TiO2 photocatalytic inactivation under simulated solar light of bacterial consortia in domestic wastewaters previously treated by UASB, duckweed and facultative ponds

Abstract

Recebido em 28/8/09; aceito em 23/4/09; publicado na web em 9/8/10In this work, TiO 2 photocatalysis was used to disinfect domestic wastewaters previously treated by different biological treatment systems: Upward-flow Anaerobic Sludge Blanket (UASB), facultative pond, and duckweed pond. The microorganisms monitored were E. coli, total coliforms, Shigella species, and Salmonella species. Photocatalytic experiments were carried out using two light sources: a solar simulator (UV intensity: 68-70 W m ). Samples were taken after each treatment stage. Results indicate that bacterial photocatalytic inactivation is affected by characteristics of the effluent, including turbidity, concentration of organic matter, and bacterial concentration, which depend of the type of biological pretreatment previously used.

Enhanced photocatalytic activity of TiO2 films by modification with polyethylene glycol

“…Given these characteristics, TiO 2 is the most commonly employed material in photocatalytic applications. [1][2][3] Several techniques have been employed in the fabrication of TiO 2 thin films: Sputtering, 4 electrophoretic deposition, 5,6 sol-gel deposition, 7 and spray pyrolysis, 8 to cite the most common. Amongst these, the sol-gel route is the widest used, due to the low sintering temperatures required, process versatility and homogeneity at the molecular level.…”

Dynamics of the TiO<sub>2</sub> nanofilms bactericidal activity

“…ROS attacks the cell wall of bacteria adhered on surface or contact with surface and as a result of oxidation the bacterial components the microorganisms are destroyed. Self sterilizing activity of TiO 2 films toward different microorganisms was studied in many works [9][10][11][12][13][14].…”

Uso de fotocatálise eletroassistida com diferentes fontes de radiação e material nanoestruturado para tratamento de um fármaco em água

“…A lâmpada de luz negra apresenta diversas aplicações, ela tem sido utilizada na oxidação fotocatalítica de compostos orgânicos tóxicos do ar, degradação de compostos farmacêuticos, como também na desinfecção de águas para a inativação de microorganismos a partir da fotocatálise (JEONG et al, 2004;RENGIFO-HERRERA et al, 2010;VAIANO et al, 2015).…”

“…Decorrente do seu comprimento de onda na região de 320 -400 nm (UV-A), a lâmpada de luz negra acaba sendo extensamente utilizada como uma fonte de radiação, já que suas emissões são ideias para a excitação do TiO 2 , promovendo os elétrons da BV para a BC (RENGIFO-HERRERA et al, 2010). Também é bastante utilizada, por ser uma lâmpada que produz pouco aquecimento da solução irradiada.…”