RESUMO
This paper presents an exploratory study of pulp mill bleaching effluent treatment by a biological-photocatalytic coupled system. A fungus, Trametes pubescens, immobilized on polyurethane foam was used to inoculate the biological pre-treatment system. The pretreated effluent was then exposed to a photocatalytic treatment in which two catalysts (TiO(2) and ZnO) and two supports (aluminum foil and Luffa cylindrica) were tested. Catalyst characterization was carried out by means of X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Information about crystalline structure, chemical composition, morphology, homogeneity and distribution on the support surface area was obtained. The overall biological-photocatalytic coupled system achieved degradation of 96% of initial total organic carbon (TOC), 97% of 2-chlorophenol (2-CP), 90% of 2,4-dichlorophenol (2,4-CP) and 99% of 2,4,6-trichlorophenol (2,4,6-TCP). This approach of synergistic coupling of T. pubescens and a semiconductor photocatalyst appears to be a viable alternative for the treatment of these non-biodegradable effluents.
Assuntos
Titânio/química , Raios Ultravioleta , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Óxido de Zinco/química , Biodegradação Ambiental , Catálise , Clorofenóis/química , Clorofenóis/metabolismo , Trametes/metabolismo , Poluentes Químicos da Água/metabolismoRESUMO
Con la creciente presión hacia un uso más racional del recurso hídrico, el desarrollo de tecnologías apropiadas de tratamiento de aguas es cada vez más urgente. Debido a ello, en los últimos años se han propuesto procesos de oxidación fotoquímicos y electroquímicos como alternativa para el tratamiento de aguas contaminadas con sustancias antropogénicas difícilmente biodegradables, así como para eliminar bacterias en aguas destinadas al consumo humano. El objetivo de este trabajo es presentar algunas de nuestras más recientes investigaciones que demuestran que tanto la electroquímica como la fotoquímica, al igual que el acople de estos procesos con tratamientos biológicos, son alternativas muy prometedoras para aumentar la calidad del agua.
With the increasing pressure on a more effective use of water resources, the developpement of appropriate water treatment technologies become more and more important. Photochemical and electrochemical oxidation processes have been proposed in recent years as an attractive alternative for the treatment of contaminated water containing anthropogenic substances hardly biodegradable as well as to purify and disinfect drinking waters. The aim of this paper is to present some of our last results demonstrating that electrochemical, photochemical, and the coupling of these processes with biological systems are very promising alternativesfor the improvement of the water quality.