Research on cellulose pyrolysis kinetics

Despite intensive studies led to on cellulose pyrolysis kinetics, the still remaining controversies on the apparent kinetics different explanations for the cellulose pyrolysis mechanism. The reaction kinetics and pyrolysis mechanism were studied. The cellulose pyrolysis process has five distinct phases as temperature increases. The third phase in which the huge amount of volatile is released causing cellulose weight decrease, plays a main role in the whole process. The TG curve moves toward the direction of higher temperature as the heating rate increases, because of the increase in thermal lag. Furthermore, high heating rate promotes volatile production while inhibits char formation. The apparent activation energy and pre-exponential on the third phase of the cellulose pyrolysis process were calculated by differential quotient method. Using 600 K as break point, the activation energy in the lower temperature zone was calculated to be 267 kJ/mol, but only 174 kJ/mol in the higher temperature zone. Cellulose pyrolysis is a complicated process controlled by both kinetics and heat mass transfer. The various kinetic parameters of cellulose pyrolysis reported by others were mainly due to the different experimental conditions and heat mass transfer processes.