Use of Ultra-Violet assisted Titanium Dioxide photocatalysis for the removal of di (2-ethylhexyl) phthalate from industrial wastewaters

Abstract

Urbanization of many cities with industrial, commercial, and residential areas in the world takes place at an unprecedented scale. Di (2-ethylhexyl) Phthalate (DEHP) is a commonly used plasticizer in number of industries and becomes a precursor to cause DEHP contamination of watercourses through untreated or partially treated industrial wastewater effluents. Such contamination by DEHP may result in bioaccumulation and bio-concentration in biota so that it will adversely affect humans through food chain. Titanium dioxide (TiO2) nanoparticles were experimented to remove DEHP through photocatalysis. The photocatalysis with TiO2 for the destruction of DEHP was found to be a promising technique in removing DEHP from industrial wastewaters. The most economical dosage of TiO2 would be one gram and it needs to be photocatalysed for a period of approximately 45 minutes for complying with the permissible level stipulated for DEHP (16 μg/L) for the protection of aquatic life. The cost of the photocatalysis with TiO2 was around Rs. 120 and the cost could be further reduced when the material (TiO2) is regenerated for subsequent usage. TiO2 was regenerated for three times with inherent properties for photocatalysis being not changed. This technique could be successfully applied to lessen the DEHP levels in the urban watercourses of Sri Lanka.