NF/RO removal of enrofloxacin and its photodegradation products from water

Abstract

Once released into the environment pharmaceuticals undergo a series of processes leading to their degradation. Photolysis induced by sunlight is the most important way of pharmaceuticals degradation in water. In this work the removal of enrofloxacin (ENRO) and its photodegradation products with nanofiltration (NF) and reverse osmosis (RO) membranes was investigated. ENRO solution (10 mg L⁻¹, pH = 8) was irradiated under artificial light for 2 h. As a result the degradation of ENRO produced three photoproducts with molecular weights (MW) 389, 373 and 114 g mol⁻¹. Reverse osmosis (LFC–1, SWC4+) and tight nanofiltration (NF90) membranes almost removed (>99.99%) all the compounds (parent and photodegradation products), but the other nanofiltration (DK, NF and HL) membranes removed more than 92%, with one exception (36.96% for the compound with MW 114 g mol⁻¹) obtained using HL membrane.

Keywords:

• Enrofloxacin
• Photolysis
• Photodegradation products
• Reverse osmosis
• Nanofiltration

Acknowledgements

This work was supported by the Croatian Ministry of Science, Education and Sports Projects: 125-1253008-3009 “Membrane and adsorption processes for removal of organic compounds in water treatment,” and 125-1253008-1350 “Advanced analytical methods for pharmaceuticals determination in the environment.”

Notes

Presented at the International Conference on Desalination for the Environment, Clean Water and Energy, European Desalination Society, 23–26 April 2012, Barcelona, Spain

aEffective diameter of organic compound in water [30].