Analysis of Cross-Linking Behavior during Pyrolysis of Cellulose for Elucidating Reaction Pathway

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, X-p, including its distribution in char (X-c) and tar (X-t), was determined. For the cross-linking analyses at low healing rate, cross-linking reaction may occur until approximately 360 degrees C where X-c reached its maximum,while the cross-linked tar seems to be released above 360 degrees C. For tar analyses, cross-linked dinner 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.