Production of activated carbons from almond shell

Abstract

The production of activated carbons from almond shell, using physical activation by CO2 is reported in this work. The used method has produced activated carbons with apparent BET surface areas and micropore volume as high as 1138m2 g−1 and 0.49 cm3 g−1, respectively. The activated carbons produced have essentially primary micropores and only a small volume of wider micropores. By FTIR analysis it was possible to identify, in the surface of the activated carbons, several functional groups, namely hydroxyls (free and phenol), ethers, esters, lactones, pyrones and Si–H bonds. By the analysis of the XRD patterns it was possible to calculate the microcrystallites dimensions with height between 1.178 and 1.881 nm and width between 3.106 and 5.917 nm. From the XRD it was also possible to identify the presence of traces of inorganic heteroatoms such as Si, Pb, K, Fe and P. All activated carbons showed basic characteristics with point of zero charge between 9.42 and 10.43.