Pyrolytic kinetics of cellulose and hemicellulose fractions isolated from Mucuna sempervirens Hemsl.

Pyrolytic kinetics of level 4 cellulose and hemicellulose isolated by alkaline hydrogen peroxide from Mucuna sempervirens fibers via fractional separation and degreasing were studied,and the initial decomposition temperature,maximum decomposition,final decomposition of level 4 cellulose and hemicellulose were determined by thermal gravimetry(TG).The thermal decomposition experienced five phases in the following order: ice crystals melt,water endothermic evaporation,fusing,thermal pyrolysis,and final hard coke thermolysis when the temperature ranging from-50 ℃ to 550 ℃,as indicated by differential scanning calorimetry(DSC).The onset temperatures,peak temperatures,end temperatures and endothermic enthalpies of the fusing and thermal pyrolysis endothermic peak were also measured.The Kissinger equation was successfully applied to describe the thermal decomposition process of level 4 celluloses and hemicelluloses,and their kinetic parameters of apparent activation and reaction order were obtained.