Enhanced removal of cationic dyes using copper-based MOF-graphene oxide composite: Synthesis, characterization and performance evaluation

Abstract

HKUST-1, graphene oxide (GO), and their composite (HKUST-1/GO) were synthesized and characterized via FTIR, XRD, SEM, BET, and TGA. The composite was evaluated for the adsorption of Astrazon Pink FG, Cationic Red 3R, and Basic Yellow 28 dyes. Batch adsorption experiments were conducted to optimize key parameters, with maximum removal observed under the following conditions: AP FG (pH 9, contact time 80 min, 30 °C), CR 3R (pH 11, contact time 80 min, 30 °C), and BY 28 (pH 10, contact time 20 min, 30 °C). The HKUST-1/GO composite exhibited high removal efficiencies of 82.35 % (AP FG), 78.73 % (CR 3R), and 75.89 % (BY 28), with corresponding maximum adsorption capacities of 7.445 mg/g, 6.42 mg/g, and 5.58 mg/g, respectively. The adsorption followed a pseudo-second-order model and well described by Freundlich, Langmuir, Halsey, and Temkin isotherms models. Thermodynamic parameters confirmed spontaneous, exothermic dyes adsorption onto HKUST-1/GO, effectively treating industrial effluent.