Promotion of photo-induced based green technologies for water treatment with pesticides content, FENPEST

Abstract

Developmant of a technology for advanced degradation of pesticides (maximum admitted concentrations <0.1 μg/L) from water applying an advanced photocatalytic oxidation process, using sunlight as UVVIS irradiance source, associated with iron based catalyst separation by flotation and its valorization in the degradation process. Project results were concretized by the followings: -Establishment of database regarding the mechanisms, kinetics, performance of Fenton, photo-Fenton advanced oxidation processes on pesticides degradation and the flotation process applied for catalyst recovery; -Definition of contaminated sites with various classes of pesticides by identifying their concentration domains and associated pollution matrices of different water sources; Unitary flow developed for the treatment of water containing Lindane by advanced oxidation – flotation process includes: –Wastewater treatment line with the following sequence of operations: pretreatment by settling, UV-VIS/H2O2/Fe2+ advanced oxidation- Fe3 +precipitation- flotation; – Line of Fe3 +recovery (as FeSO4) applying the following operations: centrifugation-acid solubilisation. The product obtained can be capitalized as photocatalysts in the advanced oxidation treatment phase or as coagulant for other water treatment processes. For each proposed stages / operations the operating parameters and the consumptions of reagents were set in order to assures advanced degradation of Lindane from wastewater (tens μg/L) and Fe3+separation, with the compliance of treated effluent quality with the limits for discharging into surface waters (Lindane ≤ 0.02 μg/L, ΣHCH ≤ 0.042 μg/L, Fe <2 mg/L)