ADSORPTION PERFORMANCE OF TARTRAZINE BY Cu x -ZnO COMPOSITE SYNTHESIZED VIA ELECTROCHEMICAL METHOD O y

Abstract

In this study, a Cu x O y /ZnO (CZO) composite was synthesized and evaluated for the adsorption of tartrazine (TA), a common azo dye in food and industrial applications. The effects of various parameters including pH, contact time, adsorbent dosage, and initial dye concentration were systematically investigated. The adsorption efficiency reached over 96% at pH 5 with 0.015g of CZO for 50mL of 100mg/L TA solution, while the maximum specific adsorption capacity exceeded 500mg/g at higher dye concentrations. Equilibrium was achieved after 90 minutes. Experimental data were fitted to four isotherm models, among which the Freundlich model gave the best correlation (R² = 0.9802), with n = 3.68 indicating favorable multilayer adsorption on a heterogeneous surface. The Langmuir model also showed good agreement (q max = 520.83mg/g, R² = 0.9532), suggesting the presence of localized monolayer adsorption. Kinetic analysis revealed that the pseudo-second-order model provided the best fit (R² = 0.9998), indicating that chemisorption played a dominant role. These findings highlight the potential application of CZO as an effective and low-cost adsorbent for dye removal from wastewater.