Visible Light–Driven Advanced Oxidation Processes to Remove Emerging Contaminants from Water and Wastewater: a Review

Abstract

The scientific data review shows that advanced oxidation processes based on the hydroxyl or sulfate radicals are of great interest among the currently conventional water and wastewater treatment methods. Different advanced treatment processes such as photocatalysis, Fenton’s reagent, ozonation, and persulfate-based processes were investigated to degrade contaminants of emerging concern (CECs) such as pesticides, personal care products, pharmaceuticals, disinfectants, dyes, and estrogenic substances. This article presents a general overview of visible light–driven advanced oxidation processes for the removal of chlorfenvinphos (organophosphorus insecticide), methylene blue (azo dye), and diclofenac (non-steroidal anti-inflammatory drug). The following visible light–driven treatment methods were reviewed: photocatalysis, sulfate radical oxidation, and photoelectrocatalysis. Visible light, among other sources of energy, is a renewable energy source and an excellent substitute for ultraviolet radiation used in advanced oxidation processes. It creates a high application potential for solar-assisted advanced oxidation processes in water and wastewater technology. Despite numerous publications of advanced oxidation processes (AOPs), more extensive research is needed to investigate the mechanisms of contaminant degradation in the presence of visible light. Therefore, this paper provides an important source of information on the degradation mechanism of emerging contaminants. An important aspect in the work is the analysis of process parameters affecting the degradation process. The initial concentration of CECs, pH, reaction time, and catalyst dosage are discussed and analyzed. Based on a comprehensive survey of previous studies, opportunities for applications of AOPs are presented, highlighting the need for further efforts to address dominant barriers to knowledge acquisition.

Removal of insecticides from waters and soils by sulfate radical‐based advanced oxidation processes

“…Activated persulfate and peroxymonosulfate-based advanced oxidation processes (AOPs) for antibiotics degradation [29] Removal of pharmaceutical micropollutants from real wastewater matrices by means of photochemical advanced oxidation processes-a review [30] APPLIED RESEARCH | 3 of 27 [14], the treatment of insecticide solutions by means of Fenton-based processes was detailed exposing some comparative studies with activated PS. Matafonova and Batoev [25] and Zawadzki [26] described the general behavior of the removal of pollutants by UV and visible light treatments, respectively, whereas the overview of Vagi and Petsas [2] considered the remediation of waters with organochlorine and organophosphorus pesticides by AOPs up to 2018 (see effluents, but also in many soils to verify their possible suitability to be applied at industrial level.…”

“…Recent advances in the application of UV light-emitting diodes for degrading organic pollutants in water through advanced oxidation processes: a review [25] Visible light-driven advanced oxidation processes to remove emerging contaminants from water and wastewater: a review [26] Pharmaceuticals Remediation of antibiotic wastewater by coupled photocatalytic and persulfate oxidation system: a critical review.…”

“…In our previous review [14], the treatment of insecticide solutions by means of Fenton‐based processes was detailed exposing some comparative studies with activated PS. Matafonova and Batoev [25] and Zawadzki [26] described the general behavior of the removal of pollutants by UV and visible light treatments, respectively, whereas the overview of Vagi and Petsas [2] considered the remediation of waters with organochlorine and organophosphorus pesticides by AOPs up to 2018 (see Table 1).…”

“…Both radicals are able to destroy most organics up to finally achieve their overall mineralization with their transformation into CO 2 , water, and inorganic ions (Cl − , SO An example is the well-known Cl − oxidation to form active chlorine (Cl 2 /HClO/ClO − ) that can produce chloroderivatives even more recalcitrant than the parent organic molecules [15][16][17]. Table 1 lists selected reviews reporting the removal of different organic pollutants by sulfate radical based-AOPs [2,[21][22][23][24][25][26][27][28][29][30], demonstrating the great interest of these technologies for water treatment. As can be seen, any previous review has summarized all the PS-and PMS-based AOPs applied to destroy insecticides from waters and soils, collecting all the developing time of these oxidation technologies that is upgraded since 2018.…”

Physicochemical Properties of Tungsten Trioxide Photoanodes Fabricated by Wet Coating of Soluble, Particulate, and Mixed Precursors

“…The conductivity of urban and industrial wastewater is adequate due to the presence of electrolytes [13]. The majority of PEC research has typically utilized synthetic wastewater composed of ultrapure water and electrolytes [12,[14][15][16][17]. The process-specific parameters, system design, and water quality all play a role in determining the formation of radicals [4,18,19].…”