Comparison of the adsorption behavior of Basic Red 46 textile dye on various activated carbons obtained from Zonguldak coal

Abstract

The activated carbons obtained by physical and chemical activation techniques from Zonguldak-Kilimli region coal was used for the adsorption of a textile dye, Basic Red 46 from aqueous solutions. The effects of adsorbent preparation method, initial dye concentration and temperature on adsorption were investigated. The color removal performance of activated carbons prepared by physical activation (PAC), chemical activation with KOH (CAC) and the commercial activated carbon (AC) were compared. The batch adsorption experiments were carried out isothermally at 25, 30 and 35°C. The adsorption capacities at 25, 30 and 35°C were found as 62.7, 23.1, 19.6 (PAC); 201.6, 215.1, 231.5 (AC); and 277.8, 307.7, 323.6 mg g- 1 (CAC), respectively. It was found that the CAC sample having the highest micropore and surface area obtained by thermal treatment with KOH had the highest adsorption capacity. The results have shown that the adsorption of BR 46 exhibited an endothermic character on CAC and AC, and exothermic character on PAC. Kinetic data were adequately fitted by the pseudo- first order kinetic model. The study has shown that activated carbon obtained by KOH activation of coal could be effectively used for the adsorptive removal of BR 46 textile dye from wastewaters. The activated carbon obtained from Zonguldak coal with low cost, non toxic character and excellent adsorption performance has a high potential for sustainable commercial applications.