Two composite materials were synthesized based on sodium alginate and biochar derived from licorice processing waste functionalized with silicon dioxide nanoparticles (SiO2) and iron oxide (Fe2O3), respectively, enabling the valorization of industrial waste. The adsorptive capacities of the two materials (Alg-SiO2 and BCL-Fe2O3) toward CO2 in the gaseous stream with nitrogen were evaluated by acid titration of carbonates present in a trap for CO2 consisting of a KOH solution placed downstream of the adsorption column. The aim of the present work is to evaluate the CO2 adsorption capacity of material functionalized by nanoparticles. Adams–Bohart, Thomas models, and % removal efficiency curves for the adsorption were examined to investigate the dynamic behavior of the column. From the tests performed in CO2 and N2 flow, the BCL-Fe2O3 material was demonstrated to have an adsorbent higher capacity than Alg-SiO2, respectively CO2 adsorbed 25 and 6 mg/g.