Sonophotocatalytic efficiency of nickel and copper supported ferrite nanoparticles doped MWCNTs nanocatalyst as a novel catalyst for amoxicillin degradation

The main objective of this study was to evaluate the potential for amoxicillin (AMX) degradation in a sonophotocatalytic system employing a nickel-copper supported ferrite nanoparticle-doped MWCNTs nanocatalyst (NCFM). Our target catalyst was prepared based on the coprecipitation method, and its synthesis was verified by undergoing various techniques, including FTIR, XRD, FESEM/EDX, BET, and TEM. Best results in terms of AMX, COD, and TOC removal efficiencies were recognized in the optimum values of the parameters so that their removal efficiencies were 100%, 95%, and 93%, respectively. The observed optimum values were 25 mg. L⁻¹ AMX, pH of 3, photocatalyst mass of 0.6 g.L⁻¹, time of 40 min, ultrasonic wave frequency of 35 kHz, and UV intensity of 24 W. According to kinetic studies, the sonophotcatalytic process in the presence of NCFM was found to be more successful in degrading AMX compared to other assessed processes, i.e., sonolysis, photolysis, photocatalysis, and sonocatalysis. Moreover, hydroxyl radical (^•OH) and hole (h⁺) were proven to be effective in AMX degradation, based on scavenging tests. A 5-run cycle test evaluating the stability and reusability of our studied catalyst confirmed an efficiency of 95.2% for the last run. Employing our evaluated process was associated with producing degradable effluents (according to high BOD₅/COD and BOD₅/TOC ratios) and improved results in terms of reducing toxicity (based on results of Escherichia coli (E. coli) growth inhibition rate). Moreover, the utilized system exhibited the ability to mineralize AMX to NH₄⁺, NO₃^-, SO₄^2-, CO₂, and H₂O. The above observations could be considered confirmative data for the successful application of the studied system with NCFM for degrading AMX.