Halloysite-based materials used for lead ions removal from wastewater
Stoian Oana, Fleaca Teodor Claudiu, Covaliu Cristina Ileana
Politehnica University of Bucharest, Faculty of Biotechnical Systems Engineering
Water pollution with heavy metals, such as Pb (II), Cu (II), Cd (II), Mn (II), Cr (IV) and others, is induced by fast industrialization and urbanization and, due to their toxicity, they pose a significant threat to human health. Adsorption is an efficient process used for wastewater treatment [1, 2] and has been used successfully in the experiments presented below to remove lead ions from wastewater. The advantages of applying the adsorption process for wastewater treatment are represented by the availability, profitability, low cost, high efficiency and ease of operation [3, 4, 5]. Halloysite nanotubes have been successfully applied in the process of removing heavy metals from wastewater by adsorption .
In order to remove lead ions from synthetic wastewater, seven composite materials consisting of halloysite nanotubes - HNTs, mainly and, in addition, polyaniline - PANI, partially reduced graphene oxide - PRGO, polypyrrole - Pry, cobalt chloride - CoCl2, prussian blue dye, cobalt ferrite - CoFe2O4, sodium and calcium alginate - CaNaAlg were researched. Following the experimental results, maximum treatment efficiencies were obtained using PRGO Pry HNT CoCl2 and Halloysite CoFe2O4, but the time required to remove lead ions from wastewater was different, namely 540 and 270 minutes, respectively.
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