Removal of different basic dyes from wastewaters by various biomasses

The aim of this study was to remove Basic Blue 41 (BB41) and Basic Violet 16 (BV16) dyes by adsorption process. In the experiments, the effects of pH value, adsorbent dosage, test period, initial dyestuff concentration and temperature on the adsorption process were examined. Acorn cupule (Quercus coccifera) and waste sage tea (Salvia Officinalis) were used as adsorbents. The experiments were carried out with adsorbents with a particle size range of 125-500 µm. In the studies conducted with BB41 solution, while the pH value was 8 and the adsorbent dosage was 0.1 g/100 mL, it was determined that 95.8% efficiency was achieved for acorn cupule and 95.97% efficiency for waste sage tea. In studies carried out with BV16 solution, 87.25% removal efficiency was obtained for acorn cupule and 91.33% removal efficiency for waste sage tea at the same pH value and adsorbent dosage. These values obtained are valid for studies performed at 25 °C. As a result of isotherm modeling studies, when the isotherm models were compared, it was determined that the acorn cupule was compatible with the Langmuir model and the waste sage tea adsorbent was generally compatible with the Freundlich isotherm model. While acorn cupule presented maximum uptake capacities of 222.22 mg/g and 106.38 mg/g for BB41 and BV16 dyes, respectively, waste sage tea exhibited maximum uptake capacities of 344.83 mg/g and 147.06 mg/g for BB41 and BV16 dyestuffs, respectively. In the comparison of kinetic and diffusion models, it was determined that both adsorbents suited the pseudo-second-order kinetic model. When the adsorbents are compared, it is observed that waste sage tea has slightly better removal efficiency and better uptake capacity than acorn cupule even at low dosage, and it has been concluded that both adsorbents have significant adsorption potential for different basic dyes and are promising in terms of being innovative and environmentally friendly.