INVESTIGATION INTO THE ADSORPTION PROCESS OF REACTIVE DYES BY LIGHT ASHES AND COMMERCIAL ACTIVATED CARBON AND THE OPTIMIZATION OF OPERATIONAL VARIABLES AND THEIR INFLUENCE

Abstract

This study investigated the optimization of operational variables in the adsorption process of reactive red and blue S-Matrix 150 dyes from contaminated effluent solutions. Coal pyrolysis ash was used, enabling the valorization of a low-value material with no prior practical application. Commercial activated carbon was employed as a benchmark due to its well-established effectiveness. A preliminary test was conducted under pre-established conditions until the system reached equilibrium, followed by the optimization of operational variables (pH, adsorbent mass, and initial adsorbate concentration). Both materials demonstrated significant dye removal performance, with commercial activated carbon showing superior results for the blue S-Matrix 150 dye, while the ash exhibited better performance for the red S-Matrix 150 dye. Both adsorbents achieved removal efficiencies close to 100%, highlighting their respective affinities. The search for optimal conditions revealed that the variables directly affect process efficiency, with phenomena such as active site saturation becoming evident. Therefore, coal pyrolysis ash emerges as a sustainable and low-cost alternative to commercial activated carbon, contributing to the development of more environmentally friendly technologies for wastewater treatment.