Facil for synthesis super adsorbent from surface-charged bay leaves for elimination of malachite green dye from aquatic environment
Eman Ibrahim Ahmed, Doha Neithal Saad
Abstract
In this study a super adsorbent material using surface-charged bay leaf powder with SDS surfactant was synthesized by ultrasonication to remove malachite green dye from aquatic environments. The adsorbent (S-CBL) was characterized using FESEM-EDX, FT-IR, XRD, and pH zero-point charge (pHpzc). The S-CBL adsorbent demonstrated the highest maximum adsorption capacity (qmax = 633 mg/g) with a removal efficiency of 98.8% under optimal conditions: an initial dye concentration of 300 ppm, adsorbent dosage of 0.7 g/50 mL, pH of 6, temperature of 15 °C, and contact time of 20 min. The linear adsorption isotherm data fit the Freundlich model, while the nonlinear isotherm adsorption followed the Langmuir model. Kinetic studies revealed that the MG dye adsorption process adhered to the pseudo-second-order kinetic model (R² > 0.99) for both linear and nonlinear kinetics, indicating a physicochemical adsorption mechanism. Thermodynamic studies confirmed that the adsorption process was feasible, spontaneous, and exothermic. A possible adsorption mechanism, based on electrostatic interactions and hydrogen bonding between the anionic surface of the adsorbent and the cationic dye molecules, was proposed. The results demonstrate that surface-charged bay leaves are highly effective, inexpensive, and one-step strategy, making them a promising adsorbent for removing harmful organic dyes from aquatic environments can be suitable adsorbent for removing toxic dyes on the industrial scale.