In this work, cobalt ferrite (CoFe 2 O 4) was synthesized by solvothermal route for application as a catalyst in the ozonation reaction for the decolorization and mineralization of melanoidin from aqueous solution. The structural properties of CoFe 2 O 4 sample were investigated by X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FTIR), particlesize distribution, scanning electron microscopy (SEM) and X-ray dispersive energy spectroscopy (EDS). Single-phase CoFe 2 O 4 particles with a predominantly mesoporous structure containing a high specific surface area were obtained. Results showed that the CoFe 2 O 4-catalyzed ozonation reaction has higher activity for the decolorization and mineralization of melanoidin when compared with the ozonation reaction without the presence of catalyst. Therefore, this material can be very promising for the application in catalytic ozonation systems for the melanoidin removal from liquid effluents.

Mesoporous Fe 2 O 3 -supported ZSM-5 zeolites were prepared by carbon-templating and subsequently evaluated as photo-Fenton catalysts to degrade a dye used as a model heavy organic pollutant. The synthesis procedure of the mesoporous ZSM-5 zeolites was performed employing a nucleating gel and carbon particles as mesopores template. Thereafter, the precursor salt of the iron oxide (Fe 2 O 3 ) was impregnated and then calcined to obtain the final catalyst. For comparison purposes, a conventional Fe 2 O 3 -supported ZSM-5 zeolite was also prepared. The results showed that the amount of intracrystalline mesopores formed in the ZSM-5 crystals was influenced by the amount of carbon added into the synthesis mixture. In comparison to the conventional prepared catalyst, the mesoporous Fe 2 O 3 /ZSM-5 ones showed an improved performance in the degradation of the target organic pollutant by the photo-Fenton reaction, which was attributed to the improvement of their textural properties as consequence of the mesopores generation.

ResumoEste trabalho objetivou a preparação da zeólita ZSM-5 suportada com nanopartículas de óxido de ferro para uso como catalisador na degradação de um poluente orgânico em solução aquosa a partir do processo foto-Fenton. A zeólita foi preparada usando gel nucleante como indutor de formação da estrutura tipo MFI. Nanopartículas de óxido de ferro foram suportadas sobre a zeólita através da técnica de impregnação incipiente. Além disso, nanopartículas de óxido de ferro foram preparadas para fins de comparação entre as atividades catalíticas na reação foto-Fenton. Os materiais produzidos foram caracterizados por difração de raios X, microscopia eletrônica de varredura e análise de adsorção/dessorção de nitrogênio. Os resultados revelaram a formação do sistema Fe 2 O 3 /ZSM-5 com propriedades intrínsecas que resultaram em satisfatória atividade catalítica, sendo superior ao óxido de ferro. Além disso, esse sistema apresentou excelente atividade e estabilidade após três ciclos de reuso. O material Fe 2 O 3 /ZSM-5 produzido neste trabalho apresenta-se como um catalisador promissor para uso na reação foto-Fenton para a degradação de poluentes orgânicos em soluções aquosas. Palavras-chave: síntese, ZSM-5, Fe 2 O 3 , Fe 2 O 3 /ZSM-5, foto-Fenton. Abstract The aim of this work was to prepare ZSM-5 zeolite-supported iron oxide nanoparticles for use as a catalyst in the degradation of an organic pollutant in aqueous solution through the photo-Fenton process. ZSM-5 zeolite was prepared using nucleation gel to induce

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