Analysis of cross-linking behavior during pyrolysis of cellulose for elucidating reaction pathway
Publication details: nov./dic. 2009Description: 8 p. ; 5765-5772 In: Energy & fuels 23Summary: Transcripción del resumen del autor. The analyses of structure change during pyrolysis of cellulose at different heating rates were investigated to clarify the existent behavior of the cross-linking reaction. For structural analyses of cellulose precursors, FTIR spectra and XRD patterns confirmed that the dehydration reaction to produce water and cross-liked precursor simultaneously occurred with the glycosidic reaction to produce tar during pyrolysis. On the basis of the assumptions that hydroxyl groups in cellulose converted to water, a new parameter index, so-called the degree of dehydration during pyrolysis, Xp, including its distribution in char (Xc) and tar (Xt), was determined. For the cross-linking analyses at low heating rate, cross-linking reaction may occur until approximately 360 °C where Xc reached its maximum, while the cross-linked tar seems to be released above 360 °C. For tar analyses, cross-linked dimer can be observed for slow pyrolysis, whereas tar products obtained by flash pyrolysis showed relatively higher yield in cellobiosan with no cross-linked volatiles. Finally, based on previous kinetic models, the modified pathway of cellulose pyrolysis was proposed by considering the proposed parameter related to the dehydration.| Current library | Status | Barcode | |
|---|---|---|---|
| Biblioteca Alejandro Angel Bulgheroni | Not for loan | 200045670 |
Transcripción del resumen del autor. The analyses of structure change during pyrolysis of cellulose at different heating rates were investigated to clarify the existent behavior of the cross-linking reaction. For structural analyses of cellulose precursors, FTIR spectra and XRD patterns confirmed that the dehydration reaction to produce water and cross-liked precursor simultaneously occurred with the glycosidic reaction to produce tar during pyrolysis. On the basis of the assumptions that hydroxyl groups in cellulose converted to water, a new parameter index, so-called the degree of dehydration during pyrolysis, Xp, including its distribution in char (Xc) and tar (Xt), was determined. For the cross-linking analyses at low heating rate, cross-linking reaction may occur until approximately 360 °C where Xc reached its maximum, while the cross-linked tar seems to be released above 360 °C. For tar analyses, cross-linked dimer can be observed for slow pyrolysis, whereas tar products obtained by flash pyrolysis showed relatively higher yield in cellobiosan with no cross-linked volatiles. Finally, based on previous kinetic models, the modified pathway of cellulose pyrolysis was proposed by considering the proposed parameter related to the dehydration.
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