Global kinetic constants for thermal oxidative degradation of a cellulosic paper

Abstract

Values of global kinetic constants for pyrolysis, thermal oxidative degradation, and char oxidation of a cellulosic paper were determined by a derivative thermal gravimetric study. The study was conducted at heating rates of 0.5, 1, 1.5, 3, and 5°C/min in ambient atmospheres of nitrogen, 0.28%, 1.08%, 5.2% oxygen concentrations, and air. Sample weight loss rate, concentrations of CO, CO 2, and H 2O in the degradation products, and oxygen consumption were continuously measured during the experiment. Values of activation energy, pre-exponential factor, orders of reaction, and yields of CO, CO 2, H 2O, total hydrocarbons, and char for each degradation reaction were derived from the results. Heat of reaction for each reaction was determined by differential scanning calorimetry. A comparison of the calculated CO, CO 2, H 2O, total hydrocarbons, sample weight loss rate, and oxygen consumption was made with the measured results using the derived kinetic constants and accuracy of the values of kinetic constants was discussed.