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Use of thermogravimetry/mass spectrometry analysis to explain the origin of volatiles produced during biomass pyrolysis / Agustín García Barneto in Industrial & engineering chemistry research, Vol. 48 N° 15 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7430–7436 Titre : Use of thermogravimetry/mass spectrometry analysis to explain the origin of volatiles produced during biomass pyrolysis Type de document : texte imprimé Auteurs : Agustín García Barneto, Auteur ; José Ariza Carmona, Auteur ; José E. Martín Alfonso, Auteur Année de publication : 2009 Article en page(s) : pp. 7430–7436 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Thermogravimetry  coupled  to  mass  spectrometry  Pyrolysis Résumé : Pyrolysis of alternative biomasses, which contributes to the recovery of arid soils and does not compete with alimentary biomass, could increase use of biomass as feedstock in energy production facilities. In this sense, in order to optimize this thermal process and gain better insight the origin and evolution of the main produced volatiles, nonisothermal thermogravimetry coupled to mass spectrometry (TG/MS) has been applied for samples of two biomasses [Leucaena Leucocephala (Leucaena) and Chamaecytisus Palmensis (Tagasaste)], which find application as energy crops and contribute to soil restoration. In a first stage, autocatalytic kinetics has been used in order to obtain the mass loss rate profiles (DTG) of each biomass pseudocomponent (hemicellulose, cellulose, lignin, and extractives) during pyrolysis. In a second stage, the experimental mass spectrometry signals of the main volatiles (CO, CO2, and H2O) have been simulated using a linear combination of the previously calculated DTG profiles. The accurate fitting obtained, explains the origin of these volatiles from a simple volatization process, mainly from lignin. In a third stage, in order to simulate the hydrogen signal, it has been necessary to consider the char produced during the volatization process. According to the model, the charring process explains close to 77 wt % of the total hydrogen obtained during pyrolysis. Considering the specific char production of each biomass pseudocomponent, it is possible to measure their individual contributions to hydrogen production: hemicellulose, 27.5; cellulose, 9.7; and lignin, 60.9 wt %, for Leucaena. Taking into account the composition of the samples, the relation between the specific hydrogen productions of the single pseudocomponents (hemicellulose:cellulose:lignin) can be calculated: 3.4:1.0:7.6. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900453w [article] Use of thermogravimetry/mass spectrometry analysis to explain the origin of volatiles produced during biomass pyrolysis [texte imprimé] / Agustín García Barneto, Auteur ; José Ariza Carmona, Auteur ; José E. Martín Alfonso, Auteur . - 2009 . - pp. 7430–7436. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7430–7436 Mots-clés : Thermogravimetry  coupled  to  mass  spectrometry  Pyrolysis Résumé : Pyrolysis of alternative biomasses, which contributes to the recovery of arid soils and does not compete with alimentary biomass, could increase use of biomass as feedstock in energy production facilities. In this sense, in order to optimize this thermal process and gain better insight the origin and evolution of the main produced volatiles, nonisothermal thermogravimetry coupled to mass spectrometry (TG/MS) has been applied for samples of two biomasses [Leucaena Leucocephala (Leucaena) and Chamaecytisus Palmensis (Tagasaste)], which find application as energy crops and contribute to soil restoration. In a first stage, autocatalytic kinetics has been used in order to obtain the mass loss rate profiles (DTG) of each biomass pseudocomponent (hemicellulose, cellulose, lignin, and extractives) during pyrolysis. In a second stage, the experimental mass spectrometry signals of the main volatiles (CO, CO2, and H2O) have been simulated using a linear combination of the previously calculated DTG profiles. The accurate fitting obtained, explains the origin of these volatiles from a simple volatization process, mainly from lignin. In a third stage, in order to simulate the hydrogen signal, it has been necessary to consider the char produced during the volatization process. According to the model, the charring process explains close to 77 wt % of the total hydrogen obtained during pyrolysis. Considering the specific char production of each biomass pseudocomponent, it is possible to measure their individual contributions to hydrogen production: hemicellulose, 27.5; cellulose, 9.7; and lignin, 60.9 wt %, for Leucaena. Taking into account the composition of the samples, the relation between the specific hydrogen productions of the single pseudocomponents (hemicellulose:cellulose:lignin) can be calculated: 3.4:1.0:7.6. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900453w