AbstractA new synthetic regenerable sorbent was developed as an alternative to limestone and dolomite for regenerative sulfur capture in fluidized bed combustion (FBCof coal. The sorbent consists of CaO (8‐9 wt%) on a spherical 3 mm diameter γ‐Al2O3support. A shrinking unreacted core model (SURE2) is proposed to describe the sulfation process. Experiments have been carried out in a 12 mm internal diameter fixed bed reactor, a 0.05 mIDfluidized bed reactor and a thermobalance. The results obtained for all three reactors are in good agreement with the predictions of theSURE2 m