OXIDATION OF REFRACTORY ORGANIC MATERIALS BY OZONE AND ULTRAVIOLET LIGHT

摘要

An. experimental study of an advanced chemical oxidation system: Ozone Combined with UV Radiation, was carried out to determine the rates of oxidation of difficult to oxidize, "refractory", chemical species which are not removed by conventional secondary treatment plus carbon absorption. One representative was chosen for this investigation from each of the five types of refractories in municipal wastewater, alcohol, acid, amino acid, fatty acid, and polyhydroxyl alcohol. The results indicate that the subject species are not oxidized by the strong oxidant ozone alone, but are readily oxidized by ozone when reaction is activated by UV radiation, with enhancement of 100 to 1000 fold. A refractory index scale was established to provide a means of comparing the resistance to oxidation of refractory compounds, and it gives values from < to > 1000 for KCN on the low end, to acetic acid on the high end. One of the most difficult of all organic species to oxidize is acetic acid (> 1000 on the Refractory Index Scale) but it is readily oxidized by 03 with UV. All of the refractories investigated benefited by at least an order of magnitude increase in reaction rate when UV and ozone are used over that obtained when ozone alone is used. The use of moderate amounts of UV is felt to be more effective than substantial elevations in temperature.