The intriguing role of the aqueous matrix in advanced water disinfection: can a harmonic relationship be achieved?

Abstract

AbstractThis perspective article primarily discusses the role of water matrix for the advanced treatment of watercourses. This relies on experimental work regarding the inactivation of Escherichia coli, Enterococcus faecalis, and Vibrio parahaemolyticus by an advanced oxidation process, namely activated persulfate, in five matrices of varying complexity, (i.e., from as simple as deionized water to secondary treated effluent). For comparison purposes, respective tests were performed with ultraviolet (UVC) radiation, a conventional disinfection process, while results from recent literature are also discussed. Only in deionized water can activated persulfate (i.e., 150 mg L−1 sodium persulfate and 30 mg L−1 ferrous ions) completely inactivate all three bacteria in the course of several minutes, but the process is ineffective in other matrices (i.e., bottled, tap, or lake water, as well as wastewater), where 1–2 orders of magnitude longer times are needed for partial inactivation, which decreases in the order E. coli > E. faecalis ~ V. parahaemolyticus. Conversely, UVC (at 30 W nominal value) is highly efficient against all bacteria and in all matrices in a matter of just a few seconds. The general perception is that treatment efficiency decreases with increasing matrix complexity in terms of total concentration and/or individual components composition, irrespective of the applied treatment method and its objectives (i.e., disinfection, decontamination, or mineralization). However, there are always exceptions the rule, further highlighting how case‐specific advanced water treatment can be. The matrix itself should be given particular emphasis for the rational design of efficient water treatment processes. © 2023 Society of Chemical Industry (SCI).