Effects on Surface Area, Intake Capacity and Regeneration of Impregnated Palm-Shell Activated Carbon with Monoethanolamide and 2-Amino-2-Methyl- 1-Propanol Equipped For CO2 Adsorption

Abstract

Granular palm shell activated carbon (AC) was impregnated separately with monoethanolamine (MEA) and 2-amino- 2-methyl-1-propanol (AMP) to improve its natural capacity and selectivity for carbon dioxide (CO2) adsorption. The total surface area, micropore volume, as well as the heterogeneity of the impregnated AC particles was considerably reduced due to impregnation. CO2 intake of impregnated 500 μm AC particles improved significantly and adsorptive capacity of 500 μm MEA-impregnated AC particles improved by 172% and 44% comparing to non-impregnated and AMP-impregnated AC particles respectively. Solid state amine stoichiometric results indicated that adsorption capacity of unhindered amine (MEA) is higher than that of hindered amine (AMP) by 50% contrary to liquid amines standard stoichiometry. Exhausted AMP-impregnated beds were regenerated by sweeping at room temperature with stream of pure nitrogen (N2) flowing at 60 ml/min for 4 hours. Heating up to 75°C was required to regenerate exhausted MEAimpregnated beds. Increasing feed gas flow rate has adverse effect on breakthrough time more than increasing bed operating temperature. Breakthrough time was utilized to evaluate the performance of the different adsorption beds.