Evaluation of Expired Moxifloxacin Drug as Corrosion Inhibitor for Copper in Synthetic Acid Rain (SAR) Solution

This paper evaluated the possibility of using quinoline derivative (an expired Moxifloxacin) as an inhibitor for copper corrosion in synthetic acid rain (SAR) solution. Weight reduction (WR) experiments, potentiodynamic polarization (PDP) and AC impedance spectra (EIS) were employed to investigate corrosion inhibition (ƞ%) and inhibition rates. (ƞ%) increases by increasing the concentration of MOXI in all test methods. The PDP curves indicated that this expired medication exhibited mixed-type inhibitory activity. According to the EIS tests, the ƞ % was found to improve with raising the MOXI concentration and reached 94.05% at 600 ppm. On the other hand, the ƞ% was lowered by raising the temperature. The adsorbed MOXI molecules on copper obey Langmuir isotherm model. Furthermore, scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FT-IR) are employed to examine the surface of the copper sample. The results acquired experimentally were validated through the application of density functional theory (DFT) and molecular simulation (MC) in theoretical calculations. All the tests metthods gave similar results.