Degradação de rodamina B: uma avaliação do efeito catalítico de íons Fe e Cu suportados em sílica

Abstract

Pollution of water bodies caused by disposal of industrial effluents is a problem of worldwide concern. Conventional water treatments such as filtration and coagulation are not able to treat water contaminated with non-biodegradable pollutants as are most dyes. Advanced oxidation processes (AOPs) are an alternative to conventional treatment methods and have shown to be promising in the degradation of organic pollutants. Among the OAPs are stand out Fenton process, using iron as catalyst, and Fenton-like process, using iron and/or a second metal in the catalytic process. Due to their simplicity, fast kinetics and low cost, these processes have been widely used to degrade organic pollutants. Thus, in this work, bimetallic catalysts were prepared containing different iron contents and 1% (w/w) of copper supported in silica. These materials were characterized by X-ray diffraction, atomic absorption spectrometry, temperature programmed reduction and N2 adsorption–desorption isotherms. The catalytic performance of these materials was evaluated in the degradation of Rhodamine B, via Fenton-like process. The results showed that the catalytic activity depends on the concentrations of iron and that the addition of copper results in a higher catalytic efficiency. In particular, the catalyst with the lowest iron content showed better catalytic efficiency and was able to degrade 98% of the dye within 30 min at pH 7. The results are promising since textile effluents have high pH values in general. In addition, the catalyst showed good catalytic activity, even after five consecutive runs.