Sodium nitrite as corrosion inhibitor for mild steel in simulated concrete pore solution

The corrosion inhibition effect of mild steel in si mulated concrete pore solution (SCPS) by Sodium N itrite and Zn has been investigated using weight loss method and cyclic voltammetry. The results show that 93% of i nhibition efficiency is achieved with binary system consistin g of 100 ppm of sodium nitrite – 50 ppm of Zn 2+ . Surface evaluation technique like FTIR is used to determi ne the nature of the protective film formed on the metal surface. The protective film consists of Fe 2+ SN complex, Zn SN complex and Zn(OH) 2. Cyclic voltammetry study reveals that the protective film is more compact and stable ev n in 3.5% NaCl environment.