Influence of metal impregnants on adsorption of dimethylsulfide vapors by activated carbons

In this paper, effect of metal impregnation was studied on the textural and sorptive properties of activated carbon cloth towards adsorption of dimethyl sulfide (DMS) vapors. The activated carbon was impregnated by three different transition metal ions (Ag+, Cr6+, Cu2+). Isotherms of dimethyl sulfide were measured gravimetrically at different temperatures. The results show that the adsorption capacity of activated carbon for DMS decreased after impregnation with metals. The variation in adsorbed amount of DMS vapors on the activated carbon impregnated with different metals was discussed on the basis of the hard-soft acid base (HSAB) principle. Kinetics of adsorption has been studied by using the Linear driving force model (LDF) and Empirical diffusion model. The kinetic parameters such as rate constant (k), diffusional exponent (n), adsorbate-adsorbent interaction constant (K) and activation energy (Ea) have also been determined. The trends in isosteric heats of adsorption indicated the effect of surface heterogeneity and lateral interactions. On the basis of equilibrium, kinetics and thermodynamic studies, the suitable mechanisms for the adsorption processes occurring on impregnated carbons have been suggested. (C) 2017 Elsevier Ltd. All rights reserved.