Metals Incorporated Agricultural Waste Corn Cob-based Biochar Used as An Adsorbent for CO2 Capturing

Abstract This research aims to use the agricultural waste corn cob-based biochar CO 2 adsorption capacity by incorporating Magnesium and Sodium metals into its structure. The corn cob was pyrolyzed at a temperature of 900°C to create biochar for this purpose. The biochar had a higher microporosity fraction and a large specific surface area when impregnated with metal with heat treatment under N 2 . The biochar was characterized by pore volume (25%), specific surface area (346.2 m 2 /g), average particle size (0.52 nm), and point zero charge (pH = 5.12). According to XRD examination, Mg boosted the degree of carbon structure ordering, whereas Na improved crystal structure formation. SEM analysis revealed that the biochar surface impregnated with metal oxide had a distribution of spotted activation centers. The combined effects of physical and chemical interactions may account for the Mg-loaded biochar's higher CO 2 adsorption at 25°C and 1 atm. The adsorption of CO 2 onto biochar was in the order of Mg metal-incorporated biochar > Na metal-incorporated biochar > pristine biochar. The SEM images also reflected the results. The EDX data from the elemental analysis also agreed with the higher CO 2 uptake capacity of Mg-loaded biochar. The XPS spectrum and 13 C NMR also agreed with the EDX results. The efficiency of adsorption of CO 2 in Mg-loaded biochar was 94.6%, which was higher than Na-loaded biochar (81.20%) as well as pristine biochar (64.43%). Thus, we can say that corn cob-based biochar is a low-cost option for CO 2 capture systems in natural environments, offering a higher efficiency rate.