Tratamento de efluente da indústria de cosméticos via reagente de Fenton e adsorção

• Ano de defesa: 2018
• Autor(a) principal: Pereira, Lisiée Manzoli Gonçaves
• Orientador(a): Ostroski, Indianara Conceição
• Banca de defesa: Ostroski, Indianara Conceição, Brito, Núbia Natália de, Seollato, Araceli Aparecida, Schneider, Roselene Maria
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Programa de Pós-graduação em Engenharia Química (IQ)
• Departamento: Instituto de Química - IQ (RG)
• País: Brasil
• Palavras-chave em Português: Integração de tecnologias; Parâmetros ambientais; Caracterização física e química; Processos oxidativos avançados
• Palavras-chave em Inglês: Technology integration; Environmental parameters; Physical and chemical characterization; Advanced oxidation processes
• Área do conhecimento CNPq: ENGENHARIA QUIMICA::TECNOLOGIA QUIMICA
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/8452

The effluent generated by the cosmetic industries, from industrial processes, tank washes and disposal of failed batches, are highly recalcitrant due to their complex chemical composition. The deposition of such liquids into water bodies must follow a series of environmental parameter values established by local and federal legislation so that they do not negatively affect the receiving environment and its ecosystems. Traditional wastewater treatment methods sometimes fail to satisfactorily remove their contaminating potential. Therefore, this work aims at integrating two treatment technologies, Fenton’s reagent and adsorption, in order to achieve maximum removal efficiency in the values of environmental and water quality control parameters. Wastewater from a cosmetics industry in the metropolitan area of Goiania (state of Goias, Brazil) was used as object of this study. The environmental parameters analyzed were: color (via absorbance analysis), total iron, organic matter (via chemical oxygem demand analysis), total phenols, pH, turbidity, conductivity, dissolved oxygen, initial and residual H2O2 and total solids. They were analyzed on the pretreated wastewater, after the Fenton’s reagent treatment, after adsorption, and after the combined processes. The adsorbent was characterized by elemental analysis (CHN), thermogravimetry (TG/DTA), adsorption and desorption of N2 and infrared spectroscopy. In the Fenton’s reagent treatment, factorial design 23 was performed for the factors: Fe2+ and H2O2 concentrations and pH, in order to outline the process parameters. From these data, other Fenton assays were performed by opening Fe2+, H2O2 and pH concentration bands to evaluate their influence on the removal of the environmental parameters mentioned above. The best results were obtained in Fe2+ 184.21 mg L-1; H2O2 concentration at 1300 mg L-1, and pH at 3.5. Subsequently, the wastewater treated via Fenton’s reagent was subjected to the adsorption process, in which seven types of activated carbon were tested. The activated charcoal which presented the best efficiency at removing environmental parameter values was submitted to kinetic tests at different temperatures and contact times. The equilibrium time was reached in 16 minutes (tested in the range of 4min to 24h), and for the different temperatures it was observed that its increase did not contribute significantly to the process efficiency (tested in the range of 20 to 60ºC). The integration of the two technologies presented the following percentages of global variation: chemical oxygem demand: -73.58%; turbidity: -97.65%; conductivity: -5.36%; dissolved oxygen: + 141.24%; total phenols: -81.77%; total iron: -69.97%; hydrogen peroxide: -97.78%; total solids: -46.37%; total fixed solids: -30.57%; total volatile solids: -46.65%; absorbance at 200 nm: -36.38%; absorbance at 400 nm: -77.37%. The pH, total iron and hydrogen peroxide parameters were controlled in the Fenton’s reagent process.