Graphene oxide/(Carboxymethylcellulose-Sodium alginate-Acrylic acid) Surface: Synthesis and Characterization for Adsorptive Removal of Azure A from Aqueous Solutions

Abstract

Graphene oxide/(Carboxymethylcellulose-Sodium alginate-Acrylic acid) was studied as the adsorbent of Azure A dye. The time to reach the equilibrium state for Azure A adsorption on the surface of hydrogel composite GO/(CMC-SA-AAC) is 120 minutes. The rate of dye adsorption on the surface of the hydrogel composite was excellent because hydrogel composite has a large surface area to absorb the largest possible amount of dye. A pseudo-first-order and a pseudo-second-order model observed Azure A dye’s adsorption kinetics on the hydrogel composite GO/(CMC-SA-AAC) surface. Illustration using the adsorption process data reflects a pseudo-second-order model. Linear forms of adsorption isotherms, Langmuir equations, Freundlich, and Timken equations were also studied. Thermodynamic effects, pH, and ionic strength effects were examined to determine the maximum absorption. Thermodynamic functions of, Enthalpy (H). Gibbs free energy (G), and Entropy (S) also were studied.