Sorption of SO2 and NO from simulated flue gas over rice husk ash (RHA)/CaO/CeO2 sorbent: Evaluation of deactivation kinetic parameters

In this study, the kinetic parameters of rice husk ash (RHA)/CaO/CeO2 sorbent for SO2 and NO sorptions were investigated in a laboratory-scale stainless steel fixed-bed reactor. Data experiments were obtained from our previous results and additional independent experiments were carried out at different conditions. The initial sorption rate constant (k0) and deactivation rate constant (kd) for SO2/NO sorptions were obtained from the nonlinear regression analysis of the experimental breakthrough data using deactivation kinetic model. Both the initial sorption rate constants and deactivation rate constants increased with increasing temperature, except at operating temperature of 170 oC. The activation energy and frequency factor for the SO2 sorption were found to be 18.0 kJ/mol and 7.37 x 105 cm3/(g min), respectively. Whereas the activation energy and frequency factor for the NO sorption, were estimated to be 5.64 kJ/mol and 2.19 x 104 cm3/(g min), respectively. The deactivation kinetic model was found to give a very good agreement with the experimental data of the SO2/NO sorptions.