Heat and Mass Change Behavior and Kinetics of Quercus acutissima Wood Pyrolysis
In order to well know the pyrolysis characteristics of Quercus acutissima wood,the weightlessness mechanism and thermal behavior of pyrolysis process were analyzed by thermogravimetric analysis,the apparent activation energy of pyrolysis process was calculated through Flynn-Wall-Ozawa(FWO)model and Kissinger-Akahira-Sunose(KAS)model,and the most probable mechanism function was obtained based on Malek method.The results show that the pyrolysis processes can be divided into four stages:dry,preheating,volatile fraction removal and carbonization.The weight loss in the volatile fraction removal stage accounts for 71.24％of the weight loss of total pyrolysis process.The pyrolysis process of quercus acutissima includes both endothermic and exothermic reactions.With the increase of heat rate,TG curves and DTG curves move towards high temperature.The apparent activation energies obtained by FWO model and that of KAS model range from 226.79-258.17 kJ/mol and 229.22-260.8 kJ/mol,respectively,while the trend of the apparent activation energies from above two models are similar.Coefficients of determination are above 0.94.The result from the Malek method shows that the three-dimensional diffusion model(Jander equation)is dominant when the conversion is lower than 0.5,and nuclei formation model(Avrami-Erofeev equation,n=3/2)is dominant when the conversion is higher than 0.5.
quercus acutissima woodweightlessness behaviorthermal behaviormost probable mechanism function
国家科技期刊平台
NSTL
万方数据
