Iprodione Removal by UV-Light-, Zero-Valent Iron- and Zero-Valent Aluminium-Activated Persulfate Oxidation Processes in Pure Water and Simulated Tertiary Treated Urban Wastewater

Abstract

The degradation of iprodione (IPR), a once frequently used but recently banned dicarboximide fungicide, by UV-C light-, zero-valent iron- (ZVI), and zero-valent aluminium (ZVA)-activated persulfate (PS) oxidation processes was comparatively studied in distilled (pure) water (DW) and simulated, tertiary treated urban wastewater (SWW). The performance of PS-activated oxidation processes was examined by following IPR (2–10 mg/L) removal, PS (0.01–1.00 mM) consumption, metal ion release (for the two heterogeneous catalytic oxidation processes), dissolved organic carbon (DOC) removal as well as hydroxylated aromatic and low molecular weight aliphatic degradation products. The effect of pH and PS concentrations on IPR removal was examined in DW. While the experiments in DW highlighted the superior performance of UV-C/PS treatment (with 78% DOC removal after 120 min at pH = 6.2), the performance of UV-C/PS treatment decreased sharply (to 24% DOC removal after 120 min at pH = 6.8) in the complex wastewater matrix (in SWW). Complete IPR (in 20 min) and 40% DOC (in 120 min) removals were obtained with ZVI/PS treatment (1 g/L ZVI, 1.5 mM PS, pH = 3.0), which was the most effective oxidation process in SWW. The treatment performance was strongly influenced by the SWW constituents, and UV-C/PS treatment appeared to be the most sensitive to it.

Life Cycle Assessment as a Decision-Making Tool for Photochemical Treatment of Iprodione Fungicide from Wastewater

“…All chemicals and reagents used in this study were purchased from Sigma-Aldrich ® (Merck, Istanbul, Turkey) and were of analytical grade. The composition of the TWW sample was composed of different organic and inorganic components: (NH 4 ) 2 SO 4 (12 mg/L), tryptone (50 mg/L), meat extract (50 mg/L), yeast extract (7.5 mg/L), urea (7.5 48 mg/L), K 2 HPO 4 (10 mg/L), CaCl 2 .2H 2 O (1 mg/L), and MgSO 4 .7H 2 O (1 mg/L) [20]. In addition to the above-mentioned chemicals, 4 mg/L of humic acid was also added to the reaction solution as an organic compound, which rendered the TWW composition more complex and typical for urban effluent.…”

“…In addition to the above-mentioned chemicals, 4 mg/L of humic acid was also added to the reaction solution as an organic compound, which rendered the TWW composition more complex and typical for urban effluent. Urban wastewater generally contains a mixture of industrial wastewater, domestic wastewater, and run-off rainwater [20]. The pH of the TWW was around 6.4-6.8, and it was 5-fold diluted with distilled water (DW) to obtain a final DOC content of 10 mg/L, which is a typical DOC for tertiary treated effluent TWW.…”

“…More recently, iprodione was also used to kill nematodes and filed for patent protection for that purpose [17]. Although its approval in the EU market was not renewed in 2017 [18] and the product was banned later in 2019 [19], since there was no alternative or replacement product recommended for this fungicide, its use in agricultural activities continued for a while in some countries, such as Turkey, that had used the fungicide intensively [20].…”

“…In these few studies, dechlorination has been reported as a primary stage of iprodione degradation, followed by hydroxyl group replacement [27,28]. Only a few papers have reported the removal of iprodione using UV-C light and its combination with hydrogen peroxide from an aqueous solution [20,[27][28][29][30]. Moreover, there is no study available in the scientific literature dealing with the environmental impacts of these rather energy-intensive, chemical-consuming treatment processes.…”

New Perspectives in Photocatalytic Water Treatment

“…Removal of emerging pollutants from natural waters as well as from treated wastewaters holds prime importance. In this respect, a comparative study was presented by Montazeri and colleagues [6]. Applied AOPs were UV-light-, zero-valent iron-(ZVI) and zero-valent aluminum(ZVA)-activated persulfate (PS) oxidation processes.…”