2016 Volume 49 Issue 1 Pages 52-59
Modification of a coconut shell-based activated carbon under N2 atmosphere has been carried out using a microwave device operating at 2,450 MHz and different microwave powers. The samples were characterized by means of low temperature N2 adsorption, elemental analysis, and Boehm titration. The results show that microwave heating treatment results in a minor increase in micropore surface area and pore volume and has little effect on average micropore width. The results also show that microwave heating treatment is a very effective method for modifying the surface chemistry of the activated carbon. A gradual decrease in the surface acidic functional groups is observed, while the surface basicity is enhanced with increasing microwave power. Adsorption studies show enhanced adsorption of SO2 onto microwave-treated carbon, caused by modification of the surface chemistry. During microwave treatment, the active sites are induced by decomposition of CO-type surface oxygen groups, which favors the adsorption and oxidation of SO2.