ...
DOI:
10.1021/ef301944r

20. Energy Requirement for Lignocellulosic Feedstock Densifications in Relation to Particle Physical Properties, Preheating, and Binding Agents

Author:
Miao, Zewei; Grift, Tony E.; Hansen, Alan C.; Ting, K. C.
Source:
Energy & Fuels 2013 v.27 no.1 pp. 588-595
ISSN:
1520-5029
Subject:
feedstocks,   etc   ; binding agents; biomass; bulk density; byproducts; corn; energy efficiency; ethanol production; lignocellulose; particle size; pelleting; specific energy; temperature; water content;     Show all 14 Subjects
Abstract:
... The low bulk density and low flowability of lignocellulosic biomass feedstock have been regarded widely as major barriers for a sustainable and efficient supply system. Densification of biomass is a viable option to increase the bulk (and inherent energy) density and flowability of feedstock, leading to improved efficiency of the supply system. The energy consumption of feedstock densification is ...
DOI:
10.1021/ef301562k