Degradation of wine industry wastewaters by photocatalytic advanced oxidation

Abstract

Wine industry wastewaters contain a high concentration of organic biodegradable compounds as well as a great amount of suspended solids. These waters are difficult to treat by conventional biological processes because they are seasonal and a great flow variation exists. Photocatalytic advanced oxidation is a promising technology for waters containing high amounts of organic matter. In this study we firstly investigated the application of H2O2 as oxidant combined with light (artificial or natural) in order to reduce the organic matter in samples from wine industry effluents. Secondly, we studied its combination with heterogeneous catalysts: titanium dioxide and clays containing iron minerals. The addition of photocatalysts to the system reduces the required H2O2 concentration. Although the H2O2/TiO2 system produces higher efficiencies, the H2O2/clays system requires a H2O2 dosage between three and six times lower.

Solar photo-Fenton treatment of winery effluents in a pilot photocatalytic reactor

“…So far, there are numerous studies dealing with treatment of winery effluents with photocatalysis, however, only one study has assessed the treatability of actual wastewater [30], whereas the majority has used simulated winery effluents by diluting wine or grape juice with deionized water [31][32][33][34].…”

Photocatalytic decolorization of methylene blue dye by Ag3PO4–AgX (X = Cl−, Br− and I−) under visible light

“…Photocatalytic reaction is one of the advance oxidation processes that the reactive species such as hydroxyl radical ( Å OH) or superoxide anion radical ð Å O À 2 Þ can be generated after the photocatalyst absorbs the photons which has energy greater than or equal to its band gap energy, in aqueous environment [1][2][3]. These reactive species are the powerful oxidizers that degrade organic molecules including dyes.…”

Synergistic Water-Treatment Reactors Using a TiO2-Modified Ti-Mesh Filter

“…It is known that these factors ultimately decrease the photocatalytic efficiency of water treatment [3,51,52]. On the other hand, adding ozone to the water purification system results in an overall improvement in water quality due to more complete oxidation of color, organics, and suspended solids [53,54]. At the same time, ozone-induced microflocculation can reduce SS [55].…”