Influence of torrefaction on intrinsic bioconstituents of cotton stalk: TG-insights

This is the first article presenting the detection of discrete and stratified nature of fringes in the lignin-related segment of the activation energy profile of a biomaterial. The torrefied biomaterial made from the cotton stalk was evaluated for intrinsic physico-chemical transformations in comparison with the raw cotton stalk. The intrinsic hemicellulose and cellulose components disappeared due to torrefaction process. Lignin was substantially noticed in torrefied biomaterial. Transitions of activation energy levels from raw to torrefied biomaterial were critically discussed and explained on the basis of Coats-Redfern kinetics. The patterned segregation of activation energy levels in the lignin degradation region, creating fringes like formations in activation energy profile, was noticed distinctly in the case of the torrefied biomaterial. These fringes were supposed to originate due to thermal stresses imposed on a biomaterial during the torrefaction process.