1988
Journal Articles
Bilbao, Rafael; Millera, Ángela; Arauzo, Jesús
Product distribution in the flash pyrolysis of lignocellulosic materials in a fluidized bed Journal Article
In: Fuel, vol. 67, no. 11, pp. 1586–1588, 1988, ISSN: 00162361.
@article{Bilbao1988a,
title = {Product distribution in the flash pyrolysis of lignocellulosic materials in a fluidized bed},
author = {Rafael Bilbao and Ángela Millera and Jesús Arauzo},
doi = {10.1016/0016-2361(88)90082-8},
issn = {00162361},
year = {1988},
date = {1988-11-01},
journal = {Fuel},
volume = {67},
number = {11},
pages = {1586--1588},
publisher = {Elsevier},
abstract = {Knowledge of the flash pyrolysis of lignocellulosic materials is of great importance because it constitutes the first step of several thermochemical processes. This work is concerned with the study of the products obtained when the pyrolysis of lignocellulosic materials is carried out in a fluidized bed reactor. Two different feeds have been used, namely, wheat straw and pine sawdust. The proportions of gas, liquid and solids in the product as well as the composition of the exit gas have been obtained for different operating conditions. textcopyright 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Knowledge of the flash pyrolysis of lignocellulosic materials is of great importance because it constitutes the first step of several thermochemical processes. This work is concerned with the study of the products obtained when the pyrolysis of lignocellulosic materials is carried out in a fluidized bed reactor. Two different feeds have been used, namely, wheat straw and pine sawdust. The proportions of gas, liquid and solids in the product as well as the composition of the exit gas have been obtained for different operating conditions. textcopyright 1988.
1987
Journal Articles
Bilbao, Rafael; Arauzo, Jesús; Millera, Ángela
Kinetics of thermal decomposition of cellulose. Part I. Influence of experimental conditions Journal Article
In: Thermochimica Acta, vol. 120, no. C, pp. 121–131, 1987, ISSN: 00406031.
@article{Bilbao1987,
title = {Kinetics of thermal decomposition of cellulose. Part I. Influence of experimental conditions},
author = {Rafael Bilbao and Jesús Arauzo and Ángela Millera},
doi = {10.1016/0040-6031(87)80211-3},
issn = {00406031},
year = {1987},
date = {1987-10-01},
journal = {Thermochimica Acta},
volume = {120},
number = {C},
pages = {121--131},
publisher = {Elsevier},
abstract = {The kinetics of weight loss in the thermal decomposition of cellulose have been determined by means of isothermal and dynamic experiments carried out under various conditions. Values for the pyrolyzable fraction, reaction order and kinetic constant have been obtained from isothermal experiments, while the important influence of the rate of heating of the system as well as the percentages of pyrolyzed solids at T ≤ 150°C have been observed from the dynamic experiments. textcopyright 1987.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The kinetics of weight loss in the thermal decomposition of cellulose have been determined by means of isothermal and dynamic experiments carried out under various conditions. Values for the pyrolyzable fraction, reaction order and kinetic constant have been obtained from isothermal experiments, while the important influence of the rate of heating of the system as well as the percentages of pyrolyzed solids at T ≤ 150°C have been observed from the dynamic experiments. textcopyright 1987.
Bilbao, Rafael; Arauzo, Jesús; Millera, Ángela
Kinetics of thermal decomposition of cellulose. Part II. Temperature differences between gas and solid at high heating rates Journal Article
In: Thermochimica Acta, vol. 120, no. C, pp. 133–141, 1987, ISSN: 00406031.
@article{Bilbao1987a,
title = {Kinetics of thermal decomposition of cellulose. Part II. Temperature differences between gas and solid at high heating rates},
author = {Rafael Bilbao and Jesús Arauzo and Ángela Millera},
doi = {10.1016/0040-6031(87)80212-5},
issn = {00406031},
year = {1987},
date = {1987-10-01},
journal = {Thermochimica Acta},
volume = {120},
number = {C},
pages = {133--141},
publisher = {Elsevier},
abstract = {The use of high heating rates when studying the thermal decomposition kinetics of cellulose gives rise to a gap between the solid temperature and the thermogravimetric system temperature. A model is proposed which accounts for this temperature gap and permits the calculation of the actual solid temperature. The results for various heating rates are fitted using the same kinetic equation. textcopyright 1987.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The use of high heating rates when studying the thermal decomposition kinetics of cellulose gives rise to a gap between the solid temperature and the thermogravimetric system temperature. A model is proposed which accounts for this temperature gap and permits the calculation of the actual solid temperature. The results for various heating rates are fitted using the same kinetic equation. textcopyright 1987.
