Preparation and CO _2 sorption of a high surface area activated carbon obtained from the KOH activation of finger citron residue

摘要

A high surface area activated carbon was synthesized by potassium hydroxide (KOH) activation of Finger Citron residue. The pore structure of the as-synthesized activated carbon was characterized by nitrogen adsorption and its carbon dioxide (CO _2) sorption capacities at different conditions were measured under high pressure. The BET surface area and total pore volume of the as-synthesized sample were 2887 m _2/g and 1.23 cm _3/g, respectively. The dry sample exhibited a CO _2 adsorption capacity of 19.21 mmol/g at 276 K and 3.57 MPa. The CO _2 adsorption uptake increased considerably when an amount of water was pre-adsorbed onto the sample, possibly as a result of the formation of CO _2 hydrate in the pore spaces of the activated carbon. The maximum CO _2 adsorption capacity of the wet sample was found to be 29.02 mmol/g at 273 K and 3.57 MPa. Overall, the results reported confirm that Finger Citron residue could prove a promising precursor for high surface area activated carbon and point to the potential application of activated carbon made from Finger Citron residue in carbon capture and storage.