Extremely Efficient Adsorption of Rhodamine B dye from Aqueous Solutions onto Modified Olive Stone Activated Carbon: Modelling and Optimization Studies
Diğer yayınlar > Diğer · 2023
Yazarlar: Mert Can, Duygu OVA ÖZCAN, Bikem OVEZ
Diğer, Uluslararası, 2023,
Özet
Abstract In this study, the adsorption performances of ZnCl2, KOH and H3PO4 impregnated activated carbons derived from olive stones in the removal of Rhodamine B dye from aqueous solution were investigated. The equilibrium time was determined to be 6 hours, and the highest adsorption capacity was achieved by ZnCl2 impregnation (190.67 mg g-1) followed by KOH (118.26 mg g-1), H3PO4 (49.81 mg g-1), and crude olive stones (21.57 mg g-1) compared to the commercial powdered activated carbon (254.30 mg g-1). While different pH values (2-10) did not exhibit much effect, pH 4 was the most efficient one. The sorption capacity reached equilibrium at 200 mg L-1 of initial dye concentration. 0.01 gram of ZOSAC had 39% removal performance, whereas 0.05 gram was found to be sufficient for 100% removal. The presence of background ions enhanced the adsorption of Rhodamine B. Pseudo-second order model (R2=0.99) was most suitable for the experimental data among kinetic models. Redlich-Peterson (R2>0.98) model was found to be most suitable equilibrium model for all ACs. The temperature increase from 30 to 50℃ had an increasing effect on the adsorption capacity. It was also revealed that the adsorption was endothermic (∆H°=14.91 kJ mol-1) and thermodynamically favorable (∆G°<0) for ZOSAC. At the end of the fifth adsorption/desorption cycle, the removal efficiency was 94% and optimum adsorption conditions were determined as 45 ℃ and 252 mg L-1. As a result, ZOSAC was found to be the most efficient and reusable impregnated olive stone derived activated carbon in the Rhodamine B removal.