Eco-friendly preparation of carbon-silica modified calcium aluminosilicate nanoparticles using waste coal ash for collaborative adsorption and degradation of methylene blue

This paper investigates the adsorption and degradation of methylene blue using carbon-silica modified calcium aluminosilicate nanoparticles (CS_CA NPs). The carbon-silica modified calcium aluminosilicate was synthesized from waste coal ash, providing a sustainable and eco-friendly approach. The adsorption process was studied by examining the effects of various parameters such as pH, contact time, and adsorbent dosage. The results demonstrated that the carbon-silica modified calcium aluminosilicate nanoparticle exhibited excellent adsorption capacity for methylene blue, with a maximum removal efficiency of 85 %. The adsorption kinetics followed a pseudo-second-order model, indicating a chemisorption process. Furthermore, the adsorption isotherms were well-fitted to the Langmuir model, suggesting monolayer adsorption. To enhance the removal of methylene blue, catalytic experiments were conducted in the presence of H 2 O 2 . The carbon-silica modified calcium aluminosilicate nanoparticles exhibited peroxidase and catalase-like activity, which contributed to the degradation of methylene blue at broad range of pH. The calcium aluminosilicate nanoparticles acted as catalysts in the presence of H 2 O 2 , generating reactive oxygen species (ROS) that oxidized and broke down the dye molecules. The degradation efficiency reached 99 % within 30 min. The catalytic process was found to follow a pseudo-first-order kinetic model, indicating the involvement of reactive oxygen species in the degradation mechanism. The present work provides adsorbent catalyst with simple synthetic process, high adsorption capacity, efficient catalytic activity, high reusability and stability, which demonstrates the potential use for removing organic pollutants in wastewater. • This manuscript presents a novel and eco-friendly method for preparing carbon-silica modified calcium aluminosilicate nanoparticles using waste coal ash as a sustainable precursor. • The synthesized composite exhibits exceptional adsorption capabilities for methylene blue, a common organic dye pollutant. • Carbon-silica modified calcium aluminosilicate nanoparticles also can degrade methylene blue via advanced oxidation process. • The use of waste coal ash in this process not only provides a cost-effective solution for waste management but also contributes to the development of environmentally friendly materials.