Optimization performance of viscose rayon derived flexible porous carbon cloths in relation to their CO2 capture, CO2/CH4 separation and methanol adsorption

From the practical perspective, innovative porous carbon material is needed for gas adsorption and separation. Here, flexible porous carbon cloths are successfully prepared from viscose rayon cloth via controllable adjusted KOH activation. In order to optimize such flexible porous carbon cloths, the relationship between KOH activation condition and the porous carbon cloths property have been systematically studied. The effect factors on CO2 capture, CO2/CH4 separation and methanol adsorption have been analyzed in depth. Due to the largest narrow micropore volume (PV1 nm), ACC-240-800 exhibits the best CO2 uptake capacity of 4.11 mmol g-1 under ambient condition. Based on the ideal adsorbed solution theory model, the ACC-240-700 exhibits the highest selectivity of 3.73, 3.13 and 2.65 for CO2/CH4 mixing proportion of 30/70, 46/60 and 50/50, respectively, at 25 degrees C and 1 bar, owing to the synergetic result of O&N content and PV1nm. The CO2/CH4 separation performance on ACC-240-700 is analyzed and confirmed by Qst calculation for CO2 and CH4, and dynamic breakthrough experiments with equimolar binary CO2/CH4 (50/50) mixture. The determining factors on methanol adsorption is mainly the porosity structure. The best methanol adsorption uptake of 12.87 mmol g-1 is observed on ACC 240-800 at 25 degrees C and 95 mbar, because of the largest values of SBET, Vmicro and PV1mn. The flexible porous carbon cloths provided in this work can act as effective adsorbent for carbon capture, low-quality nature gas upgrading and methanol adsorption in the industrial processes.