CHARACTERIZATION-PERFORMANCE OF ZnO AND ZnO/ZnFe₂O₄ CATALYST USING ARTIFICIAL AND SOLAR LIGHT FOR MERCURY (II) REDUCTION

Abstract

This study describes the application of ZnO commercial oxide and ZnO/ZnFe₂O₄ mixed oxides to reduce the mercury ion (Hg²⁺) in the aqueous phase. The catalysts synthesized were characterized by thermogravimetric analysis, adsorption and desorption of N₂, scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, photoacoustic spectroscopy and Mössbauer spectroscopy. The heterogeneous photocatalysis process was studied in synthetic effluent treatment containing mercury chloride (HgCl₂) in a batch and solar reactor. The results indicated that commercial ZnO catalyst totally reduced the Hg (II), in all conditions and reaction systems studied. On the other hand, for the mixed oxides (ZnO/ZnFe₂O₄), there was a decrease in the reduction efficiency in the batch reactor, indicating no ability to reduce Hg(II) in the presence of sunlight.

Keywords:
Mercury Reduction; Zinc ferrite; Zinc oxide; Heterogeneous photocatalysis