Effective Adsorption of Methyl Orange from Aqueous Solution Using MOFs Nanocomposites UiO-66-NH₂/GO@PVA

The persistent contamination of water resources by synthetic dyes poses a critical global environmental challenge, necessitating the development of efficient and sustainable remediation technologies. This study presents a novel UiO-66-NH₂/GO/PVA composite for the effective removal of methyl orange (MO) from water solutions. The composite was created by combining graphene oxide (GO) and UiO-66-NH₂ in a poly-(vinyl alcohol) (PVA) matrix, creating a stable and very porous structure. Adsorption studies, fitted to the Langmuir isotherm model (<i>R</i> ² = 0.9439), revealed a maximum capacity of 188.63 mg/g, with an optimal removal efficiency of 99.6% achieved at an initial MO concentration of 100 mg/L and pH 5. Kinetic analysis confirmed a pseudo-second-order mechanism (<i>R</i> ² = 0.9930), indicating chemisorption as the dominant process, while thermodynamic data confirmed the adsorption as both endothermic and spontaneous. The material demonstrated robust reusability, retaining over 95% efficiency after four regeneration cycles. These findings position UiO-66-NH₂/GO@PVA as a promising, eco-friendly adsorbent for wastewater treatment, with future research planned to evaluate its performance in real or simulated wastewater systems, addressing practical applicability.