Non-isothermal kinetics of biomass waste pyrolysis by TG-MS/DSC

Abstract

The non-isothermal kinetics and pyrolysis characteristics of biomass waste including camphor wood (CW), pure glycerol (PG) and a blend (1:1 mass ratio) (PG-CW) were studied by coupling TG-MS/DSC techniques. The samples were heated from ambient temperature to 700 °C at different heating rates (10, 15, 20 and 25 °C/min) in a nitrogen atmosphere. The mass loss during pyrolysis and the evolution of gas products were studied. The improved Coats-Redfern method was used to obtain non-isothermal kinetic parameters for samples pyrolysis, and the activation energies and the pre-exponential factors were estimated iteratively by regression to improve their accuracy. PG had only one main pyrolysis phase, while CW had two main pyrolysis phases. The results showed that adding PG into CW reduced the residue and increased the amount of gas released after co-pyrolysis. The non-isothermal kinetic model based on the improved iterative Coats-Redfern method entirely fitted the pyrolysis phases of CW, PG, and PG-CW. The suitable models for the second, third, and fourth phases of blend were nucleation, nucleation, and one-dimensional diffusion, respectively. Activation energy values for the three phases were 67.47–82.48, 81.13–104.43 and 145.45–204.86 kJ/mol, respectively. The addition of PG promoted the pyrolysis process of CW.