Adsorção de selênio presente em água utilizando hidróxido duplo lamelar lítio-alumínio magnético

Abstract

This study evaluated the synthesis and characterization of the layered double hydroxide-coated magnetite particles based on lithium and aluminum. The solids were characterized by FTIR, XRD, nitrogen physisorption and determination of Point Zero Charge in order to determine the dependence of surface charge on pH of the solution. The adsorption ability of the magnetic particles was evaluated in batch experiments for selenate ion removal from aqueous solution. Therefore, a series of parameters was studied such as temperature, time contact, pH and mass of magnetic particles. The results pointed out to an interesting adsorption capacity for selenate ions, removing approximately 98% of selenate from aqueous solution. Results showed maximum adsorption capacity (qm) of 4.98 mg.g-1 and the adsorption isotherms were well adjusted using Langmuir and Freundlich models. Adsorption process follows pseudo-second-order kinetic model with a rate constant of 3.42 g.mg-1.min-1.