Structure of impregnated active carbons produced with almond shells - influence of impregnation methodology

Activated carbons impregnated with CoO, Co3O4 and CrO3 were prepared, to be used in the oxidative destruction of atmospheric organic pollutants. To an alyse the influence of impregnation methodology on the structure, the impre gnation step was conducted after activation and after carbonization. When i mpregnation is made after activation, the impregnated salts must be deposit ed on the internal surface, blocking the access to part of the initial stru cture. When impregnation is made after carbonization, the impregnated activ e carbons have even more important contribution of micro and mesoporosity. The metallic impregnants catalyse the activation step, allowing a controlle d development of the larger micropores and mesopores, i.e. bigger for highe r metal percentages and with Co3O4 as catalyst. (C) 2000 Elsevier Science L td. All rights reserved.