Bio-Graphene Foam: A Robust Solution for Adsorptive and Sustainable Chlorophenol Removal from Wastewater

Abstract

This study focuses on the innovative production of Bio-Graphene Foams (BGFs) from sustainable resources, aimed at addressing the critical challenge of efficiently removing harmful chlorophenols—specifically 2,4-dichlorophenol (DCP) and 2,4,6-trichlorophenol (TCP)—from wastewater. In this investigation, we present an innovative and streamlined methodology to address the constraints encountered in the fabrication of biomass-derived Graphene Foams (bGFs). Our primary focus is on customizing their extensive surface area and structural attributes to align with the specific requirements of environmental applications, particularly for the adsorption of chlorophenols. We developed a distinctive BGF with a highly porous, spongy structure and an impressive specific surface area of up to 805 m²/g through a two-step synthetic process. Our method not only enhances the environmental applicability of BGFs but also demonstrates their superior adsorptive capabilities. The adsorption performance of the BGFs was rigorously evaluated, with a focus on capacity, kinetics, and the influence of pH. Comprehensive studies on the effects of pH, contact time, adsorbent dosage, and phenolic content were conducted. The adsorption isotherms for DCP and TCP adhered to the Langmuir model, revealing an outstanding adsorption capacity of 245 mg of pollutant per gram of BGF at an optimal pH of 3–4. Remarkably, BGFs reduced the concentration of phenolic derivatives in water to levels below the World Health Organization’s acceptable limit for human use (0.050 mg/dm³). This research highlights the significant potential of Bio-Graphene Foams as highly effective adsorbents for environmental remediation. The challenges associated with synthesizing such high-performance materials and optimizing their application for wastewater treatment were successfully addressed, marking a substantial advancement in the field.