Sorption of SO 2 and NO from simulated flue gas over rice husk ash (RHA)/CaO/CeO 2 sorbent: Evaluation of deactivation kinetic parameters

Abstract

In this study, the kinetic parameters of rice husk ash (RHA)/CaO/CeO 2 sorbent for SO 2 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 ( k 0) and deactivation rate constant ( k d) for SO 2/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 °C. The activation energy and frequency factor for the SO 2 sorption were found to be 18.0 kJ/mol and 7.37 × 10 5 cm 3/(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 × 10 4 cm 3/(g min), respectively. The deactivation kinetic model was found to give a very good agreement with the experimental data of the SO 2/NO sorptions.