(8h) Green Synthesis of Lignin-Based Magnetic Mesoporous Activated Carbon for Efficient Methylene Blue Adsorption from Wastewater

Lignin-based carbon materials (LCMs) have garnered significant attention for lignin valorization, offering diverse applications such as environmental remediation, energy storage, catalysis, drug delivery, and flexible electronics. Lignin's high carbon content and phenylpropane units make it a suitable precursor for producing functional carbon nanomaterials, leading to recent research focus. Among the LCMs, Magnetic mesoporous activated carbon (MMAC) combines the properties of mesoporous structure, high surface area, and magnetic responsiveness, making it a versatile material for applications in wastewater treatment, environmental remediation, etc. Its unique characteristics enable efficient adsorption of contaminants and facile recovery from aqueous solutions, enhancing its utility in diverse fields. However, conventional methods for preparing LCMs involve using toxic and carcinogenic phenolic compounds as carbon precursors and aldehydes as crosslinkers. This study introduces a novel method for synthesizing Magnetic Mesoporous Activated Carbon (MMAC) by electrocoagulating black liquor, followed by carbonization at various temperatures in a more sustainable approach, using lignin as the carbon precursor and iron hydroxides as crosslinkers. Characterization techniques, including BET, Raman spectroscopy, SEM-EDS, XRD, and FTIR, confirm the successful formation of MMAC following the carbonization of electrocoagulated lignin. Methylene blue, a persistent, toxic, carcinogenic, and mutagenic cationic dye, was chosen as a model pollutant to evaluate the adsorption capacity and reusability of the synthesized MMAC. This study also investigated the structural and morphological changes of MMAC during adsorption cycles.