This article presents results on the synthesis, characterization, and application of ferrites encapsulated by titanium dioxide as a catalyst for the photodegradation of azo dyes and color removal of textile effluents. X-ray diffraction and scanning electron microscopy (SEM)/energy dispersive systems (EDS) results showed that encapsulation was effective, yielding a nanocomposite with a magnetic core and photoactive surface. Photocatalytic tests carried out with azo dye blue HFRL and with textile effluents showed that in the presence of encapsulated ferrites, color removal was enhanced with both low- and high-energy lamps. Photocatalysis of textile effluent led to the removal of anionic surfactants but did not result in chemical oxygen demand removal; nevertheless, it enhanced the aerobic biodegradability of the textile effluent, mainly when ultraviolet light was used. Mass spectrometry data showed that chemical profiles of intermediates accumulated in solution after photocatalysis depended on the type of radiation used, corroborating the biodegradability tests.
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