In this work, MCM-41, magnetite (MAG), and a composite of magnetite and MCM-41 (MCM-MAG) were synthesized by a simple route for the production of active systems in the decomposition of organic waste. The materials were characterized by N2 adsorption/desorption, X-ray diffraction analysis (XRD), temperature programmed reduction (TPR), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Our results indicated that the decolorization kinetics of the dyes were in the order of MCM-MAG > MCM-41 > magnetite. Mineralization of the dyes was monitored by total organic carbon (TOC) decrease. The dye solutions could be completely decolorized and effectively mineralized, with an average overall TOC removal 43% for a Fenton-like reaction time of 180？min. The degradation activity of the MCM-MAG was stable during four consecutive experiments, confirming their stability and reusability of the composite. The great advantage of this composite is that it may be easily magnetically recovered and reused. 1. Introduction Currently the efficient use of water is important for industry, as it is crucial for sustainable development and public health. In many cases the generation of contaminated effluents with various types of organic waste, which are rich in microbial or bacterial activity, are involved. This is not appropriate for reuse in agriculture and human consumption [1]. With regard to organic pollutants, we can highlight the textile dyes, which possess a high capacity to modify the environment due to their strong color and visual pollution and also cause changes in biological cycles mainly affecting photosynthesis processes. Besides these facts, studies have shown that some classes of dyes and their byproducts may be carcinogenic and/or mutagenic [2]. In this context, the development of new processes for wastewater treatment in order to immobilize or degrade these compounds in textile industry effluents is very important. An extensively studied alternative is the use of advanced oxidation processes (AOP). These processes are based on the formation of hydroxyl radicals, which are capable of oxidizing contaminants to smaller and less polluting molecules or even mineralize them, turning them into CO2, H2O, and inorganic ions from atoms [3]. The development of active heterogeneous systems to promote Fenton chemistry is of considerable interest, since it could offer some advantages over the classical homogeneous Fenton; because there is no sludge formation, the operation is carried out in near neutral pH and there is the possibility of
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