Highlights:Graphical/Tabular Abstract Dye removal performances of activated carbons from Zonguldak coal Adsorption of Basic Red 46 textile dye Activated carbon obtained by thermal treatment with KOH Figure A. Adsorption behavior of Basic Red 46 dye on PAC, CAC, and AC (Co: 25 mg L -1 ; mads:10 mg; T: 25 o C)Purpose: The purpose of the research was to evaluate the activated carbons obtained by physical and chemical activation techniques from Zonguldak-Kilimli region coal for the adsorption of a textile dye, Basic Red 46 from aqueous solutions. Investigating the effects of adsorbent preparation method, initial dye concentration and temperature on adsorption and comparing the color removal performance of activated carbons prepared by physical activation (PAC), chemical activation with KOH (CAC) and the commercial activated carbon (AC) were also aimed.
Theory and Methods:The activated carbons obtained by physical and chemical activation techniques from Zonguldak-Kilimli region coal were used for the adsorption of Basic Red 46 textile dye from aqueous solutions. The effects of adsorbent preparation method, initial dye concentration and temperature on adsorption were investigated. The color removal performance of PAC, CAC and AC were compared. The batch adsorption experiments were carried out isothermally at 25, 30 and 35 C. The equilibrium adsorption data were evaluated using the Langmuir and the Freundlich isotherm models. Kinetic data were analyzed using the pseudo-first and the second order kinetic models.
Results: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 dye 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.
Conclusion:The study has shown that the activated carbon obtained by KOH treatment 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.