Simultaneous adsorption of phenol and chromium(VI) from binary mixtures onto powdered activated carbon

The ability of powdered activated carbon to adsorb phenol and chromium(VI) ions, both singly and in combination, was investigated in a batch system. T he effects of initial pH and single- and dual-component concentrations on t he equilibrium uptakes were investigated. The optimum initial adsorption pH for both chromium(VI) ions and phenol was determined as 1.0. Multi-compone nt adsorption studies were performed at this initial pH value. It was obser ved that the equilibrium uptakes of phenol and chromium(VI) ions were chang ed due to the presence of other component. Adsorption isotherms were develo ped for both single- and dual-component systems at pH 1.0, and expressed by the mono- and multi-component Langmuir, Freundlich and Redlich-Peterson ad sorption models and model parameters were estimated by the non-linear regre ssion method in the studied concentration ranges. The non-competitive Freun dlich model were well fitted to the mono-component adsorption equilibrium d ata for both phenol and chromium(VI) ions while the competitive, modified F reundlich model showed good prediction in the competitive adsorption of phe nol and chromium(VI) ions on the adsorbent. The results suggested that powd ered activated carbon may find promising applications for simultaneous remo val and separation of phenol and chromium(VI) ions from aqueous effluents.