Hybrid adsorbents based on cellulosic waste–derived activated carbon and mill scale: Structural insights and application in removing diverse contaminants

In this study, raw mill scale was integrated with paper waste–driven activated carbon (AC@MS) to develop novel hybrid adsorbents for wastewater treatment. The hybrid adsorbents were fabricated via a ball-milling process and characterized by XPS, EDS, XRD, SEM, BET, FTIR, and TGA analyses. The results showed that activated carbon effectively filled mill scale pores, creating a more homogeneous surface and increasing surface area. The AC@MS2 sample exhibited high removal efficiencies for rhodamine B dye (97.7%) and Cu2+ ions (97.0%), following multilayer and monolayer adsorption mechanisms, respectively. The adsorption processes were spontaneous, with RhB removal being endothermic and Cu2+ removal exothermic. The material also showed strong activity toward other cationic and anionic dyes. These findings highlight the potential of AC@MS hybrids as low-cost, eco-friendly adsorbents. Importantly, their sustainable production from industrial and paper waste suggests promising real-world applications in large-scale wastewater treatment and industrial effluent management.