Modeling and Optimization of Cationic Dye Removal from Aqueous Solution Using Low-Cost Adsorbent

Methylene blue as a cationic dye is ubiquitously found in aquatic systems and its presence in water resources can be hazardous. Therefore, this study aimed to investigate extensively the efficiency of activated carbon prepared from grapevine for removing Methylene Blue from aqueous solutions because of its outstanding properties such as cost-effectiveness, simple synthesis, availability, and applicational.  For this purpose, the effect of the main operational parameters such as Methylene Blue initial concentration (500-100 mg/l), adsorbent dosage (0.25-12.25 g/l), pH (3-11), and contact time (10-90 min) was optimized through surface response method. The obtained results showed that more than 97.8% of MB has been removed. The experimental data were fitted to the Freundlich model (R2=0.99) and the maximum adsorption capacity was 2.23 mg/g. Also, the adsorption kinetics are well explained by the pseudo-second-order (R2=0.91). This study shows grape waste can be used as a potential alternative candidate for adsorption of Methylene Blue from aquatic environments.