Emergent chemical in sewage treatment plant: di-(2-ethylhexyl) phthalate

Abstract

In this work a simple gravimetric method was described for the study of di-(2-ethylhexyl) phthalate (DEHP) in wastewater samples from the inflow and outflow points of the sewage treatment plant (ETE) at the University of Caxias do Sul (UCS). The organic phase of the sample was precipitated by adding concentrated HCl. The precipitate was filtered in glass columns packed with treated cotton. After drying, the columns containing the precipitate were carefully weighted and extracted with n-hexane. After solvent evaporation, the organic extract was re-diluted and analyzed by Gas Chromatography with Flame Ionization Detection (GC/FID). The average rate of DEHP removal was 27.50%. The median DEHP concentration was 6.01 µg mL -1 at the outflow point. This DEHP concentration is well above the maximum concentration level reported in the literature.