Effect of pyrolysis temperature on bamboo char combustion: Reactivity, kinetics and thermodynamics

The combustion behavior of bamboo char (BC) under pyrolysis temperatures (673-1173 K) is studied by non-isothermal thermogravimetric analysis. Results show pyrolysis temperature lowers the ignition and burnout performance of biochar. The combustion reactivity firstly increases and then decreases, and BC-973 is the best. Kinetic models of Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose calculate the activation energy (E), integral master-plots method determines reaction equation is the reaction order that when the heating rate is less than 12 K/min, reaction orders firstly decrease and then increase with pyrolysis temperature, and reaction orders are around 1 for 24 K/min. Thermodynamic parameters (Delta H, Delta S and Delta G) are calculated, and the prediction equations about E, Delta H, Delta S and Delta G are proposed. Meanwhile, activation energy under first order reaction and experimental equation are compared, results show that average E values under first order reaction are greater in 773-973 K, and the rest of pyrolysis temperatures are adverse. (C) 2020 Elsevier Ltd. All rights reserved.