Canadian Journal of Chemical Engineering, Vol.97, No.11, 2961-2968, 2019
CO2 CAPTURE EFFICIENCY IN POST-COMBUSTION USING MWNT-PAA IN A PACKED BED COLUMN
The adsorption capacity of polyaspartamide (PAA) and multi-wall carbon nanotubes with polyaspartamide (MWNT-PAA) was investigated through a packed bed column with the flowing of flue gas composed of 15 % CO2, 5 % O-2 and the balance N-2. The adsorption performed at 25 degrees C, 110 kPa and inlet gas flow rate of 60 mL/min resulted in high CO2 adsorption capacity of 5.70 and 10.20 mmol-CO2/g for PAA and MWNT-PAA, respectively. The adsorption kinetics was very high, so 7 min were enough for the effluent gas to reach the breakthrough after saturation. The consistency of adsorbents in recurring regeneration was successful through a continuous TSA system of 10 cycle adsorption-desorption with temperatures of 25-100 degrees C. The evaluation of heat through differential scanning calorimetry (DSC) resulted in exothermic adsorption with heat release of 45.14 kJ/mol and 124.38 kJ/mol for PAA and MWNT-PAA, respectively. The heat release was found favourable to promote the desorption as the temperature could rise after adsorption. This is an advantage for energy efficiency, as it depicts the potential of energy recovery. Thus, both adsorbent PAA and MWNT-PAA were demonstrated to be promising for CO2 adsorption capture in post-combustion.