Synergistic Effect of Bentonite-TiO₂-GO Hybrid Composite for High-Performance Adsorption and Photodegradation of Methylene Blue

This study focuses on synthesizing and characterizing Bentonite-TiO₂-GO composite as an advanced material for removing methylene blue dye from aqueous solution. Methylene blue, a commonly used dye in the textile industry, contributes significantly to water pollution when discharged as wastewater, posing serious threats to human health and aquatic ecosystems. To mitigate this problem, adsorption and photocatalytic degradation methods are used as effective strategies for dye removal. This study modified bentonite with TiO₂ and graphene oxide (GO) to increase its surface area, introduce active sites and enhance its photocatalytic adsorption efficiency. The synthesized (Bentonite-TiO₂)-GO composite was characterized using X-ray diffraction (XRD) and Scanning electron microscopy (SEM), which confirmed the successful formation of the composite. The optimal conditions for removing methylene blue were achieved at an initial dye concentration of 1 mg/L, with a contact time of 30 min and an adsorbent dosage of 25 mg. The highest adsorption efficiency was recorded at 87.98% in dark conditions and 89.70% under UV irradiation. Furthermore, the adsorption isotherm analysis showed that the composite followed the Langmuir and Freundlich models, indicating a combination of monolayer and multilayer adsorption mechanisms. These findings highlight the potential of Bentonite-TiO₂-GO composite as an efficient and sustainable solution for dye wastewater treatment.