title: Aromatic photonitration in homogeneous and heterogeneous aqueous systems.
abstract: This work describes the nitration of aromatics upon near-UV photolysis of nitrate and nitrite in aqueous solution and upon photocatalytic oxidation of nitrite in TiO2 suspensions. Phenol is used in this work as a model aromatic molecule and as a probe for *NO2/N2O4. The photoinduced nitration of phenol in aqueous systems occurs upon the reaction between phenol and *NO2 or N2O4, and is enhanced by the photocatalytic oxidation of nitrite to *NO2 by TiO2. Aromatic photonitration in the liquid phase can play a relevant role in the formation of nitroaromatics in natural waters and atmospheric hydrometeors, thus being a potential pathway for the condensed-phase nitration of aromatics. Furthermore, the photoinduced oxidation of nitrite to nitrogen dioxide suggests a completely new role for nitrite in natural waters and atmospheric aerosols.
authors.affiliation: Dipartimento di Chimica Analitica, Università di Torino, Via P. Giuria 5, I-10125 Torino, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Vione
authors.forename: Valter
authors.initials: V
authors.lastname: Maurino
authors.forename: Claudio
authors.initials: C
authors.lastname: Minero
authors.forename: Marco
authors.initials: M
authors.lastname: Vincenti
authors.forename: Ezio
authors.initials: E
authors.lastname: Pelizzetti
mesh_terms: D000336:Aerosols; D004396:Coloring Agents / Q000737:chemistry; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D009566:Nitrates / Q000737:chemistry*; D009573:Nitrites / Q000737:chemistry*; D009585:Nitrogen Dioxide / Q000032:analysis; D010777:Photochemistry; D014025:Titanium / Q000737:chemistry; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry
chemical_list: D000336:Aerosols; D004396:Coloring Agents; D006841:Hydrocarbons, Aromatic; D009566:Nitrates; D009573:Nitrites; D014867:Water; C009495:titanium dioxide; D014025:Titanium; D009585:Nitrogen Dioxide