Kinetic study of regeneration

Oxygen (O2) diffuses through the cinder layer, where no reaction takes place, reaches the interface, oxidizes carbon and then CO2 just formed diffuses through the opposite direction crossing the cinder layer. Considering a carbon particle radius Ho and interface radius we obtain for each mol of O2 (reactant A) the diffusion rate  

The molar balance on a surface element Anr between r and r + dr, where no reaction takes place will be  

Therefore, the reactant A molar flow (Na) at the interface will be  

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