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

Abstract

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 (ΔH, ΔS and ΔG) are calculated, and the prediction equations about E, ΔH, ΔS and ΔG 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.