Efficient and Eco-Friendly Sawdust Adsorbent for Methylene Blue Removal: Adsorption Optimization, Kinetics, and Isotherm Modelling

The textile industry is a major water-intensive sector that discharges dye-laden wastewater into aquatic ecosystems, posing significant environmental and public health risks. The toxic and pathogenic nature of textile dyes, including methylene blue, underscores the urgent need for innovative and sustainable water treatment methods. Therefore, in this study, we explored sawdust, which is an abundant and cost-effective waste material, as a potential adsorbent for methylene blue removal. Unlike many advanced materials that require complex synthesis, our approach highlights the practicality of using unmodified sawdust for effective dye removal. The sawdust particles were characterized by SEM, FTIR, BET, XRD, and EDX analyses. The results elucidated 96.86% removal of methylene blue at 80 mg/L dye concentration, neutral pH, 0.5 g sawdust, and 30 min contact time. Regarding the isotherm and kinetics modeling, methylene blue adsorption was simultaneous chemisorption and physisorption on the sawdust surface. This study confirms the viability of sawdust as a low-cost and accessible solution for the treatment of dye-contaminated wastewater in the textile industry. The findings could pave the way for more sustainable waste management practices, reducing both water pollution and the environmental impact of sawdust disposal.