Titania nano-coated quartz wool for the photocatalytic mineralisation of emerging organic contaminants.

ABSTRACT

Many emerging contaminants pass through conventional wastewater treatment plants, contaminating surface and drinking water. The implementation of advanced oxidation processes in existing plants for emerging contaminant remediation is one of the challenges for the enhancement of water quality in the industrialised countries. This paper reports on the production of a TiO2 nano-layer on quartz wool in a relevant amount, its characterisation by X-ray diffraction and scanning electron microscopy, and its use as a photocatalyst under ultraviolet radiation for the simultaneous mineralisation of five emerging organic contaminants (benzophenone-3, benzophenone-4, carbamazepine, diclofenac, and triton X-100) dissolved in deionised water and tap water. This treatment was compared with direct ultraviolet photolysis and with photocatalytic degradation on commercial TiO2 micropearls. The disappearance of every pollutant was measured by high performance liquid chromatography and mineralisation was assessed by the determination of total organic carbon. After 4 hours of treatment with the TiO2 nano-coated quartz wool, the mineralisation exceeds 90% in deionised water and is about 70% in tap water. This catalyst was reused for seven cycles without significant efficiency loss.