Estudo da ferrita CuFe2O4 como catalisador heterogêneo na degradação de Rodamina B

Abstract

The Fenton process, one of the main advanced oxidative processes (AOP’s), has been widely used in the degradation and mineralization of organic contaminants in waters, since it consists of a simple process, with relatively low cost, easy operation (atmospheric pressure and temperature environment) and high oxidation rate. The heterogeneous Fenton process, however, has been further studied lately as it presents advantages such as the removal of the catalyst from the medium after the process, as well as the reusability in other catalytic cycles. The CuFe2O4 ferrite was used as a heterogeneous Fenton-like catalyst to promote the degradation of rhodamine B (RB), an important cationic xanthene dye, widely used in the textile industry and has become a common pollutant, its release into the environment causes chronic toxicity in both humans and animals. The catalytic system was constituted by dye solution, CuFe2O4 as a heterogeneous catalyst, H2O2 as a generator of HO● radicals (when activated by the metal ions present in the ferrite) and hydrazine (N2H2) to accelerate the redox cycle of these metals. The results showed that the degradation of rhodamine B in this system reached an efficiency > 99% after 20 min of reaction. Due to its magnetic properties, CuFe2O4 was easily removed from the system after the reactions and reused for another four cycles without significant loss of catalytic activity.