Eco-Friendly Biosorption of Uranium from Aqueous Solutions Using Sepiolite-Cavex CA37 Composite Biosorbent

Abstract

Cavex CA37 is a dental material used for positive tooth impressions. After the mold is taken, it hardens through a fast-chemical reaction with air, then becomes waste after usage. In this study, natural sepiolite and Cavex CA37 are mixed at certain ratios to obtain a composite SCX-37 biosorbent that is used for the biosorption of UO2+ (2) ions from a synthetic aqueous solution. Parameters affecting biosorption, such as solution pH, ambient temperature, contact time, and UO2+ (2) ion concentration, are investigated. The biosorption of UO2+ (2) ions on SCX-37 reaches equilibrium in 120 min with 97.56% efficiency at 30 degrees C and pH 4. The isotherms (Langmuir, Freundlich, and D-R) and thermodynamic values of the biosorption of UO2+ (2) ions on the SCX-37 biosorbent are calculated according to the obtained data. It is determined that there is a high correlation between experimental results and all three isotherm models. The adsorption capacity is found to be 41.39 mg g(-1). The biosorption of UO2+ (2) ions onto the SCX37 biosorbent is a chemisorption process with an adsorption energy of 40.50 kJ mol(-1).