Publications de Silvio Canonica

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke, Joanna Maria Houska

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Enhanced transformation of aquatic organic compounds by long-lived photooxidants (LLPO) produced from dissolved organic matter

Silvio Canonica, Urs von Gunten, Stephanie Christa Remke

Dissolved organic matter (DOM) plays a crucial role in the photochemical transformation of organic contaminants in natural aquatic systems. The present study focuses on the characterization of a specific effect previously observed for electron-rich phenols ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Micropollutants as internal probe compounds to assess UV fluence and hydroxyl radical exposure in UV/H 2 O 2 treatment

Silvio Canonica, Fabienne Eugster, Urs von Gunten, Robin Wünsch, Thomas Wintgens

Organic micropollutants (MPs) are increasingly detected in water resources, which can be a concern for human health and the aquatic environment. Ultraviolet (UV) radiation based advanced oxidation processes (AOP) such as low-pressure mercury vapor arc lamp ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Laser flash photolysis study of the photoinduced oxidation of 4-(dimethylamino)benzonitrile (DMABN)

Silvio Canonica, Frank Jonathan Leresche, Urs von Gunten

Aromatic amines are aquatic contaminants for which phototransformation in surface waters can be induced by excited triplet states of dissolved organic matter ((DOM)-D-3*). The first reaction step is assumed to consist of a one-electron oxidation process of ...

ROYAL SOC CHEMISTRY2019

Effects of Ozone on the Photochemical and Photophysical Properties of Dissolved Organic Matter

Silvio Canonica, Frank Jonathan Leresche, Urs von Gunten

This study focused on the effects of ozonation on the photochemical and photophysical properties of dissolved organic matter (DOM). Upon ozonation, a decrease in DOM absorbance was observed in parallel with an increase in singlet oxygen (O-1(2)) and fluore ...

AMER CHEMICAL SOC2019

Effects of ozone on the dissolved organic matter and insights on the photophysic that govern to the formation of reactive intermediates photoproduction

Silvio Canonica, Frank Jonathan Leresche, Urs von Gunten

AMER CHEMICAL SOC2019

Characterization of changes in dissolved organic matter properties and disinfection byproduct formation during solar photolysis of aqueous free chlorine

Silvio Canonica, Urs von Gunten

2018

Abatement of Polychoro-1,3-butadienes in Aqueous Solution by Ozone, UV Photolysis, and Advanced Oxidation Processes (O-3/H2O2 and UV/H2O2)

Silvio Canonica, Urs von Gunten, Minju Lee

The abatement of 9 polychloro-1,3-butadienes (CBDs) in aqueous solution by ozone, UV-C(254 nm) photolysis, and the corresponding advanced oxidation processes (AOPs) (i.e., O-3/H2O2 and UV/H2O2) was investigated. The following parameters were determined for ...

American Chemical Society2017

Degradation rates of benzotriazoles and benzothiazoles under UV-C irradiation and the advanced oxidation process UV/H2O2

Silvio Canonica, Urs von Gunten

Benzotriazoles (BTs) and benzothiazoles (BTHs) are extensively used chemicals found in a wide range of household and industrial products. They are chemically stable and are therefore ubiquitous in the aquatic environment. The present study focuses on the p ...

Elsevier2015

Photosensitizing and Inhibitory Effects of Ozonated Dissolved Organic Matter on Triplet-Induced Contaminant Transformation

Silvio Canonica, Urs von Gunten

Dissolved organic matter (DOM) is both a promoter and an inhibitor of triplet-induced organic contaminant oxidation. This dual role was systematically investigated through photochemical experiments with three types of DOM of terrestrial and aquatic origins ...

American Chemical Society2015

Comparison of a novel extraction-based colorimetric (ABTS) method with membrane introduction mass spectrometry (MIMS): Trichloramine dynamics in pool water (vol 58, pg 258, 2014)

Silvio Canonica, Urs von Gunten

Elsevier2015

Chemical Oxidation of Dissolved Organic Matter by Chlorine Dioxide, Chlorine, And Ozone: Effects on Its Optical and Antioxidant Properties

Silvio Canonica, Urs von Gunten

In water treatment dissolved organic matter (DOM) is typically the major sink for chemical oxidants. The resulting changes in DOM, such as its optical properties have been measured to follow the oxidation processes. However, such measurements contain only ...

Amer Chemical Soc2013

Enhanced N-nitrosamine formation in pool water by UV irradiation of chlorinated secondary amines in the presence of monochloramine

Silvio Canonica, Urs von Gunten, Minju Lee

N-Nitrosamines, in particular N-nitrosodimethylamine (NDMA), are carcinogens, which occur as chlorine disinfection by-products (DBPs) in swimming pools and hot tubs. UV treatment is a commonly used technique in swimming pools for disinfection and DBP atten ...

Elsevier2013

Dissolved organic matter as a photosensitizer and an inhibitor of triplet-induced transformation of water contaminants

Silvio Canonica, Urs von Gunten

Amer Chemical Soc2013

Enhanced N-nitrosamine formation in pool water by UV irradiation of chlorinated secondary amines in presence of monochloramine

Silvio Canonica, Urs von Gunten, Minju Lee

Amer Chemical Soc2013

Oxidation of dissolved organic matter with ozone, chlorine, and chlorine dioxide: Effects on optical and antioxidant properties

Silvio Canonica, Urs von Gunten

Amer Chemical Soc2013

Benzotriazoles: Reactivity toward UV-C light and the hydroxyl radical, and removal by the UV/H2O2 process

Silvio Canonica, Urs von Gunten

Amer Chemical Soc2013

Advanced oxidation processes for the degradation of CCL3 compounds: Assessment of the toxicity of transformation products

Silvio Canonica, Kristin Schirmer, Urs von Gunten

Amer Chemical Soc2013

Removal of the antiviral agent oseltamivir and its biological activity by oxidative processes

Silvio Canonica, Kristin Schirmer, Urs von Gunten

The antiviral agent oseltamivir acid (OA, the active metabolite of Tamiflu) may occur at high concentrations in wastewater during pandemic influenza events. To eliminate OA and its antiviral activity from wastewater, ozonation and advanced oxidation proces ...

2012