Carbon dioxide adsorption and decolourizing power of activated carbons prepared from Pistacia shells

A series of activated carbons 'Z' was prepared from Aleppo Pistacia Vera shells using different percentages of zinc chloride at 873 K in the absence of air. Another series 'ZN' was prepared using the same conditions as for the 'Z' series but employing a nitrogen atmosphere to effect carbonization. The textural properties of the two series of samples were determined from the adsorption of carbon dioxide and methylene blue at 298 K. Activated carbons with a high adsorptive capacity for methylene blue were obtained, Activation with zinc chloride proceeded with increasing microporosity via the creation of new micropores. At high percentages of zinc chloride, slight partial pore widening may take place. Carbon dioxide was accessible to the entire pore system and was therefore suitable as a probe for the investigation of the textural properties of the activated carbons studied, A fraction of the porosity was inaccessible to methylene blue molecules and consequently lower surface areas were calculated from the adsorption of this dye molecule.