0000
Journal Articles
Tran, Luc Sy; Carstensen, Hans-Heinrich; Foo, Kae Ken; Lamoureux, Nathalie; Gosselin, Sylvie; Gasnot, Laurent; El-Bakali, Abderrahman; Desgroux, Pascale
Experimental and modeling study of the high-temperature combustion chemistry of tetrahydrofurfuryl alcohol Journal Article
In: Proceedings of the Combustion Institute, vol. 38, no. 1, pp. 631-640, 0000, ISSN: 15407489.
@article{Tran2020,
title = {Experimental and modeling study of the high-temperature combustion chemistry of tetrahydrofurfuryl alcohol},
author = {Luc Sy Tran and Hans-Heinrich Carstensen and Kae Ken Foo and Nathalie Lamoureux and Sylvie Gosselin and Laurent Gasnot and Abderrahman El-Bakali and Pascale Desgroux},
doi = {10.1016/j.proci.2020.07.057},
issn = {15407489},
urldate = {2020-09-01},
journal = {Proceedings of the Combustion Institute},
volume = {38},
number = {1},
pages = {631-640},
publisher = {Elsevier Ltd},
abstract = {Lignocellulosic tetrahydrofuranic (THF) biofuels have been identified as promising fuel candidates for spark-ignition (SI) engines. To support the potential use as transportation biofuels, fundamental studies of their combustion and emission behavior are highly important. In the present study, the high-temperature (HT) combustion chemistry of tetrahydrofurfuryl alcohol (THFA), a THF based biofuel, was investigated using a comprehensive experimental and numerical approach. Representative chemical species profiles in a stoichiometric premixed methane flame doped with $sim$20% (molar) THFA at 5.3 kPa were measured using online gas chromatography. The flame temperature was obtained by NO laser-induced fluorescence (LIF) thermometry. More than 40 chemical products were identified and quantified. Many of them such as ethylene, formaldehyde, acrolein, allyl alcohol, 2,3-dihydrofuran, 3,4-dihydropyran, 4-pentenal, and tetrahydrofuran-2-carbaldehyde are fuel-specific decomposition products formed in rather high concentrations. In the numerical part, as a complement to kinetic modeling, high-level theoretical calculations were performed to identify plausible reaction pathways that lead to the observed products. Furthermore, the rate coefficients of important reactions and the thermochemical properties of the related species were calculated. A detailed kinetic model for high-temperature combustion of THFA was developed, which reasonably predicts the experimental data. Subsequent rate analysis showed that THFA is mainly consumed by H-abstraction reactions yielding several fuel radicals that in turn undergo either $beta$-scission reactions or intramolecular radical addition that effectively leads to ring enlargement. The importance of specific reaction channels generally correlates with bond dissociation energies. Along THFA reaction routes, the derived species with cis configuration were found to be thermodynamically more stable than their corresponding trans configuration, which differs from usual observations for hydrocarbons.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Lignocellulosic tetrahydrofuranic (THF) biofuels have been identified as promising fuel candidates for spark-ignition (SI) engines. To support the potential use as transportation biofuels, fundamental studies of their combustion and emission behavior are highly important. In the present study, the high-temperature (HT) combustion chemistry of tetrahydrofurfuryl alcohol (THFA), a THF based biofuel, was investigated using a comprehensive experimental and numerical approach. Representative chemical species profiles in a stoichiometric premixed methane flame doped with $sim$20% (molar) THFA at 5.3 kPa were measured using online gas chromatography. The flame temperature was obtained by NO laser-induced fluorescence (LIF) thermometry. More than 40 chemical products were identified and quantified. Many of them such as ethylene, formaldehyde, acrolein, allyl alcohol, 2,3-dihydrofuran, 3,4-dihydropyran, 4-pentenal, and tetrahydrofuran-2-carbaldehyde are fuel-specific decomposition products formed in rather high concentrations. In the numerical part, as a complement to kinetic modeling, high-level theoretical calculations were performed to identify plausible reaction pathways that lead to the observed products. Furthermore, the rate coefficients of important reactions and the thermochemical properties of the related species were calculated. A detailed kinetic model for high-temperature combustion of THFA was developed, which reasonably predicts the experimental data. Subsequent rate analysis showed that THFA is mainly consumed by H-abstraction reactions yielding several fuel radicals that in turn undergo either $beta$-scission reactions or intramolecular radical addition that effectively leads to ring enlargement. The importance of specific reaction channels generally correlates with bond dissociation energies. Along THFA reaction routes, the derived species with cis configuration were found to be thermodynamically more stable than their corresponding trans configuration, which differs from usual observations for hydrocarbons.
