MODELING OF THE INTERACTION OF NITROGEN-DIOXIDE WITH ACTIVATED CARBON.2. KINETICS OF REACTION WITH PORE EVOLUTION

Adsorption of nitrogen dioxide on activated carbon is found to be foll owed by reaction with the carbon surface at temperatures higher than 3 73 K. The dynamics of the nitrogen dioxide reaction with the carbon ar e measured gravimetrically over the temperature range 423-623 K. At sm all particle sizes (0.014 cm radius) the overall gasification kinetics are controlled by the surface reaction step, and are first order in n itrogen dioxide concentration. Using the random pore model to describe the evolution of reaction surface with porosity, the experimental dat a are fitted by a kinetic control gasification model, giving an activa tion energy of 86.2 kJ/mole.