9. Conversion of Residual Biomass to 2D Materials for Energy and Environmental Applications

Water pollution is a critical global issue exacerbated by the release of domestic and industrial wastewater into the environment. This wastewater often contains harmful contaminants like heavy metals (e.g., Pb, As, Hg, Zn, Ni) and synthetic organic dyes (e.g., methylene blue, congo red, crystal violet), posing threats to human health and ecosystems. Adsorption using carbonaceous adsorbents offers a cost-effective, efficient, and environmentally sound solution to remove these pollutants, making it ideal for developing countries. Biomass-derived, graphene-like materials show promise as eco-friendly adsorbents with superior contaminant removal capabilities. Salix, a rapidly growing willow tree common in Canada, provides a potential source for graphene-like carbon materials through pyrolysis. This study explores a two-stage thermal pyrolysis process of Salix with NaCl addition to synthesize graphene-like materials tailored for wastewater treatment. Extensive characterization methods analyze the surface area, morphology, and crystallinity of the resulting carbon materials. The adsorption efficiency is tested by varying parameters like adsorbent dosage (0.25–1.25 g/L), contact time (0–180 min), and initial MB dye concentration (80–180 ppm). Results indicate pseudo-first-order adsorption kinetics. The synthesized carbon materials demonstrate an impressive maximum adsorption capacity of 195.4 mg/g at room temperature.