A laboratory study was conducted to investigate the kinetics and byproducts of simazine oxidation by ozone, ultraviolet radiation (UV), and combined ozone and UV. Byproducts were identified by HPLC. Simazine was oxidized rapidly by ozone, UV, and ozone and UV. For example, 4 mg/L simazine disappeared completely after oxidation by 34 mg/min ozone at pH 7.2 for 15 minutes. Simazine disappearance rates during ozonation increased with applied ozone dose and pH. Dealkylation and dechlorination byproducts were formed, and deamination byproducts appeared at higher ozone doses or higher pH. During UV and ozone and UV oxidation, simazine disappearance rates increased with UV intensity. Dechlorination byproducts were formed by UV oxidation. Dealkylation, deamination, and dechlorination byproducts were formed by combined ozone and UV treatment. In comparing oxidation systems, simazine disappearance rates during ozonation at pH 9.9 were similar to those observed during ozone and UV oxidation. Water Environ. Res., 67, 340 (1995).

ABSTRACf:Batch biodegradation studies were conducted to assess the biodegradability of single s-triazines. s-Triazines tested included simazine, a widely used herbicide, and its products resulting from oxidation with ozone, ultraviolet (UV) light, and combined ozone and UV light oxidation. Degradation rates for each s-triazine were calculated as IL M N/hr. Rates ranged from 0 to 10.3 ILM N/hr. s-Triazine degradation rates were a function of the ring substituents and followed the order of hydroxỹ amino~chlorine 20 ethylamino. Chemical oxidation methods capable of oxidizing the more persistent simazine substituent groups (chlorine and ethylamine) to more easily biodegraded substituents (amine and hydroxy) proved attractive in enhancing the s-triazine mineralization of simazine. When simazine was pretreated with combined ozone and UV, the s-triazine biodegradation rate was increased by an order of magnitude. s-Triazine biodegradation rates also were enhanced with ozone and UV pretreatment but not to the same extent. W a te r E n v ir o n . R e s .. 67, 347 (1995).

A s a result of manufacturing operations at the Durez Division of Occidental Chemical Corporation (OCC) located in North Tonawanda

As a result of manufacturing operations at the Durez Division of Occidental Chemical Corporation (OCC) located in North Tonawanda, New York, a highly phenolic wastestream is produced. At the time of this study, average phenols and total COD concentrations of the wastestream averaged 35,000 and 10,000 mg/L. Studies were conducted at the Durez Facility to assess sequenced anaerobic/aerobic biological activated carbon (BAC) process treatment of this wastestream. The first stage anaerobic BAC process achieved significant organic conversion with minimal solids production, and near stoichiometric methane production. Excellent polishing of the AnBAC process effluent was achieved in the aerobic BAC unit even under variable influent conditions. Effluent filterable COD from the aerobic BAC process averaged 165 mg/L and was speculated to be primarily non‐biodegradable soluble metabolic endproducts. Effluent phenols from the process typically were below 0.01 mg/L and averaged 0.04 mg/L. Overall process efficiency for total COD, filterable COD, and phenols were > 97, > 99, and approximately 100 percent, respectively.