This study explores the effectiveness of highly porous graphene-based carbons derived from biomass as an adsorbent for removing phenol from aqueous solutions. The graphene-based carbons were extensively characterized using electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and BET analysis. They predominantly consisted of sp2-bonded carbons and demonstrated an exceptionally high specific surface area with an interconnected pore structure. This unique structure enables effective phenol adsorption primarily through favorable π-π interactions, resulting in outstanding adsorption capacity. Both Langmuir and Freundlich isotherm models provided excellent fits to the adsorption data, confirming the favorable phenol adsorption characteristics of the carbons. Furthermore, the adsorption kinetics were well-described by non-linear pseudo-first-order (PFO), pseudo-second-order (PSO), and linear intraparticle diffusion (IPD) models, indicating that phenol adsorption occurs through a physisorption mechanism involving the phenolic ring and the basal plane of the carbon. This study underscores the potential of biomass-derived graphene-based carbon as a cost-effective and efficient adsorbent for phenol removal, offering promising implications for sustainable water treatment solutions.