Catalytic activation of hydrogen peroxide by Cr2AlC MAX phase under ultrasound waves for a treatment of water contaminated with organic pollutants

• Published in: Ultrasonics sonochemistry Vol. 93; p. 106294
• Main Authors: Alimohamadi, Monireh, Khataee, Alireza, Arefi-Oskoui, Samira, Vahid, Behrouz, Orooji, Yasin, Yoon, Yeojoon
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2023; Elsevier
• Subjects: Cr2AlC MAX phase; Cr2AlC/H2O2/ultrasound; Degradation; Organic pollutant; Sonocatalytic activation; Ultrasonic 2D material; Degradation; Sonocatalytic activation; Cr2AlC MAX phase; Organic pollutant; Cr2AlC/H2O2/ultrasound
• ISSN: 1350-4177; 1873-2828; 1873-2828
• DOI: 10.1016/j.ultsonch.2023.106294

[Display omitted] •Preparation and characterization of the Cr2AlC MAX phase.•Efficient activation of H2O2 on Cr2AlC under ultrasonic irradiation.•Degradation of dimethyl phthalate, rifampin, hydroxychloroquine, and acid blue 7.•Association of radical and non-radical species in the degradation of organic pollutants.•Suggesting degradation mechanism considering scavengers and intermediates. This study aims to investigate the sonocatalytic activation of hydrogen peroxide (H2O2) using Cr2AlC MAX phase prepared by the reactive sintering process. The hexagonal structure of the crystalline MAX phase was confirmed by X-ray diffraction. Moreover, the compacted layered structure of the MAX phase was observed via scanning electron microscopy and high-resolution transmission electron microscopy. Under the desired operating conditions, Cr2AlC MAX phase (0.75 g/L) showed suitable potential to activate H2O2 (1 mmol/L) under sonication, thereby allowing a considerable removal efficiency for various organic pollutants, including dimethyl phthalate (69.1%), rifampin (94.5%), hydroxychloroquine (100%), and acid blue 7 (91.5%) with initial concentration of 15 mg/L within 120 min of treatment. Kinetic analysis proved that the degradation reaction followed pseudo-first-order kinetics. Scavenging tests demonstrated that hydroxyl radicals and singlet oxygen were effective species during degradation. Furthermore, a probable mechanism for dimethyl phthalate degradation was suggested according to gas chromatography-mass spectroscopy and nuclear magnetic resonance analyses. The obtained results confirmed the capability of the triple Cr2AlC/H2O2/US process as a promising method for treating contaminated water.