Adsorption and competition investigation of phenolic compounds on the solid-liquid interface of three-dimensional foam-like graphene oxide

Abstract Phenolic contaminants existed widely in ecological environment. Due to the various structure and functional groups, the interaction behavior of phenolic organic compounds with adsorbent was complex and changeable. Therefore, the exploration of adsorption and competition about phenolic compounds on solid-liquid interface in aqueous solution is of great significance. Herein, through a simple sugar-blowing route and post-oxidation modification, a free-standing, large-scale nanoporous three-dimensional graphene oxide (3D GO) was achieved. The synthesized 3D GO possessed hierarchical interconnected porous structure and abundant active sites, which showed excellent removal performance for many phenolic compounds. The maximum adsorption capacity ( q max ) was 135.6 mg/g, 191.3 mg/g, 237.7 mg/g, 398.6 mg/g, 420.9 mg/g and 585.8 mg/g for phenol, 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,4-dichlorophenol (DCP), bisphenol-A (BPA) and 2,4,6-trichlorophenol (TCP) at 25 °C respectively. The competitive adsorption between BPA and TCP on 3D GO was also explored. Batch adsorption experiments and characterization revealed that the outstanding performance benefited from various factors, including structural advantage, electrostatic interaction, π-π interaction, hydrophobic effect, hydrogen bond, the synergy of heteroatom and the new active sites of preferential adsorbed organics. The cost-effective and highly active 3D GO adsorbent showed great promising in environmental field, and supplied insight to understand the underlying behavior of phenolic compounds on the solid-liquid interface.