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Titanium dioxide (TiO2) in different forms such as films, fibers or particles are being extensively studied for removal of contaminants from aquatic environments due to its outstanding photocatalytic activity. This work reports the development of TiO 2 -polyamide 12 electrospun fiber mats. A systematic study on the influence of electrospun processing parameters on polymer fiber morphology was performed. It was observed that the average fiber diameter is mainly influenced by polymer concentration and average fiber diameters between 404 ± 82 nm and 1442 ± 360 nm were obtained. Polyamide-12 (PA-12) was used as a polymer matrix and electrospun with 0, 10 and 20 wt% of TiO 2 . It was observed that the filler does not change the average fiber diameter, being similar to that observed for neat PA-12 fibers processed under the same experimental conditions. The TiO 2 were particles dispensed not only in the bulk of the polymeric matrix but also on the surface of the fibers, especially for the samples with higher filler contents. Neat and nanocomposite electrospun samples show a hydrophobic behavior and a degree of crystallinity of ~25%. The photocatalytic performance of the processed samples was measured by following the degradation capability of a chosen dye, methylene blue (MB). Results show that the nanocomposite samples have a remarkable photocatalytic activity, especially the one with a higher load of TiO 2 particles (20 wt%), with all MB being removed from the solution after 100 min. AbstractTitanium dioxide (TiO 2 ) in different forms such as films, fibers or particles are being extensively studied for removal of contaminants from aquatic environments due to its outstanding photocatalytic activity. This work reports the development of TiO 2 -polyamide 12 electrospun fiber mats. A systematic study on the influence of electrospun processing parameters on polymer fiber morphology was performed. It was observed that the average fiber diameter is mainly influenced by polymer concentration and average fiber diameters between 404±82 nm and 1442±360 nm were obtained.Polyamide-12 (PA-12) was used as a polymer matrix and electrospun with 0, 10 and 20 wt% of TiO 2 . It was observed that the filler does not change the average fiber diameter, being similar to that observed for neat PA-12 fibers processed under the same experimental conditions. The TiO 2 were particles dispensed not only in the bulk of the polymeric matrix but also on the surface of the fibers, especially for the samples with 2 higher filler contents. Neat and nanocomposite electrospun samples show a hydrophobic behavior and a degree of crystallinity of ~ 25%.The photocatalytic performance of the processed samples was measured by following the degradation capability of a chosen dye, methylene blue (MB). Results show that the nanocomposite samples have a remarkable photocatalytic activity, especially the one with a higher load of TiO 2 particles (20 wt%), with all MB being removed from the solution after 100 min.

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Environmental problems that result from increases in the generation of urban solid waste are compounded by the inadequate management of wastes generated by large-scale meal production at Food and Nutrition Units (FNUs). With the growth of eating out sector, solid waste management of FNUs should be focused on minimizing waste generation, while considering all regulations enforced, including those related to hygienic quality of food. The goal of this study was to determine the quantities and types of waste generated by a university cafeteria in Brazil to help implement a solid waste management plan that adhered to the Brazilian National Policy on Solid Waste. For this purpose, the waste generated during each stage of the meal production process was weighed according to its type for 21 days. Additionally, structured observations were conducted to identify adopted waste management practices and further opportunities for waste reduction at the facility. During this study, 6,553.5 kg of waste was generated, of which 82.6% resulted from organic food waste and 17.4% resulted from recyclable and other residual waste. Based on the collected data and structured observations, certain recommendations were provided for reducing the waste generated during cafeteria processes and for modifying the cafeteria activities to meet environmental and hygienic-sanitary requirements. The analysis presented in this study could guide the implementation of waste management plans in similar establishments that seek sustainability in meal production and that intends to comply with current legislation.

The adsorption of two metal ions, Cr(III) and Cu(II), in single-component and binary systems by Sargassum sp., a brown alga, was studied. Equilibrium batch sorption studies were carried out at 30ºC and pH 3.5. Kinetic tests were done for a binary mixture (chromium + copper) for a contact time of 72 hours to guarantee that equilibrium was reached. The monocomponent equilibrium data obtained were analyzed using the Langmuir and Freundlich isotherms. The binary equilibrium data obtained were described using four Langmuir-type and Freundlich isotherms. The F-test showed a statistically significant fit for all binary isotherm models. The parameters for isotherms of the Langmuir-type were used to determine the affinity of one metal for the biosorbent in the presence of another metal. The chromium ion showed a greater affinity for Sargassum sp. than the copper ion

Hospitals consume a large volume of water to carry out their activities and, hence, generate a large volume of effluent that is commonly discharged into the local sewage system without any treatment. Among the various sectors of healthcare facilities, the laundry is responsible for the majority of water consumption and generates a highly complex effluent. Although several advanced oxidation processes (AOPs) are currently under investigation on the degradation of a variety of contaminants, few of them are based on real wastewater samples. In this paper, the UV/HO AOP was evaluated on the treatment of a hospital laundry wastewater, after the application of a physicochemical pretreatment composed of coagulation-flocculation and anthracite filtration. For the UV/HO process, a photoreactor equipped with a low-pressure UV-C lamp was used and the effects of initial pH and [HO]/chemical oxygen demand (COD) ratio on COD removal were investigated through a randomized factorial block design that considered the batches of effluent as blocks. The results indicated that the initial pH had no significant effect on the COD removal, and the process was favored by the increase in [HO]/COD ratio. Color and turbidity were satisfactorily reduced after the application of the physicochemical pretreatment, and COD was completely removed by the UV/HO process under suitable conditions. The results of this study show that the UV/HO AOP is a promising candidate for hospital laundry wastewater treatment and should be explored to enable wastewater reuse in the washing process.