An In-Situ Thermogravimetric Study of Pyrolysis of Rice Hull with Alkali Catalyst of CaCO₃

Pyrolysis of rice hull (RH) with the presence of CaCO₃ catalyst was carried out in this study to understand the effect of alkali catalyst in the thermal degradation behaviour and evaluate the kinetic parameter of rice hull for bio-oil or syngas production. Five different heating rates of the pyrolysis experiments at 10, 20, 30, 50, and 100 Kmin⁻¹ were carried out in thermogravimetric analysis (TGA) equipment. Model fitting kinetic Coats Redfern integral method was applied in this study to estimate the activation energy (EA) and pre-exponential (A) value of catalytic pyrolysis in RH. The results showed that the maximum degradation increased from 6.69 to 52.67 wt% min⁻¹ as heating rates increases from 10 to 100 Kmin⁻¹. Besides that, the EA of the catalytic pyrolysis for RH using CaCO₃ catalyst 60.86 kJmol⁻¹ which is lower than other similar pyrolysis reaction reported in literature i.e. 77.4 kJ/mol. Meanwhile, the A value for the catalytic pyrolysis for RH using CaCO₃ catalyst was 4.68×10¹⁰ min⁻¹ which is significantly higher than 1.1×10⁶ min⁻¹ as reported in literature for non-catalytic pyrolysis of rice husk. (paper)