Honeycomb monoliths of activated carbons for effluent gas purification

During the incineration of urban waste incomplete mineralisation of some organic species can give rise to effluents contaminated with VOCs, furans and dioxins. These units produce large volumes of gas to be treated, but with low contents of these toxic species, for which the pressure drop caused by passing through a conventional pellet adsorption bed can be considerable. Another solution is to spray activated carbon powder into the contaminated effluent gas, although this is an expensive method. Thus, to avoid the problems associated with pressure drop or high operation costs, commercial activated carbons have been conformed as open-channel honeycomb monoliths. Their adsorption capacities towards an aromatic probe molecule, o-dichlorobenzene, chosen to simulate dioxins have been tested in a static regime. The results were analysed together with the textural and mechanical properties of the monolith composites in order to establish criteria by which the most suitable honeycomb monolith composite material for industrial use could be prepared. (C) 2000 Elsevier Science B.V. All rights reserved.