Enhanced corrosion inhibition effect of sodium tartrate on copper in potable water

Abstract

In this study we have reported sodium tartrate (ST) and Zn2+ as the potential mixed corrosion inhibitors for copper corrosion in drinking water, by using electrochemical impedance and polarization techniques. The results of potentio-dynamic polarization indicated that sodium tartrate could be used as mixed type inhibitor with Zn2+. ST was found to be 92% effective for slowing down both the anodic and cathodic reaction rates. It was additionally found that ST could coat the surface of copper to prevent it from conducting electricity. As the inhibitor concentration increased, the stability of the formed protective layer was also improved. The results obtained from studies like SEM, EDAX, AFM, and water contact angle clearly indicated the development of a barrier by inducing the lotus effect on copper surface. The water contact angle measurement results suggested that the coating formed in the presence of inhibitor was superhydrophobic, and the surface was homogeneous.