Aromatic photonitration in homogeneous and heterogeneous aqueous systems.
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.
Vione
Davide
D
Dipartimento di Chimica Analitica, Università di Torino, Via P. Giuria 5, I-10125 Torino, Italy.
Maurino
Valter
V
Minero
Claudio
C
Vincenti
Marco
M
Pelizzetti
Ezio
E
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
D000336:Aerosols; D004396:Coloring Agents; D006841:Hydrocarbons, Aromatic; D009566:Nitrates; D009573:Nitrites; D014867:Water; C009495:titanium dioxide; D014025:Titanium; D009585:Nitrogen Dioxide