Successive advanced oxidation of pyridine by ultrasonic irradiation: effect of additives and kinetic study

Abstract

Pyridine has received considerable attention from environmental scientists and engineers, due to its undesirable effect in the water environment. Pyridine contaminated wastewater presents a great threat on water resources safety. In this research, the degradation and advanced oxidation of pyridine in aqueous solution by ultrasonic waves were studied under various process variables including different initial concentration, H₂O₂, NaCl, and Fenton reagent. The results show that the degradation efficiency of pyridine decreases with the increasing of the initial concentration of pyridine. The removal rates of pyridine decreased from 52 to 15% with increasing the initial concentration from 10 to 100 mg/L. In the concentration range studied, the amount of H₂O₂ and NaCl added has positive contribution on the degradation of pyridine. The removal effect of ultrasound and Fenton is better than ultrasound or H₂O₂ alone acting on pyridine. A possible degradation pathway for pyridine was also proposed. In the end, it could be proposed that ultrasonic irradiation was an effective method for the removal of pyridine from wastewater.

Keywords:

• Pyridine
• Ultrasonic irradiation
• Wastewater treatment
• Fenton reagent