Evaluating the Adsorption of Reactive Red Dye Using Natural Zeolite: The Role of Solution Aging

Abstract

Reactive dye pollution is a major environmental problem in the textile industry. The study investigated the impacts of dye aging on the adsorption of reactive red dye using the natural zeolite. The natural zeolite was characterized by various methods, including X-ray fluorescence (XRF) and Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and Raman spectroscopic analysis. The pH and absorbance of the dye solutions were affected by the aging of the dye solutions, which led to a decrease in removal efficiency and adsorption capacity as aging progressed. The results showed that fresh dye solutions were adsorbed more efficiently than aged dye solutions, and the Freundlich isotherm showed the best fit to the experimental data. It indicates that the adsorption took place on the heterogeneous surface of the zeolite. The results suggest that the history of the dye solutions should be taken into account in adsorption studies for better remediation strategies.