INHIBITION OFCORROSION OF CARBON STEEL IN SEA WATER BY HYDROXY PROLINE – Ni2+ SYSTEM

Abstract

The corrosion inhibition effect of carbon steel in sea water environment by HydroxyProline (HP)-Ni2+ system has been investigated using weight loss method. The results show that 92% inhibition efficiency (IE) achieved with binary system consisting of 300 ppm of HP and 30 ppm of Ni2+. The addition of 50 ppm of sodium gluconate (SG) on HP- Ni2+ system increased the IE from 92% to 98%. The influence of sodium gluconate (SG) on HP- Ni2+ system control the microbial corrosion. FTIR investigate the nature of the protective film formed on the metal surface. The protective film consists of Fe2+–HP complex, Fe2+–SG complex and Ni(OH)2. SEM used to prove the formation of protective film. The mechanistic aspects of corrosion inhibition based on the results obtained from the weight-loss method and the electrochemical method viz., potentiodynamic polarization