Effect of Hydrogen Peroxide Addition on the Photochemical and Sonochemical Destruction of Pyridine in Wastewater

Document Type : Original Article

Author

Egyptian Armed Forces, Cairo, Egypt. Corresponding author. Tel.:+201141750544; fax: +222621918.

Abstract

Abstract Pyridine and its derivatives have potential impact to various environment segments due to its persistent nature and are normally found in wastewater. The photochemical and sonochemical degradation of aqueous solutions of pyridine have been investigated by means of ultraviolet (UV), ultrasound (US), UV/H2O2 and US/H2O2 irradiation processes. The pure photochemical process demonstrated to be efficient for degradation of low initial concentrations of pyridine (10ppm). While sonochemical degradation proceeded very slowly, leading to less than 53% of pyridine removal after 200 min. The degradation efficiency was increased with increase H2O2 concentration; however, the marginal benefit became decreasing with further increasing of H2O2 due to the scavenging effect of excess H2O2. The kinetics of photochemical and sonochemical degradation of pyridine were found to follow a first-order rate law. A possible degradation pathway for pyridine was also proposed.

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