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Submerged Membranes Bioreactors (SMBR) are an established technology for wastewater treatment for water recovery and reuse. However, its routine application is still compromised by the high energy consumption to overcome the fouling effect. This study evaluated the effect of aluminum sulfate and cationic polymer in the orthophosphate removal and sludge filterability improvement in the mixed liquor of a SMBR pilot system. Parameters such as coagulant concentration, filtration time, extracellular polymeric substances (EPS) reduction and orthophosphate removal were evaluated by using a jar-test and a stirred cell. As results, aluminum sulfate and polymer additions improved the filtration index (FI 30) from 25% to 32 %, for both chemicals. Timeto-filter (TTF) results evidenced a positive and significant correlation between aluminum sulfate dosage and colloidal EPS reduction.

Carbon materials are widely used as supercapacitor electrodes while iron oxides and other iron compounds are promising electrode materials due to its pseudocapacitive contribution. This work deals with the preparation and electrochemical characterization of iron/carbon composites for supercapacitor electrode applications. The carbon precursor samples were prepared from a carbonization of babassu coconut endocarp, and the iron/carbon nanocomposites were obtained by precipitation synthesis using iron salt, followed by a heat treatment at different temperatures. The electrochemical characterization of the samples show that, at low current density, the sample without iron compounds shows the higher electrical capacitance, up to 98 F g-1 in 2 M H2SO4. This good performance can be associated to a pseudocapacitive contribution of the oxygenated functional groups present in this sample. However, at higher current densities, the best electrochemical behaviour was achieved for the sample treated at 1000 °C. This good performance is may be associated to the Feº and Fe3C nanoparticles present in the sample which can enhance its electrical conductivity. On the other hand, is no there clearly evidence of pseudocapacitive contribution of the iron particles. Future works will seek to improve the surface area of the materials with the aim to increase the double layer capacitance, and also to perform electrochemical studies using other electrolytes.

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