| Abstrakt: |
A large amount of contaminated industrial wastewater has aroused mounting concern by researchers and environmentalists. Dyes contained in industrial effluents are often quite persistent to biodegradation, which must be treated before being disposed of. In this context, the use of Fenton processes is a potential alternative to treat a wide range of dyes and other organic pollutants found in wastewater. Thus, several Fe2O3/MCM‐41 catalysts have been synthesized in the following molar ratio of SiO2/Fe2O3: 10, 20, 40, 100, and 200. They were characterized by N2 adsorption–desorption isotherm, X‐ray fluorescence (XRF), X‐ray diffraction (XRD), UV–vis spectroscopy and H2 temperature‐programmed reduction (H2‐TPR), and applied to degrade methyl orange dye (MO) via a heterogeneous Fenton reaction. Catalytic tests revealed that SiO2/Fe2O3 = 10 reached the highest activity due to greater availability of active sites which generated a larger quantity of hydroxyl (•OH) and perhydroxyl (•OOH) radicals. Furthermore, 70% of color removal has been achieved after 120 min at room temperature. Moreover, the systems moderately enhanced organic matter mineralization according to chemical oxygen demand (COD) testing. There was also catalytic activity loss in consecutive reaction cycles, which is probably due to dye molecules adsorption on active sites. [ABSTRACT FROM AUTHOR] |
Plný text