Ultrasonic Irradiation of p-Nitrophenol in Aqueous Solution

Article abstract of DOI:10.1021/j100162a037

The kinetics and mechanism of the sonochemical reactions of p-nitrophenol have been investigated in oxygenated aqueous solutions.In the presence of ultrasound (20 kHz, 84 W) p-nitrophenol was degraded primarily by denitration to yield NO2^-, NO3^-, benzoquinone, hydroquinone, 4-nitrocatechol, formate, and oxalate.These reaction products and the kinetic observations are consistent with a model involving high-temperature reactions of p-nitrophenol in the interfacial region of cavitation bubbles.The main reaction pathway appears to be carbon-nitrogen bond cleavage.Reaction with hydroxyl radicals provides a secondary reaction channel.The average effective temperature of the interfacial region surrounding the cavitation bubbles was estimated to be T ca. 800 K.