Ozonation of carbamazepine, diclofenac, sulfamethoxazole and trimethoprim and formation of major oxidation products

Abstract

The degradation of four pharmaceuticals, carbamazepine (CBZ), diclofenac (DCF), sulfamethoxazole (SMX) and trimethoprim (TMP) by ozonation was studied under a range of experimental conditions, including ozone dosage and concentration of target compounds. The concentration profile of the pharmaceuticals and detection of any by-products formed was carried out using liquid chromatography mass spectrometry. CBZ, DCF, TMP and SMX at initial concentration of 5 mg/L each were degraded to below the method detection limit (1 μg/L) when they reacted with 1.6, 2.3, 2.8 and 4.5 mg/L of ozone, respectively. For each parent compound several by-products were detected after the ozone treatment. A number of these by-products have not been previously reported in the literature. Some of these by-products were founds to be quite resistant to ozone up to applied ozone dosages of 15 mg/L.

Keywords:

• Ozonation
• By-product identification
• Pharmaceuticals
• Wastewater treatment

Acknowledgement

PhD Scholarship support from Taibah University, Saudi Arabia, to Sultan Alharbi is gratefully acknowledged.

Notes

Presented at the 8th International Conference on Challenges in Environmental Science & Engineering (CESE-2015) 28 September–2 October 2015, Sydney, Australia