Mergulhão, Carolina S; Carstensen, Hans-Heinrich; Song, Hwasup; Wagnon, Scott W; Pitz, William J; Vanhove, Guillaume
Probing the antiknock effect of anisole through an ignition, speciation and modeling study of its blends with isooctane Journal Article
In: Proceedings of the Combustion Institute, vol. 38, no. 1, pp. 739-748, 0000, ISSN: 15407489.
@article{Mergulhao2020,
title = {Probing the antiknock effect of anisole through an ignition, speciation and modeling study of its blends with isooctane},
author = {Carolina S Mergulhão and Hans-Heinrich Carstensen and Hwasup Song and Scott W Wagnon and William J Pitz and Guillaume Vanhove},
doi = {10.1016/j.proci.2020.08.013},
issn = {15407489},
urldate = {2020-10-01},
journal = {Proceedings of the Combustion Institute},
volume = {38},
number = {1},
pages = {739-748},
publisher = {Elsevier Ltd},
abstract = {In order to unravel the reaction pathways relevant to anisole co-oxidation within a fuel blend, a detailed study of isooctane/anisole blends was performed with the ULille RCM. Ignition delays as well as mole fraction profiles were measured during a two-stage ignition delay using sampling and GC techniques. These results are used to validate a kinetic model developed from ab initio calculations for the most relevant rate constants which included H-atom abstraction reactions from anisole, and reactions on the potential energy surfaces of methoxyphenyl + O2 and anisyl + O2. Pressure dependent rate constants were computed for the methoxyphenyl + O2 and anisyl + O2 reactive systems using master equation code analysis. The new kinetic model shows good agreement with the experimental data. Dual brute-force sensitivity analysis was performed, on both first- and second-stages of ignition, allowing the identification of the most important reactions in the prediction of both ignition delays. It was observed that while pure anisole does not show NTC behavior, a 60/40 isooctane/anisole blend displays such behavior, as well as two-stage ignition. This suggests anisole addition may not be as beneficial to knock resistance as expected from its high octane number. The kinetic modeling results demonstrate the importance of H-abstraction reactions both from the methoxy group and from the aryl ring in ortho-position and the addition of the resultant radicals to O2, mostly leading to the formation of polar or non-aromatic products.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to unravel the reaction pathways relevant to anisole co-oxidation within a fuel blend, a detailed study of isooctane/anisole blends was performed with the ULille RCM. Ignition delays as well as mole fraction profiles were measured during a two-stage ignition delay using sampling and GC techniques. These results are used to validate a kinetic model developed from ab initio calculations for the most relevant rate constants which included H-atom abstraction reactions from anisole, and reactions on the potential energy surfaces of methoxyphenyl + O2 and anisyl + O2. Pressure dependent rate constants were computed for the methoxyphenyl + O2 and anisyl + O2 reactive systems using master equation code analysis. The new kinetic model shows good agreement with the experimental data. Dual brute-force sensitivity analysis was performed, on both first- and second-stages of ignition, allowing the identification of the most important reactions in the prediction of both ignition delays. It was observed that while pure anisole does not show NTC behavior, a 60/40 isooctane/anisole blend displays such behavior, as well as two-stage ignition. This suggests anisole addition may not be as beneficial to knock resistance as expected from its high octane number. The kinetic modeling results demonstrate the importance of H-abstraction reactions both from the methoxy group and from the aryl ring in ortho-position and the addition of the resultant radicals to O2, mostly leading to the formation of polar or non-aromatic products.