Fotodegradação de efluentes têxteis catalisada por Zn0

• Ano de defesa: 2009
• Autor(a) principal: Ribeiro, Valquíria Aparecida dos Santos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual de Maringá; Brasil; Programa de Pós-Graduação em Engenharia Química; UEM; Maringá, PR; Departamento de Engenharia Química
• Palavras-chave em Português: Fotodegradação catalítica; Efluente têxtil; Catalisada por ZnO; Lavanderia industrial; Tratamento; Corante têxtil; Reator tipo lama; Resíduos sólidos; Processos oxidativos avançados; Brasil.; Catalytic photodegradation; Textile effluent; Industrial laundry; Zno; Brazil.; Engenharias; Engenharia Química
• Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/3766

Contamination of the environment in recent decades has been identified as one of the major problems of society. Given that companies have assumed a new attitude towards environmental issues. The textile industry, which is one of the major water consumers, and consequently, a large generator of wastewaters, is one of the industries that have sought to modify its stance on these problems. Conventional treatments of textile effluents based on physico-chemical methods followed by biological processes have proved to be unsatisfactory for the removal of color of these effluents. Thus, studies on catalytic photodegradation have gained prominence due to its ability to decolorize effluents and to degrade recalcitrant compounds. This process is based on the excitation of a semiconductor by UV radiation (natural or artificial), to promote an electron from the valence band to the conduction band, forming pairs of electronsgaps, which are capable of oxidizing and reducing organic compounds. This thesis aims to contribute to the discussion of this important subject, by evaluating the application of the ZnO semiconductor in photo-oxidative process for the treatment of effluent from an industrial laundry into the region of Maringá, under bench and semipilot scale. The pH, color, turbidity, COD, BOD and metals were the parameters used for the evaluation of the treatment process. Through the tests can determine the pH 4.0 and the concentration of 3 g / L of catalyst are the parameter that showed better results for the color removal of wastewater tested. Overall the process has proved satisfactory for most of the parameters, not only meeting the expectations in the issue metals. Due to the solubility of the catalyst, zinc was detected in concentrations above the permitted limit. The process of catalytic degradation of wastewater from industrial laundries, therefore, was effective in the remediation of effluents in both bench scale and in semi-pilot scale. Given the environmental laws regarding the removal of color, COD and BOD as well as maintaining the pH within the range established in the legislation, but excess zinc dissolved in the effluent requires a method of further processing for its removal before disposal. In addition, the solid waste generated in the treatment process, which is basically the catalyst after use, it was classified, according to NBR 10004, the Brazilian Association of Technical Standards (ABNT), as hazardous waste due to the presence of lead in its constitution, hus necessitanting treatment and disposal in industrial landfills for such class.