Publications de Urs von Gunten

Characterization of Organic Nitrogen by Chlorination, Ozonation, and Stable Isotope Analysis of Nitrate

During oxidation, nitrogenous species in dissolved organic matter (DOM) are critical in the formation of nitrogenous, potentially toxic disinfection byproducts, but their chemical identity remains poorly understood. Here, we developed three complementary a ...

American Chemical Society (ACS)2025

Enhanced abatement of phenolic compounds by chlorine in the presence of CuO: Absence of electrophilic aromatic substitution

Urs von Gunten

It has been demonstrated that chlorine predominately reacts with phenolic compounds through an electrophilic aromatic substitution, yielding chlorinated phenols. Previous studies showed that copper oxide (CuO), a water pipe corrosion product, can catalytic ...

PERGAMON-ELSEVIER SCIENCE LTD2025

Effect of surfactants on inactivation of Bacillus subtilis spores by chlorine

Urs von Gunten, Sandor Kasas, María Inés Villalba, Tianqi Zhang

Bacterial spores pose significant risks to human health, yet the inactivation of spores is challenging due to their unique structures and chemical compositions. This study investigated the synergistic effect between surfactants and chlorine on the inactiva ...

2025

Ozonation of wastewater effluent by the MEMBRO3X contactor: Micropollutants abatement and bromate mitigation

Urs von Gunten, Jaedon Shin

Wastewater treatment plants (WWTPs) are significant sources of micropollutants, potentially adversely affecting freshwater ecosystems. Ozonation is an effective way to abate micropollutants during treatment of wastewater effluent, however, the presence of ...

2025

Reactions of N,O- and N,S-Azoles and -Azolines with Ozone: Kinetics and Mechanisms

Urs von Gunten

N,O- and N,S-azoles and -azolines are common functional groups in pharmaceuticals, agrochemicals and natural products. Their fate during ozone-based water treatment processes is unknown due to a lack of kinetic and mechanistic information on their reaction ...

American Chemical Society (ACS)2025

Unveiling the reaction chemistry of sulfoxides during water chlorination

Urs von Gunten

Species-specific second-order rate constants for the reactions of eight model sulfoxides with hypochlorous acid (k(HOCl)) were determined to be in the range of 2.7 M-1 s(-1) to 5.8 x 10(3) M-1 s(-1). A quantitative structure-activity relationships (QSAR) w ...

PERGAMON-ELSEVIER SCIENCE LTD2025

Reactions of hypobromous acid with dimethyl selenide, dimethyl diselenide and other organic selenium compounds: kinetics and product formation

Urs von Gunten

Selenium (Se) is an essential micronutrient for many living organisms particularly due to its unique redox properties. We recently found that the sulfur (S) analog for dimethyl selenide (DMSe), i.e. dimethyl sulfide (DMS), reacts fast with the marine oxida ...

Royal Soc Chemistry2024

Role of Carbonyl Compounds for N-Nitrosamine Formation during Nitrosation: Kinetics and Mechanisms

Urs von Gunten, Florian Frédéric Vincent Breider, Yishuai Pan

N-Nitrosamines are potential human carcinogens frequently detected in natural and engineered aquatic systems. This study sheds light on the role of carbonyl compounds in the formation of N-nitrosamines by nitrosation of five secondary amines via different ...

2024

Achieving realistic ozonation conditions with synthetic water matrices comprising low-molecular-weight scavenger compounds

Urs von Gunten

Ozonation is used worldwide for drinking water disinfection and increasingly also for micropollutant abatement from wastewater. Identification of transformation products formed during the ozonation of micropollutants is challenging due to several factors i ...

PERGAMON-ELSEVIER SCIENCE LTD2024

Oxidation processes and me

Urs von Gunten

This publication summarizes my journey in the field of chemical oxidation processes for water treatment over the last 30+ years. Initially, the efficiency of the application of chemical oxidants for micropollutant abatement was assessed by the abatement of ...

Pergamon-Elsevier Science Ltd2024