On Thermal Stability and Chemical Kinetics of Waste Newspaper by Thermogravimetric and Pyrolysis Analysis

Abstract

The thermogravimetric analysis is studied to investigate the thermal stability and the chemical kinetics of waste newspaper. The thermal degradation and the kinetic parameters (Order of reaction, activation energy and pre-exponential factor) are determined at different heating rate by using TG/DTA data. The heating rates used in this study are 5, 10 and 20 K/min respectively. The decomposition results could be modeled by an Arrhenius equation. The least square technique is used for determining kinetic parameters. Depending on the heating rate, the activation energy and the order of reaction vary from 8.15 to 23.42 kJ/mol and 0.56 to 0.79 for newspaper (moisture free basis). Next attempt is to use waste newspaper as a raw material for converting it into bio-oil via pyrolysis. The yield of bio-oil is increasing with increasing the pyrolysis temperature. The average maximum yield of bio-oil 39% is obtained at the pyrolysis temperature of 500°C. Pyrolysis gases have also been analyzed in a gas chromatography to measure the concentration of hydrogen gas at increasing temperatures and also checked the effect of heat keeping time, defined as the time with a constant temperature in the reactor to the gas yields. The pyrolysis temperatures 500, 700, 900 and 1000°C and heat keeping time 0, 30 and 60 minutes are applied in this study. Maximum about 53 vol% of H2 is observed by applying the temperature of 900°C and heat keeping time of 60 minutes.