2. ENVIRONMENTAL ChEMISTRy & TEChNOLOGy 2.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Environmental Chemistry & Technology
rates for partial oxidation and mineralization. Benzothiazole
was identified as the first ozonation product, reaching up to
60 mol% of the original MBT concentration, followed by low
concentration of 2(3-H) benzothiazolone.
The results of absorption of ozone in the fresh water
and in the synthetic wastewater containing MBT are given in
Fig. 2. The saturation concentration of ozone 23.1 mg dm –3
was achieved in fresh water after 35 minutes. Specific ozone
consumption values were 0.78 g g –1 for COD and 1.88 g g –1
for TOC.
Fig. 1. COD, TOC and MbT as a function of ozonation time at
oxygen flow rate 30 dm 3 h –1 and W = 70 %
Conclusions
Respirometric tests confirmed that this compound is not
biodegradable. Activated sludge showed adsorption affinity
to MBT at concentration values up to 60 mg dm –3 . Significant
decrease of MBT content was observed after five minutes
of ozonation. Correspondent efficiency values for COD
and TOC removal were 55 and 16 %. COD removal rate
5.2 mg dm –3 min –1 was observed at 70 % of maximum ozone
s337
Fig. 2. utilization of ozone in demineralised water and in synthetic
wastewater contentaining MbT
generator power. The presence of benzothiazole was identified
as ozonation intermediate. It can be concluded that MBT
is readily transformed by ozonation.
This work has been supported by the Slovak Grant
Agency for chemical and chemical-technological science
(Grant No 1/0866/08).
REFEREnCES
1. De Wever H., Verachtert H.: Water Research 31, 2673
(1997).
2. Chudoba J., Tuček F., Zeis K:. Acta Hydrochim. Hydrobiolo.
5, 495 (1977).
3. Whittaker M. H., Gebhart A. M., Miller T. C., Hammer
F.: Toxicol And Health. 2004, 49.
4. Reemtsma T., Fiehn O., Kalnowski G. and Jekel M.:
Environ. Scien. Technol. 29, 478 (1995).
5. Fiehn O., Wegener G., Jochimsen J. and Jekel M.: Water
Research 32, 1075 (1998).