Effect of inorganic anions on the titanium dioxide-based photocatalytic oxidation of aqueous ammonia and nitrite

Influence of pH and pH adjustment conditions on photocatalytic oxidation of aqueous ammonia under airflow over Pt-loaded TiO2

“…Several studies have investigated wastewater purification by the photocatalytic oxidation of aqueous ammonia using TiO 2 and/or PtTiO 2 [9][10][11][12][13][14]. Some of these studies reported the effect of pH [9,10], whereas others focused on the effects of Pt loading on the TiO 2 [13] or the presence of inorganic anions [14].…”

UVA-Induced Processes in the Aqueous Titanium Dioxide Suspensions Containing Nitrite (An EPR Spin Trapping Study)

“…Moreover, the reactive radical species generated upon TiO 2 photoexcitation in such systems (  OH, O 2 -/  O 2 H) can participate in a variety of reactions with nitrite or its photolytic products (8). The mechanism of the photocatalytic oxidation of nitrite to nitrate upon TiO 2 irradiation was proposed previously (23)(24)(25)(26). The impact of TiO 2 loading and pH on phenol photonitration upon UV irradiation of nitrite was also investigated (22).…”

A new sensor for ammonia based on cyanidin-sensitized titanium dioxide film operating at room temperature

“…Occupational safety and health administration (OSHA) has set a 15 min exposure limit for gaseous ammonia by a volume of 35 ppm in environmental air. In the past decade, many kinds of ammonia sensors have been developed based on different sensing mechanisms [1,2,[5][6][7][8][9]. These include electrical [10], mass [11], or optical-based methods [12].…”

“…It has been established that the sensing properties of the films are improved by decreasing the grain size of the TiO 2 so as to increase the surface to volume ratio of the films [6]. Films with nanometre-sized TiO 2 particles have thus proved to be a leading candidate metal-oxide semiconductor for gas sensing.…”

“…Films with nanometre-sized TiO 2 particles have thus proved to be a leading candidate metal-oxide semiconductor for gas sensing. Films based on TiO 2 also respond to ammonia [6,13]. The TiO 2 sensing films described so far operate at high temperatures (250-450 • C) [14,15] or use alternating currents.…”