In this study a high flux circulating-turbulent fluidized bed (CTFB) riser was confirmed to be advantageous for carbon dioxide (CO2) sorption on a potassium carbonate solid sorbent. The effect of various parametdrs on the CO2 removal level was evaluated using a statistical experimental design. The most appropriate fluidization regime was found to occur between the turbulent and fast fluidization regimes, which was shown to capture CO2 more efficiently than conventional fluidization regimes. The highest CO2 sorption level was 93.4% under optimized CTFB operating conditions. The important parameters for CO2 capture Were the inlet gas velocity and the interactions between the CO2 concentration and the inlet gas velocity and water vapor concentration. The CTFB regime had a high and uniform solid particle distribution in both the axial and radial system directions and could transport the solid sorbent to the regeneration reactor. In addition, the process system continuity had a stronger effect on the CO2 removal level in the system than the process system mixing. (C) 2016 Elsevier Ltd. All rights reserved.