Abstract: The physicochemical properties of Miscanthus sinensis Andersson pyrolysis char was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy and low temperature nitrogen adsorption. The CO₂ gasification reaction mechanism of M. sinensis pyrolysis char was studied by a non-isothermal thermogravimetry method along with Master-plot method. The results showed that the organics of pyrolysis char decreases with the increment of temperature. Pyrolysis process was beneficial to the formation of pore structure and improvement of the specific surface area and pore volume. The maximum microporisty of 600℃ pyrolysis char (MPC600) was 86.73%. With the increasing of pyrolysis char preparation temperature and gasification heating rate, the maximum conversion rate temperature of pyrolysis char gasification reaction were shifted to the high temperature side. The gasification kinetic parameters of pyrolysis chars were calculated by Ozawa method. The average activation energy of pyrolysis chars were 171.87, 181.20 and 184.45 kJ/mol at 400, 600 and 800℃, respectively. The activation energy was independent of the conversion rate and the reaction can be described by a single kinetic mechanism function. The Master-plot method was used to determine the mechanism function of the kinetic model. The gasification kinetics of pyrolysis char was consistent with the 1D phase boundary reaction (R₁) mechanisms.

Key words: preparation condition, CO₂ gasification reaction characteristics, Master-plot method