Some observations about the photocatalytic oxidation of cyanate to nitrate over TiO2

✍ Scribed by Agustín Bravo; Josep Garcia; Xavier Domènech; José Peral

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 297 KB
• Volume: 39
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(94)e0072-v

✦ Synopsis

The photocatalytic oxidation of cyanate ions in aqueous solution and in the presence of TiO, takes place by two different reaction pathways, depending on the solution pH. For pHs lower than 10, the main oxidation product is nitrate-instead of N2, as reported previously. The hydrolysis of cyanate seems to be the reason for this change of mechanism with pH. NH: is formed by CNO-hydrolysis. and its photo-oxidation gives nitrite and-nitrate. The hydrolysis rate controls the speed of the wholeSprocess, but the photo-oxidation of CNO-to N, appeared to be faster in a strongly basic medium. For values of pH lower than 5, NH: is hardly oxidized, remaining stable in solution.