M.A. Sokoto, T. Bhaskar
Pyrolysis kinetics of castor seed de-oiled cake (Ricinus communis) using thermogravimetric technique was studied. The decomposition of the cake was carried out in a nitrogen atmosphere with a flow rate of 100 ml min-1 from ambient temperature to 900 ºC. The results of the thermal profile showed moisture removal and devolatilization stages, with maximum decomposition of the cake occurring at temperatures of 200-400 ºC. The kinetic parameters, such as apparent activation energy, pre-exponential factor, and order of reaction, were determined using Friedman (FD), Kissinger-Akahira-Sunose (KAS), and Flynn-Wall-Ozawa (FWO) kinetic models. The average apparent activation energy values of 124.61, 126.95, and 129.80 kJ/mol were calculated from the slopes of the respective models. The apparent activation energy values obtained depend on conversion, which is evidence of a multi-step kinetic process during the pyrolytic decomposition of the cake. The kinetic data would be of immense benefit to model, design, and develop suitable thermo-chemical systems for the usage of this biomass material.