The study presents the preparation and characterization of a hydrogel membrane composed of activated carbon, sodium dodecyl sulfate-modified montmorillonite clay, and sodium alginate. The activated carbon was derived from a locally available subsite plant using boric acid as an activating agent. The physicochemical properties of the hydrogel membrane were characterized using FTIR, SEM, EDX, and TGA techniques. The membrane's performance as an adsorbent for methyl red dye was evaluated under various conditions, including pH, membrane dose, equilibrium time, solution temperature, and dye concentration. The maximum adsorption capacity of the hydrogel membrane was found to be 248.13 mg g\(^{-1}\). Kinetic studies indicated that the adsorption followed the pseudo-second-order model, while equilibrium data were best described by the Freundlich isotherm. Thermodynamic analysis revealed that the adsorption process was spontaneous, favorable, and endothermic. The hydrogel membrane showed good regeneration and reusability, making it a promising material for the removal of methyl red from water solutions.The study presents the preparation and characterization of a hydrogel membrane composed of activated carbon, sodium dodecyl sulfate-modified montmorillonite clay, and sodium alginate. The activated carbon was derived from a locally available subsite plant using boric acid as an activating agent. The physicochemical properties of the hydrogel membrane were characterized using FTIR, SEM, EDX, and TGA techniques. The membrane's performance as an adsorbent for methyl red dye was evaluated under various conditions, including pH, membrane dose, equilibrium time, solution temperature, and dye concentration. The maximum adsorption capacity of the hydrogel membrane was found to be 248.13 mg g\(^{-1}\). Kinetic studies indicated that the adsorption followed the pseudo-second-order model, while equilibrium data were best described by the Freundlich isotherm. Thermodynamic analysis revealed that the adsorption process was spontaneous, favorable, and endothermic. The hydrogel membrane showed good regeneration and reusability, making it a promising material for the removal of methyl red from water solutions.