Recent advances in remediating organic-laden wastewater using graphene-based nanomaterials

Due to their unique adsorptive potentials, graphene-based nano-composites [especially graphene oxide (GO)] have been recently researched intensively for sequestrating organic pollutants, such as dyes and pharmaceuticals. These pollutants are primarily adsorbed via π–π, H-bond, and electrostatic interactions, achieving 37–1148 mg g⁻¹ maximum adsorption capacities. This review identifies the influence of pH, temperature, sorbate concentration, and sorbent dosage on the sorbate-sorbent interface. The investigated adsorptions occurred within pH 2–12, promoting cationic surfaces that achieved up to 394.6 mg g⁻¹. Also, both dyes and pharmaceuticals were predominantly removed endothermically (≥ 532.6 mg g⁻¹) than exothermically (≥ 14.10 mg g⁻¹). Further reusability tests over 3–15 cycles accomplished between  > 50 and 100% removal efficiencies. In comparison, zeolites were other adsorbents with similar performances to functionalized GO, except that GO exhibits superior affordability, mechanical strength, specificity, and reusability. However, simultaneous removal of dyes and pharmaceuticals using GO requires further research for improved performance.