A kinetic model of nano‐CaO reactions with CO2 in a sorption complex catalyst

Abstract

AbstractThis article describes the reactive kinetics of nano‐CaO with CO2 in a sorption complex catalyst. Based on an observation of nano‐CaO reaction with CO2 has a fast surface reaction regime and followed by a slow diffusion‐controlled regime, a criterion has been proposed to divide the fast surface reaction regime and the slow diffusion‐controlled reaction regime. The kinetics of the fast surface reaction was studied, and a new ion reaction mechanism was proposed. A surface reaction‐controlled kinetic model with a Boltzmann equation, X = Xu−Xu/[1+exp((t−t0)k/Xu)], was developed. Experiments using nano‐CaO to react with CO2 in a fast surface reaction regime within a sorption complex catalyst were performed using thermogravimetric analysis at 773–873 K under a N2 atmosphere with 0.010–0.020 MPa CO2. The activation energy of the kinetic model for carbonation is 30.2 kJ/mol, and the average relative deviation of the sorption ratio is less than 9.8%. © 2011 American Institute of Chemical Engineers AIChE J, 2012