Mestrado em Química (IQ)
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Item Tratamento químico de poluentes emergentes da indústria cosmética utilizando materiais de baixo custo(Universidade Federal de Goiás, 2019-09-06) Andrade, Pryscilla Martins de; Brito, Núbia Natália de; http://lattes.cnpq.br/9075769086344855; Ionashiro , Elias Yuki; Arruda , Andréa Fernandes; Brito, Núbia Natália deThe cosmetics industry presents a variety of products that contain numerous organic structures, which once in contact with water, release effluents with low biodegradability, high organic load, high levels of suspended solids, fats and oils. These effluents, when subjected to conventional (isolated) treatment at sewage treatment plants, based mainly on microbiological degradation, are not treated efficiently, leaving significant concentrations of emerging pollutants at the end of the treatment. As an alternative for effluent treatment from the cosmetics industry, advanced oxidation process (AOP) treatment technologies, which involve the generation of hydroxyl radical (•OH), with a 2.8 V potential redox, are interesting because present mineralization capacity of organic matter. Among them, the photo Fenton Like process is promising, as it has as its differential the feasibility of harnessing solar energy as a source of radiation and the utilization of by-products from the steel/metallurgical industry, besides providing the lowest generation of sludge. In this work, the photo Fenton Like treatment was proposed for the cosmetic effluent, using as source of iron, metallurgical residue, and as radiation source, light-emitting diode lamps (LED) and the construction of a recirculating photocatalytic reactor. An integration of technologies was proposed as the final polish using a filter built with layers of agro-industrial waste (rice husks, vermiculite and carbonized corn cob). The acid-washed metallurgical residue had about 96% iron oxide III in its composition, confirming its viability for the application of the heterogeneous photo Fenton Like process. Under the conditions of metallurgical residue with acid wash (HCl) in dosage of 8 g L-1, H2O2 in 0.05 g L-1, effluent with pH 3.0 adjustment and time of 6 minutes, the advanced oxidative treatment provided 99.25% chemical oxygen demand removals and 75.73% total organic carbon. Thermogravimetric analysis of the chemical sludge revealed the presence of 14% by mass of organic matter in the metallurgical residue, indicating that most of the organic matter present in the cosmetic matrix was oxidized. Infrared spectroscopy analysis found that the small amount of material adsorbed and possibly related to paraffin. With the combined process, advanced oxidation by heterogeneous photo Fenton Like and slow filtration, it was possible to achieve an overall removal of 99.48% COD with a final value of 255.98 mgO2 L-1, which meets the required state parameters for disposal in water sources. Through these results, the integration of the treatment technologies proved to be satisfactory for the remediation of this recalcitrant matrix, since high removal of the organic matter parameter values was achieved, which may be indicative of the possibility of integration with the treatment technologies conventional.Item Tratamento via reação de fenton de efluente cosmético da linha de produção de filtro solar(Universidade Federal de Goiás, 2015-09-30) Morais, Weberson de Oliveira; Brito, Núbia Natália de; http://lattes.cnpq.br/9075769086344855; Brito, Núbia Natália de; Arruda, Andréa Fernandes; Longhin, Sandra ReginaAdvanced oxidation processes are consolidated technologies when it comes to treatment of industrial wastewater. Such processes are based on the generation of the hydroxyl radical (• HO), with high potential to oxidize organic matter (2,8eV). These, because they are poorly selective and highly reactive, oxidize the organic matter from promoting an increase in the biodegradable fraction to a possible complete mineralization of the contaminant in the wastewater. Among the advanced oxidation processes, the Fenton’s reagent stands out for its simplicity, low treatment time and low economic value. This reaction proceeds by catalytic decomposition of hydrogen peroxide (H2O2), in acid pH, by oxidizing Fe+2 to Fe+3 with the subsequent generation of the hydroxyl radical. In the Fenton’s reaction, some intermediate reactions give a unique characteristic to the process during the treatment which stand out hydrolysis of Fe+2 and Fe+3 forming a series of aqueous ferrous and ferric complexes which enable the occurrence of Process coagulation / flocculation with subsequent formation of sludge. The integration of these two technologies confers the treated wastewater a significant increase in contaminant removal, because, from this stage, the process of sedimentation, there is the drag of a large amount of non-degraded organic matter via chemical oxidation, in the form of sludge. In this work the application of integrated Fenton’s reaction to coagulation / flocculation in the treatment of cosmetic wastewater sunscreen lotion production line. The treatment was performed at Jar Test equipment with one liter volume: carried out rapid mixing at 300 rpm for 20 seconds after the addition of ferrous sulfate heptahydrate, subsequently slow mixing at 30 rpm for 6 minutes and 10 seconds after the addition of hydrogen peroxide. After this sequence, each test was allowed to rest on sedimentation for 60 minutes. The entire process took place at ambient temperature. At first the treatment was executed in a simulated wastewater from a sunscreen acquired in a cosmetics industry in the metropolitan area of Goiânia. After optimization of the concentration of 22,12 mgL-1 Fe+2, 500 mgL-1 H2O2 and pH 4.0, we observed a reduction of 82.56% in the chemical oxygen demand (COD) , 97.33% and 98.00% in turbidity in absorbance which indicated a high efficiency of the treatment in regard to an adjustment to CONAMA Resolution 430 2011. Other parameters were analyzed in order to obtain reliable information about the proposed treatment, and a reduction of 91.49% of Total Organic Carbon (TOC), 99.67% of oils and greases, 98.81% of total suspended solids (TSS), 73.05% of surfactants and 64.68 % of total phenols. The total treatment time was 226 minutes and 30 seconds. With these removal treatment with the actual wastewater was considered extremely efficient for a possible application of this methodology in the industrial segment, it should be observed that when applied in an isolated way, the advanced oxidation processes do not have good efficiency, however, in this study the treatment means Fenton’s reaction integrated technology coagulation / flocculation has a high capacity for a full-scale application in the cosmetic segment.