This review is devoted to oxidative water treatments, with emphasis on catalytic ozonation. The approach tackled herein resides in exposing a wide variety of oxidative treatments attempts as a basis for summarizing the main findings that allow envisaging improvements aiming towards total mineralization of organic pollutants. Comparison between specific operating conditions for specific pollutant-catalyst-oxidizing systems is quite difficult, and is not targeted in the present work. However, when deeply and judiciously analyzed, such a comparison allows demonstrating that, except for some works, most of these attempts seldom took into accounts basic requirements such as the parameter interactions, the role of cation mobility around a solid surface, if any, the multiple pollutant-catalyst-oxidizing species interactions and the significant contribution of adsorption, etc. Otherwise, how to explain that many experiments are still conducted with unsuitable catalysts under totally inadequate operating conditions? A better understanding of the essential requirements for a catalyst to achieve total mineralization of any organic molecules is the main objective of this work. The data summarized herein allow devoting a special interest to ozone, which is a powerful oxidizing agent and probably the most easily handleable, in spite of its low solubility in water. The use of catalysts is an ultimate strategy to improve the ozonation performance, by reducing the chemical oxygen demand (COD), even until total disappearance. However, solid catalysts, more particularly those developing high specific surface areas, such as silicates, aluminosilicates, zeolites, pseudozeolites, and clay minerals and derivatives are expected to display appreciable performances in ozonation. The latest findings show strong dependency of their catalytic activity on the chemical and physical characteristics of their surface, their concentration in the liquid media, the pH level of the reaction mixture and other parameters. The effects of these factors will be systematically examined in this review paper. The state-of-the-art in the catalytic ozonation of organic pollutants may be useful to understand the contribution of both surface and bulk ozonation reaction in the vicinity of the surface of a solid catalyst, and more particularly the role of the catalytic agent and its mobility near the solid surface. A rigorous data synthesis, made available in the present paper, allows understanding the ozone scavenging by the very species present in water, and correlating the highest effectiveness of ozone in the presence of optimum catalyst concentration at optimum pH. This supposes strong interactions between the main factors, which remain to be elucidated for each type of catalyst. The structure of this review makes emphasis on montmorillonite, which exhibits most of the required properties for effective ozonation catalysts. These are common features of natural clay minerals and zeolites, which appear as interesting candidates for large-scale water treatments, targeting complete mineralization of organic pollutants without generating persistent toxins.

Advances in catalytic oxidation of organic pollutants - Prospects for thorough mineralization by natural clay catalysts

Post-endogenous denitrification and phosphorus removal in an alternating anaerobic/oxic/anoxic (AOA) system treating low carbon/nitrogen (C/N) domestic wastewater

Organic substrate transformation and sludge characteristics in the integrated anaerobic anoxic oxic–biological contact oxidation (A2/O–BCO) system treating wastewater with low carbon/nitrogen ratio

Increasing economic and environmental benefits of media-based aquaponics through optimizing aeration pattern

Two of the activated sludge models within STOAT, a whole plant modeling program developed at the Water Research Centre, were compared and shown to have definite differences in predictions (Stokes et al, 2000a) The International Water Association, IWA, (formerly IAWQ) Activated Sludge Model No 1 (ASM1) within STOAT was shown to provide better predictions over a wider range of process conditions and for optimizing nitrification/denitrification than the biochemical oxygen demand (BOD) based ASAL model The sludge yield predictions were also different for the two models (Stokes et a/, 2000b), and the authors suggested that predicted values in ASAL were influenced by the mixing regime selected for the aeration tank

https://onlinelibrary.wiley.com/doi/pdf/10.2175/106143010X12756668800898

Activated sludge and other aerobic suspended culture processes.

Optimizing aeration rate in an external nitrification–denitrifying phosphorus removal (ENDPR) system for domestic wastewater treatment

Pilot-scale demonstration of a novel process integrating Partial Nitritation with simultaneous Anammox, Denitrification and Sludge Fermentation (PN + ADSF) for nitrogen removal and sludge reduction.

The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron: Resistance difference and mechanisms

The level of microplastics (MPs) in wastewater treatment plants (WWTPs) has been well evaluated by the particle number, while the mass concentration of MPs and especially nanoplastics (NPs) remains unclear. In this study, pyrolysis gas chromatography–mass spectrometry was used to determine the mass concentrations of MPs and NPs with different size ranges (0.01–1, 1–50, and 50–1000 μm) across the whole treatment schemes in two WWTPs. The mass concentrations of total MPs and NPs decreased from 26.23 and 11.28 μg/L in the influent to 1.75 and 0.71 μg/L in the effluent, with removal rates of 93.3 and 93.7% in plants A and B, respectively. The proportions of NPs (0.01–1 μm) were 12.0–17.9 and 5.6–19.5% in plants A and B, respectively, and the removal efficiency of NPs was lower than that of MPs (>1 μm). Based on annual wastewater effluent discharge, it is estimated that about 0.321 and 0.052 tons of MPs and NPs were released into the river each year. Overall, this study investigated the mass concentration of MPs and NPs with a wide size range of 0.01–1000 μm in wastewater, which provided valuable information regarding the pollution level and distribution characteristics of MPs, especially NPs, in WWTPs.

https://pubs.acs.org/doi/pdf/10.1021/acs.est.2c07810

Assessing the Mass Concentration of Microplastics and Nanoplastics in Wastewater Treatment Plants by Pyrolysis Gas Chromatography–Mass Spectrometry

Legacy and emerging poly- and perfluoroalkyl substances in wastewater treatment plant and receiving water: abundance, removal, and potential ecological risk

Feng Hou

Papers

Optimizing aeration rate in an external nitrification–denitrifying phosphorus removal (ENDPR) system for domestic wastewater treatment

Pilot-scale demonstration of a novel process integrating Partial Nitritation with simultaneous Anammox, Denitrification and Sludge Fermentation (PN + ADSF) for nitrogen removal and sludge reduction.

The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron: Resistance difference and mechanisms

Assessing the Mass Concentration of Microplastics and Nanoplastics in Wastewater Treatment Plants by Pyrolysis Gas Chromatography–Mass Spectrometry

Legacy and emerging poly- and perfluoroalkyl substances in wastewater treatment plant and receiving water: abundance, removal, and potential ecological risk

Feng Hou

Papers

Optimizing aeration rate in an external nitrification–denitrifying phosphorus removal (ENDPR) system for domestic wastewater treatment

Pilot-scale demonstration of a novel process integrating Partial Nitritation with simultaneous Anammox, Denitrification and Sludge Fermentation (PN + ADSF) for nitrogen removal and sludge reduction.

The inactivation of bacteriophages MS2 and PhiX174 by nanoscale zero-valent iron: Resistance difference and mechanisms

Assessing the Mass Concentration of Microplastics and Nanoplastics in Wastewater Treatment Plants by Pyrolysis Gas Chromatography–Mass Spectrometry

Legacy and emerging poly- and perfluoroalkyl substances in wastewater treatment plant and receiving water: abundance, removal, and potential ecological risk

Pilot-scale demonstration of a novel process integrating Partial Nitritation with simultaneous Anammox, Denitrification and Sludge Fermentation (PN + ADSF) for nitrogen removal and sludge reduction.