Investigation of Cu/Zn/Ag/Mo-based impregnated activated carbon for the removal of toxic gases, synthesized in aqueous media

Abstract

Impregnated activated carbons (IACs) have been prepared successfully from aqueous solution of copper, zinc, silver and molybdenum for the removal of toxic gases from air. First, the activated carbon was impregnated by imbibing limit method with single metal, then a combination of 2 to 4 metals was used. The aim of this study was to access the adsorption capability of raw activated carbons (RAC) and IACs for SO2 and NO2 gases. Different techniques such as XRD, TEM, SEM, EDX mapping, AAS and BET surface area analyzer were used for characterization of materials. Results indicate that IACs provided satisfactory protection against challenge gases. Using the FTIR based gas analyzer, a significant increase in breakthrough time of all IACs was observed as compared to RAC. The maximum breakthrough time was achieved with four metals (Cu, Zn, Ag and Mo) impregnated on activated carbon i.e. 120.5 min for SO2 and 139.0 min for NO2, which were 13 and 25 times high respectively, in comparison with RAC. Adsorption capacity was found to be 320 mg SO2/g-C and 380 mg NO2/g-C. In comparison with RAC, ASZM2 carbon showed enhanced adsorption capability up to 30 times for SO2 and 40 times for NO2.