Pyrolytic and kinetic characteristics of Platycodon grandiflorum peel and its cellulose extract

The pyrolytic and kinetic characteristics of a biomass waste material, namely Platycodon grandiflorum A. DC (P. G.) peel and its cellulose extract were studied at heating rates of 10, 30 and 50 °C/min under a nitrogen flow atmosphere. The most probable mechanism function and activation energy pre-exponential factors were calculated by using the Popescu, FWO and KAS methods. The three stages appeared during pyrolysis include: moisture evaporation, primary devolatilization and residual decomposition. Significant differences in the average activation energy, thermal stability, final residuals and reaction rates of the P. G. peel and its cellulose extract were observed. Stage II of the P. G. peel and its cellulose extract could be described by the function Avrami-Erofeev [-ln(1-α)](3) and the function chemical reaction (1-α)(-0.5), respectively. The average activation energy of P. G. peel and its cellulose extract were 157 and 196 kJ/mol, respectively. Kinetic compensation effects of the pre-exponential factors and activation energy were also observed.