Removal of selected pharmaceuticals from tap water by the Fenton process

ABSTRACT

In recent years, there has been an increasing interest in removal of emerging contaminants in natural waters due to persistence in the aquatic ecosystem. Conventional water treatment processes are generally insufficient for the removal of these contaminants. Depending on this, advanced oxidation processes (AOPs) may be considered as an alternative to this problem. In this study, Fenton process which produces hydroxyl radicals by the reaction between iron salts and hydrogen peroxide was investigated for the removal of some pharmaceutical residues from tap water. The tap water spiked Carbamazepine (CBZ), Caffeine (CAF) and Paracetamol (PRC) with particular concentrations.All initial and final pharmaceutical concentrations were measured separately by LC-MS/MS to calculate percent removal efficiencies accurately. The optimum concentrations are 0.6 mg/L H₂O₂ − 8 mg/L Fe²⁺ and 7.5 mg/L H₂O₂-6 mg/L Fe²⁺ for CBZ and CAF, respectively. CBZ and CAF removal efficiency have been detected 99.77% and 99.66%. Solutions obtained after CAF removal were re-measured in LC-MS/MS for 1,7 dimethylxanthine. But 1,7 dimethylxanthine (paraxanthine) which was studied as a by-product of CAF could not be determined on measurements. 99.11% removal efficiency was obtained for PAR at 5 mg/L H₂O₂ and 10 mg/L Fe²⁺ concentration. Increased H₂O₂ and Fe²⁺ concentration affect the yield of Fenton oxidation in all pharmaceutical residues.

KEYWORDS:

• Fenton
• oxidation
• pharmaceuticals
• tap water
• treatment

Acknowledgments

This work was supported by Aksaray University Scientific Research Projects Coordination Unit. Project number: 2013-016.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors thank Aksaray University Scientific Research Projects Coordination Unit for their financial support [Project number: BAP2013-016].