Identification of active sonochemical zones in a triple frequency ultrasonic reactor via physical and chemical characterization techniques

T Joyce Tiong; Derick K L Liew; Ramona C Gondipon; Ryan W Wong; Yuen Ling Loo; Matthew S T Lok; Sivakumar Manickam

doi:10.1016/j.ultsonch.2016.04.029

Identification of active sonochemical zones in a triple frequency ultrasonic reactor via physical and chemical characterization techniques

Ultrason Sonochem. 2017 Mar;35(Pt B):569-576. doi: 10.1016/j.ultsonch.2016.04.029. Epub 2016 Apr 26.

Authors

T Joyce Tiong¹, Derick K L Liew¹, Ramona C Gondipon¹, Ryan W Wong¹, Yuen Ling Loo¹, Matthew S T Lok¹, Sivakumar Manickam²

Affiliations

¹ Department of Chemical and Environmental Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia.
² Department of Chemical and Environmental Engineering, University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor, Malaysia. Electronic address: Sivakumar.Manickam@nottingham.edu.my.

PMID: 27156122
DOI: 10.1016/j.ultsonch.2016.04.029

Abstract

Coupling multiple frequencies in ultrasonic systems is one of the highly desired area of research for sonochemists, as it is known for producing synergistic effects on various ultrasonic reactions. In this study, the characteristics of a hexagonal-shaped triple frequency ultrasonic reactor with the combination frequencies of 28, 40 and 70kHz were studied. The results showed that uniform temperature increment was achieved throughout the reactor at all frequency combinations. On the other hand, sonochemiluminescence emission and degradation rate of Rhodamine B varies throughout different areas of the reactor, indicating the presence of acoustic 'hot spots' at certain areas of the reactor. Also, coupling dual and triple frequencies showed a decrease in the hydroxyl radical (OH) production, suggesting probable wave cancelling effect in the system. The results can therefore be served as a guide to optimize the usage of a triple frequency ultrasonic reactor for future applications.

Keywords: Cavitation; Characterization; Degradation; Reactor; Triple frequency; Ultrasound.