Sustainable bio-based sorbents for emerging and multi-contaminant removal from wastewater

The widespread presence of organic pollutants in urban wastewater effluents underscores the need to implement advanced quaternary treatment steps, thereby driving the development of sustainable and scalable remediation technologies. This study explores the synthesis and application of bio-based materials derived from renewable vegetable oils via a facile, scalable polymerisation strategy, yielding hydrophobic, thermally resistant materials. The sorption performance was evaluated in batch experiments using representative contaminants, including oils, dyes, and antibiotics, demonstrating high uptake capacities and rapid adsorption kinetics across different pollutant classes. The best-performing sorbent material exhibited an oil uptake capacity of 2.38 g g−1, a dye removal efficiency of 85%, and an antibiotic removal efficiency of 59%, consistent with pseudo-second-order models. To bridge laboratory studies and practical applications, a composite zeolite-biomaterial mixture (SOGS_Zeo) was validated under dynamic flow conditions using a small-scale (100 mL) continuous system for the removal of doxycycline and rhodamine B, followed by scale-up testing in a pilot plant treating 100 L of antibiotics-contaminated treated wastewater at different concentrations. The composite significantly increased the removal efficiency to 100% under continuous-flow conditions and exhibited good recyclability, confirming its structural robustness and applicability in realistic treatment scenarios. These results highlight the potential of vegetable oil-derived materials as sustainable and scalable adsorbents for inclusion in wastewater treatment plants as quaternary treatment systems.