Revista de Ciencias Químicas

Investigation of Mixture Effects on the Adsorption Rates of Aromatics from Aqueous Solution on Clay and Sandy Soil

Abstract

Ebuwa I Osagie and Owabor CN

The adsorption behavior of a mixture of two polycyclic aromatic hydrocarbons (PAHs); naphthalene and pyrene and one cyclic aromatic hydrocarbon using clay and sandy soil as adsorbents was examined under ambient conditions in this study. The adsorption from the aqueous solution was observed to be time dependent and the time taken to attain adsorption equilibrium for benzene, naphthalene and pyrene in the mixture were 22, 16 h, 18 and 14 h, and 26 and 18 h in clay and sandy soil, respectively. Among the tested kinetics model in this study, the pseudo-second order equation successfully predicted the adsorption. The rate of adsorption using the pseudo-second order rate expression for benzene, naphthalene and pyrene were 0.00096, 0.00072, 0.00092 min-1 and 0.00091, 0.00080, 0.00090 min-1 for clay and sandy soils respectively. These results suggest that benzene was more selectively adsorbed than naphthalene and pyrene in both clay and sandy soil.