Regenerable MgO-based sorbent for high temperature CO2 removal from syngas: 2. Two-zone variable diffusivity shrinking core model with expanding product layer

► A new model is introduced to describe the gas/solid carbonation reaction. ► The model can describe the expanding product layer and two distinct reactive zones. ► The model predictions are very similar to those provided by expanding grain model. ► The model provides an explicit reaction rate expression suitable for CFD applications.