ENVR 149 |
| Many wastewaters are constituted by compounds of different nature with phenols as one of the main groups. In particular, wastewater generated during some food and liquor processes (olive oil, table olives, wine distilleries, etc.) contain polyphenols that constitute the main polluting problems of these industries. In this work, a polyphenol mixture in water has been prepared from three main polyphenols present in the wastewaters indicated above: gallic acid, syringic acid and tyrosol. In the ozonation of individual polyphenols, regarding the evolution of TOC, gallic acid ozonation reaches about 80% TOC removal (without activated carbon) and nearly complete mineralization (with activated carbon) after three hours of treatment. The second most reactive process is the ozonation of tyrosol that after three hours of treatment allows nearly 50% mineralization (without activated carbon) and, as in the case of gallic acid, nearly complete removal of TOC in the presence of activated carbon. Syringic acid ozonation seems to be the most refractory process with mineralization of 57% and 12% with and without activated carbon, respectively. In polyphenol wastewater ozonation, the order of reactivity with ozone of the polyphenols studied was similar to that observed for the case of individual ozonations: gallic acid > syringic acid > tyrosol. Again, if TOC is considered, the presence of activated carbon results in significant decreases of this parameter. Thus, after 180 minutes, 52 and 88% removals are achieved in the absence and presence of activated carbon, respectively. In all the cases, during the first two hours of treatment ozone consumption to remove TOC is always lower in the ozone-activated carbon process than in the activated carbon-free ozonation process. The results, then, suggest the suitability of the process for real polyphenol wastewaters. |
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General Papers
6:00 PM-8:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Environmental Chemistry |