Copper removal from wastewater via clinoptilolite: The diffusion kinetic analysis

Abstract

This study investigates the kinetic models of Cu²⁺ ion adsorption onto clinoptilolite-rich zeolite. The study highlights the importance of diffusion kinetic models in understanding the adsorption process. The initial phases are significantly influenced by the ion diffusion through the film to the particle surface, particularly within the first 30 minutes, which is crucial for the heterogeneous surfaces like zeolites. Following this, the surface adsorption (intraparticle diffusion) is described by the Weber-Morris model, effective primarily during the initial stage. As the process progresses beyond 20-30 minutes, the ion removal rates decrease sharply, and diffusion within the particle core becomes the dominant factor, influencing the overall reaction rate.