SO_2 adsorption capacity of K_2CO_3-impregnated activated carbon as a function of K_2CO_3 content loaded by soaking and incipient wetness

摘要

The SO_2 adsorption capacity of K_2CO_3-impregnated activated carbons, prepared by soaking carbon in large volumes of K_2CO_3 in solution of various concentrations, varies linearly with respect to the loading of K_2CO_3 on the carbon up to about 12% K_2CO_3 by weight. Above 12%, the capacity for SO_2 levels out and then decreases. This suggests that at high loadings the K_2CO_3 either aggregates and/or blocks pores of the activated carbon. In contrast, the adsorption capacity of carbons prepared by repeatedly (maximum of three times total) loading K_2CO_3 via incipient wetness is much larger than that of the soaked samples, up to 70% more, when the loading of K_2CO_3 is greater than 12%. Static and dynamic adsorption, DSC, SEM, EDX and incipient wetness studies of the samples show that the impregnant aggregates but does not block carbon pores.