The formation of hydroxyl radicals during hydrodynamic cavitation in microfluidic reactors using salicylic acid dosimetry

Maleki, Mohammadamin (avtor), Talabazar, Farzad Rokhsar (avtor), Davoudian, Salar Heyat (avtor), Dular, Matevž (avtor), Koşar, Ali (avtor), Petkovšek, Martin (avtor), Šmid, Alenka (avtor), Zupanc, Mojca (avtor), Ghorbani, Morteza (avtor)

Cavitation is a phase change phenomenon that generates highly energized bubbles due to low local pressures. The collapse of these bubbles releases this energy to the surrounding area in different forms upon the pressure recovery. Free radical production, which is considered as chemical effect of the bubble collapse, plays a major role in many applications, from wastewater treatment to material exfoliation. Although some studies underscore the importance of chemical effects for acoustic cavitation (AC), their investigations in hydrodynamic cavitation (HC) are challenging due to the difficulty in controlling cavitating flows. One of the approaches that could shed light on this challenging aspect is to shrink the reactor scale to micro-scale size (“HC on a chip”). In this regard, we investigated the chemical effects of HC using Salicylic Acid (SA) dosimetry in three different micro-scale designs (long diaphragm, micro-orifice, and micro-venturi configurations) and compared the results to those of a macro-scale HC reactor. High-speed visualization revealed important links between flow patterns and the formation of hydroxyl radicals (•OH), which contributed to the SA products. This study thus focused on comparing the effectiveness of the three micro-scale reactors in terms of •OH formation. According to the results, the “HC on a chip” concept demonstrated significantly higher efficiency in generating SA products compared to the macro-scale HC reactor. For instance, the micro-scale HC reactors achieved an SA concentration of approximately 0.6 μg/mL in just 5 cycles, while the macro-scale HC reactor required 164 cycles to reach a similar concentration (0.45 μg/mL). This substantial reduction in the number of cycles highlights the potential of micro-scale HC reactors for efficient and rapid generation of SA products.

• Jezik: Angleški jezik
• Ključne besede: hydrodynamic cavitation, microfluidic reactors, chemical effects, hydroxyl radical, salicylic acid
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FS - Fakulteta za strojništvo ; FFA - Fakulteta za farmacijo
• Status publikacije: Objavljeno
• Različica publikacije: Recenzirani rokopis
• Leto izida: 2025
• Št. strani: 12 str.
• Številčenje: Vol. 511, art. 161976
• PID: 20.500.12556/RUL-168390
• UDK: 532.528:66
• ISSN pri članku: 1873-3212
• DOI: 10.1016/j.cej.2025.161976
• COBISS.SI-ID: 230634243
• Datum objave v RUL: 11.04.2025

Gradivo je del revije

• Naslov: Chemical engineering journal
• Založnik: Elsevier
• ISSN: 1873-3212
• COBISS.SI-ID: 23123973

Licence

• Licenca: CC BY-NC-ND 4.0, Creative Commons Priznanje avtorstva-Nekomercialno-Brez predelav 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc-nd/4.0/deed.sl
• Opis: Najbolj omejujoča licenca Creative Commons. Uporabniki lahko prenesejo in delijo delo v nekomercialne namene in ga ne smejo uporabiti za nobene druge namene.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: hidrodinamska kavitacija, mikrofluidika, kemijski učinki, salicilna kislina, hidroksilni radikal