关键词:

等转化率法, 活化能, model free, Coats-Redfern

Abstract:

TG analysis was used to investigate the thermal decomposition of flax fibers which are a potential gasification feedstock.10 mg flax shive samples with the particles between 0.60 and 0.85 mm was linearly heated to 550℃ at heating rates of 10, 20, 30, 50 K·min^-1,respectively, under high-purity nitrogen. Coats-Redfern model fitting method and model-free methods include Kissinger method and three isoconversional methods (Friedman, Flynn-wall-Ozawa, Vyazovkin and Wight methods) were used to estimate the apparent activation energy of the fax fibers.With the three isoconversional methods,it can be concluded that the activation energy increases with increasing conversion.The four model free methods indicated activation energies in the range of 155—175 kJ·mol^-1.Activation energies by Coats-Redfern model fitting method was about 175 kJ·mol^-1,close to the values by model free method.These activation energy values provide the basic data for the thermo-chemical utilization of the flax fibers.

Key words:

等转化率法, 活化能, model free, Coats-Redfern