Impact of sonication power on the degradation of paracetamol under single- and dual-frequency ultrasound

Mehrdad Zare; Madeleine J Bussemaker; Efraím A Serna-Galvis; Ricardo A Torres-Palma; Judy Lee

doi:10.1016/j.ultsonch.2023.106564

Impact of sonication power on the degradation of paracetamol under single- and dual-frequency ultrasound

Ultrason Sonochem. 2023 Oct:99:106564. doi: 10.1016/j.ultsonch.2023.106564. Epub 2023 Aug 19.

Authors

Mehrdad Zare¹, Madeleine J Bussemaker¹, Efraím A Serna-Galvis², Ricardo A Torres-Palma³, Judy Lee⁴

Affiliations

¹ School of Chemistry and Chemical Engineering, University of Surrey, Guildford GU2 7XH, United Kingdom.
² Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 # 52-21, Medellín, Colombia; Catalizadores y Adsorbentes (CATALAD), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 # 52-21, Medellín, Colombia.
³ Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 # 52-21, Medellín, Colombia.
⁴ School of Chemistry and Chemical Engineering, University of Surrey, Guildford GU2 7XH, United Kingdom. Electronic address: j.y.lee@surrey.ac.uk.

Abstract

The effects of sonication power on the ultrasonic cavitation and sonochemistry as well as the degradation of paracetamol were studied and compared for single- and dual-frequency sonoreactors. For the single-frequency sonication, a 500 kHz plate transducer was employed, with three different calorimetric powers of 8.4, 16.7 and 27.9±3.9 W. For the dual-frequency sonication, the plate transducer was perpendicularly coupled with a low-frequency 20 kHz ultrasonic horn, and three calorimetric powers of 27.9, 33.4, 44.6±3.9 W were studied. At all the studied powers, dual-frequency sonication led to a synergistic effect in the degradation of paracetamol, though varying the power of the horn did not affect the degradation rate. A comparison of the degradation data versus the yield of oxidants as well as the overall intensities of sonoluminescence and sonochemiluminescence suggested the degradation is by the action of oxidants near the surface of the bubbles as the major reaction mechanism. Despite the enhancement observed for the degradation, dual-frequency sonication had no significant effect on the yield of either of the oxidants, regardless of the applied power to the horn. In contrast, dual-frequency sonication decreased the overall sonoluminescence and sonochemiluminescence intensities at all powers studied, suggesting that the application of dual-frequency sonication reduces the size of cavitation bubbles. Normal distribution function analysis confirmed dual-frequency sonication resulted in smaller sonoluminescing bubbles, hence the reduction in the sonoluminescence intensity. The increase in degradation rate under DFUS is attributed to the increase in the transfer of paracetamol from the bulk towards the bubbles. As a result, the availability of the pollutant molecules in the vicinity of the bubbles to react with HO• would increase and consequently, the degradation rate would enhance under DFUS.

Keywords: Cavitation; Dosimetry; Dual-frequency ultrasound; Pharmaceuticals sonodegradation; Power effects; Sonochemiluminescence; Sonoluminescence.