Development of Zinc Oxide-Sawdust Composite Adsorbent for Methylene Blue Removal: Synthesis, Characterization and Adsorption Mechanism

The natural world provides sawdust, also known as wood shavings, which is a reasonably abundant and affordable lignocellulosic compound. It is a waste product of agriculture and industry that is abundant and has disposal issues. A zinc oxide nanocomposite based on sawdust (ZnO@SD) was synthesized to efficiently remove the dye methylene blue (MB) from aqueous solutions. FTIR, SEM, TEM, and XRD analyses were used to characterize the freshly made sawdust material. Batch optimization of adsorption experimental parameters, including initial dye concentration, contact time, solution pH, temperature, and adsorbent dosage used, to achieve the maximum removal of MB dye from wastewater. For an initial MB dye concentration of 50 mg/L, the ideal parameters for the maximum removal of MB dye from aqueous solution were determined to be: 40 mg of adsorbent, 80 minutes of contact time, a pH of 6.0, and 25°C. The models that best fit the examined experimental data were the Freundlich and pseudo-second order. For the removal of MB dye, the experimental adsorption capacity of ZnO@SD was found to be 372.5 mg/g. According to the obtained results, the sawdust composite was thought to be a low-cost and efficient adsorbent for dye removal.