Kinetics, Thermodynamics, and Volatile Products of Camphorwood Pyrolysis in Inert Atmosphere.

ABSTRACT

The kinetics, thermodynamics, and volatile products of camphorwood pyrolysis were investigated via thermogravimetry coupled with Fourier transform infrared (FTIR) spectroscopy at multiple heating rates. The kinetic triplets and thermodynamic parameters were estimated via model free combined with the model-fitting approach. The results showed that the pyrolysis of camphorwood in the conversion rate range from 0 to 0.85 might be considered as one-step process. The mean value of the activation energy and pre-exponential factor was 192.63 kJ/mol and 2.38 × 1013 s-1, respectively. The pyrolysis process (0 ≤ α ≤ 0.85) can be described by the three-dimensional diffusion model g(α) = [(1-α)-1/3 - 1]2. Furthermore, the predicted curves of the conversion rate α showed good agreement with the experimental curves. The values of ΔH, ΔG, and ΔS varied little with α and remained positive. In addition, the major gas products released from the camphorwood waste pyrolysis were H2O, methane, CO2, CO, C=O, O-H, C-O-C, and NH3, whose concentration in the order from highest to lowest was C=O > CO2 > O-H > H2O > methane > NH3 > C-O-C > CO. The main conclusions in the present study can provide guidance for the design and optimization of industrial reactor and selection of target biofuels or chemical raw materials.