Adsorption behaviours of anionic azo dye (Congo red) from aqueous solution on magnetic expanded graphite material (Eg@CoFe2O4) composites

Abstract

In this paper, a potentiality of magnetic expanded graphite material (EG@CoFe2O4) for the adsorptive removal of Congo red, an anionic azo dye, from aqueous solution was studied. The experiments were carried out in batch mode in which various experimental conditions including contact time, initial dye concentration, adsorbent dosage and pH were varied and their influences on the adsorption yield were investigated. The surface of the adsorbent before and after the removal of the dye was characterized by using FT-IR analysis. Maximum adsorption of dye was achieved at pH 6. The adsorption capacity of Congo red onto EG@CoFe2O4 was found to be as high as 101.2 (mg/g), which is higher than the adsorption capacity of the CoFe2O4 (45.7 (mg/g)). These results suggested the use of expanded graphite materials as an efficient adsorbent for decontamination of Congo red dye from factory effluents.