Zeolite Materials Obtained from Fly Ash Used for Removal of Heavy Metals and dye from Complex Wastewaters

摘要

Annually huge amounts of fly ash are produced,instead of land filling this waste can be reutilized for obtaining new materials such as zeolites which can be further used in adsorption processes.The fly ash,collected from Power Plant Craiova(Romania)was used for obtaining the zeolites materials with good adsorption capacity for heavy metals and dyes from wastewater.Fly ashes hydrothermally treated were used as a low cost adsorbents for the removal of Cd2+,Cu2+ cations and Methylene blue(MB)from synthetic wastewaters containing one,two and three pollutants.The new zeolite materials(ZCRns and ZCRs20)obtained from fly ash Craiova(FACR)has an increased specific surface area which led to good efficiencies.During the adsorption process the parameters: contact time and optimum amount of substrate were optimized for obtaining a maximum efficiency.The adsorption isotherms and kinetics were studied.The obtained results were fitted using Langmuir and Freundlich isotherms.Pseudo-first order,pseudo-second order and interparticle diffusion were employed for analyzing the kinetic data.The new material was characterized in terms of crystallinity(XRD)and surface properties: morphology.The composite substrate proved good efficiencies for removal of heavy metals cations and methylene blue from the synthetic pollutant systems in adsorption.As the results show,MB removal runs with the highest efficiency in adsorption(93.33%)while heavy metals removal has almost similar values in adsorption processes.