Removal of Eriochrome black-T by adsorption on to eucalyptus bark using green technology

Abstract

The efficiency of eucalyptus bark as a low cost adsorbent for removing an azo dye from an aqueous solution has been investigated in batch mode. The azo dye, Eriochrome black-T (EBT) is removed by adsorption over field waste eucalyptus bark after minimum chemical treatment. The investigations are carried out to study the effects of pH, adsorbate concentration, adsorbent dosage, contact time and temperature. The thermodynamic parameters were obtained from Langmuir and Freundlich adsorption isotherm models. The kinetic studies showed that the adsorption reaction is of first order. A fixed-bed column has been designed, and necessary parameters have been calculated by applying a mass transfer kinetic approach. Experiments are also performed for the recovery of loaded dye through chemical regeneration of spent columns.