Sonochemical processes for the degradation of antibiotics in aqueous solutions: A review

Abstract

Antibiotic residues in water are general health and environmental risks due to the antibiotic-resistance phenomenon. Sonication has been included among the advanced oxidation processes (AOPs) used to remove recalcitrant contaminants in aquatic environments. Sonochemical processes have shown substantial advantages, including cleanliness, safety, energy savings and either negligible or no secondary pollution. This review provides a wide overview of the different protocols and degradation mechanisms for antibiotics that either use sonication alone or in hybrid processes, such as sonication with catalysts, Fenton and Fenton-like processes, photolysis, ozonation, etc.

Keywords: Antibiotic degradation; Sonication; Sono/Fenton; Sonocatalysis; Sonophotocatalysis; Sonozonation.

Graphical abstract

Scheme 1

Pathway of intermediate formation in the sonolytic degradation of SMZ .

Fig. 1

Schematic diagram of ultrasonic horn-type (a) and bath-type (b) setups for degradation. Reprinted from ref. Copyright (2006), with permission from Elsevier.

Fig. 2

The mechanisms of antibiotic removal by sonocatalysis.

Fig. 3

Mechanism schematic of sono/Fenton-like processes. Reprinted from ref. Copyright (2016), with permission from Elsevier.

Scheme 2

A tentative partial degradation pathway of LEV in a sono/H₂O₂/Fe₃O₄ (magnetic nanoparticles) system. Reprinted from ref. Copyright (2015), with permission from Elsevier.

Scheme 3

Proposed degradation pathway for the TC antibiotic in a sono/S₂O₈²⁻ process. Reprinted from ref. Copyright (2017), with permission from Elsevier.

Fig. 4

SMZ degradation by different processes: US, PMS and US/PMS systems. Reprinted from ref. Copyright (2018), with permission from Elsevier.

Scheme 4

The degradation mechanism of SDZ by sono/Fe⁰/PS. Reprinted from ref. Copyright (2014), with permission from Elsevier.

Scheme 5

Proposed SDZ degradation pathways in the sono/Fe⁰/PS system. Reprinted from ref. Copyright (2014), with permission from Elsevier.

Fig. 5

Degradation mechanisms of TC by sonophotocatalysis. Reprinted from ref. Copyright (2019), with permission from Elsevier.

Scheme 6

Pathway of intermediate formation during the degradation of AMX by sonication alone, ozonation alone and sonozonation at pH 10, 575 kHz, 75 W, 15 mg/L O₃(aq). Reprinted from ref. Copyright (2012), with permission from Elsevier.

Scheme 7

The degradation pathway of TC in the sonozonation system. Reprinted from ref. Copyright (2012), with permission from Elsevier.