Fluidity comparison of biomass-derived activated carbon and TiO(OH)2 and its improving toward promoted low-temperature CO2 capture in gaseous medium

Abstract

Biowaste-derived activated carbons (ACs) and TiO(OH)2 are considered promising materials for effective CO2 capture. TiO(OH)2 has not been employed in gas phase adsorption process; moreover, the comparison of fluidization of these materials had not been investigated. Hence, this study not only did evaluate the CO2 adsorption performance of both synthetic TiO(OH)2 and biomass-derived AC, but also assessed their fluidity aimed to implement at pilot scales. The samples were examined using XRD, BET, SEM, EDX, FTIR, and TGA techniques. The adsorption of the adsorbents was evaluated through TGA under several conditions. The AC demonstrated an average CO2 capture capacity of 3.54 mmol/g, surpassing that of the TiO(OH)2 (0.971 mmol/g) during three successive cycles at 25/120 ℃ under a CO2/N2 flow of 90/10 vol% and 1 bar. Adding 5 wt% of auxiliary SiO2 nanoparticles enhanced bed expansion of AC and TiO(OH)2 by 1.83 and 1.5 times respectively, due to dwindling interparticle cohesive interactions.