Bagasse activated carbon reactivation promotes adsorption of CO2

Abstract

Activated carbon (AC) was prepared from bagasse using ZnCl2 as the activator. The new type of activated carbon (KAC) was prepared from AC using KOH as the second activator. CO2 adsorption/desorption properties were determined by thermal gravimetric analysis method (TGA). The activated carbon materials were characterized by Fourier transform infrared spectroscope (FTIR), N2 adsorption-desorption and scanning electron microscope (SEM). The results showed that CO2 adsorption quantities of KAC and AC were 3.45 mmol/g and 1.79 mmol/g, respectively at 60℃. KAC has a better adsorption capacity than AC. The CO2 adsorption capacity after five adsorption/desorption cycles showed no obvious changes, display the materials good regeneration performance. The results of FTIR spectra showed that the characteristic peaks of the two activated carbon materials were almost the same. The polarity of the activated carbon surface increased with the increase of hydroxyl and carboxyl groups on activated carbons. N2 adsorption-desorption spectra and SEM images demonstrated that all the two kinds of materials had abundant pores, and KAC had much more pores which resulted in better adsorption capacity.