Inhibition of corrosion of C38 steel in 1 M H3PO4 medium by an esomeprazole drug waste

In the present work, the corrosion inhibitory effect of Esomeprazole drug waste (EDW) on C38 steel in 1.0 M H3PO4 medium has been studied.The choice of this medical waste was made with the aim of recovering it for reuse in corrosion inhibition.This effect of inhibition has been evaluated by Tafel polarization and electrochemical impedance spectroscopy.The surface morphology has been characterized by scanning electron microscopy and energy-dispersive Xray spectroscopy.Tafel polarization analysis shows that EDW is a mixed inhibitor.The results obtained by electrochemical impedance spectroscopy show that the inhibitory effect increases with increasing inhibitor concentration.The results obtained from different testing techniques show that the use of Esomeprazole in a phosphoric acid medium can inhibit the corrosion of C38 steel up to 99.52% at a concentration of 10 -4 M of Esomeprazole.The analysis of results obtained by scanning electron microscopy and energy-dispersive X-ray spectroscopy allowed to addition of Esomeprazole resulted in the creation of a considerably less damaged surface.The results of DFT and MD simulations were used to illustrate the effect of molecular structure on corrosion inhibition efficiency and to model the adsorption of Esomeprazole on the C38 surface.The corrosion rate is relative to pH measured by Strehlow's acidity function.