Abstract:The pure 3CaO·2SiO2(C3S2) was prepared as clinker and hardened via accelerated carbonation. The CO2 uptake, mechanical properties and microstructure changes were analyzed by XRD, thermo gravimetric analysis(TG, DTA), FTIR and SEM EDS.The results show that degree of CO2 curing of the clinker reached 433% that results in compressive strength of 748MPa after 24h carbonation in 99%(by volume) CO2concentration; the carbonation product is calcium carbonate and silica gel, which contributes to the compressive strength.