In the present study, two Greek limestones from the Megalopolis and Florina areas were used to capture CO2 and SO2. The regeneration ability and decay of the limestone samples were investigated through sorption-calcination cycles in a thermogravimetric analyser operated at ambient pressure. The effects of the sorption time (3, 8 and 30 min), reaction temperature (750C and 850C) and particle size (3853, 150250 and 500800 m) on the sorbent performance were examined. The two limestones demonstrated similar CO2 capture capability. Florina limestone decayed less after a specific number of cycles. When the particle size of the samples increased and the carbonation temperature was reduced, less CO2 capture was observed for both samples. The presence of SO2 inhibited the sorption ability of both limestones. Florina limestone was found to exhibit a higher sorption ability and lower decay when CO2 and SO2 were present simultaneously.

Keywords: sorption, limestone, thermogravimetric analysis, carbonation, sulphation, regeneration, global warming