<p>Phenolic compounds persist in aquatic environments and are toxic, necessitating efficient treatment strategies. This study evaluated phenol adsorption onto three materials—calcined magnesium–aluminum layered double hydroxide, partially reduced graphene oxide, and a calcined magnesium–aluminum layered double hydroxide–graphene composite—using a synthesis route designed to increase surface area and porosity. The methodology combined batch adsorption experiments with response surface methodology to optimize operational conditions, and applied kinetic, isotherm, diffusion, and thermodynamic analyses to elucidate mechanisms. The optimal conditions were 60 mg per liter initial phenol concentration, 50 degrees Celsius, 3 g per liter adsorbent dosage, and 110 min, yielding 93.67 percent removal with the layered double hydroxide–graphene composite. Findings showed adsorbent dosage was the most influential variable. Kinetic analysis followed a pseudo-second-order model, indicating chemisorption. The Freundlich isotherm best captured equilibrium behavior, consistent with multilayer adsorption on a heterogeneous surface, while Temkin and Dubinin-Radushkevich interpretations suggested decreasing adsorption energy and a mixed physical–chemical mechanism. Weber-Morris evaluation indicated contributions from both film diffusion and intra-particle diffusion. Thermodynamics confirmed spontaneous and endothermic adsorption with increased entropy at the solid–liquid interface. In discussion, the composite’s heterogeneous sites and transport characteristics explain its superior capacity and robustness. In conclusion, the composite maintained about 90 percent removal after five regeneration cycles, demonstrating practical promise for wastewater treatment under environmentally relevant conditions.</p>