Sorption of zinc ions from aqueous solutions on regenerated activated carbons

This paper discusses the increasing use of activated carbons to remove wastewater contaminants and their contribution to producing wastes abundant in heavy metals. Considering their threat to the environment and their possible recovery, research on the regeneration of spent carbon sorbents and catalysts is advisable. It has also been shown that it is possible to recover activated carbon from spent catalyst (CCspent) generated by vinyl acetate synthesis by using supercritical extraction with carbon dioxide or by leaching with hydrochloric acid or a solution of nitric acid assisted by microwave energy. Activated carbon recovered in this work had a high sorption for zinc ions that was comparable to that of fresh commercial activated carbon. (C) 2003 Elsevier B.V. All rights reserved.