Eosin as Corrosion Inhibitor for Carbon Steel in Well Water

Abstract

The inhibition efficiency of Eosin in controlling corrosion of carbon steel immersed in well water, has been evaluated by mass loss method both in absence and presence of zinc ion. A synergistic effect exists between Eosin (EN) and Zn 2+ . The inhibition efficiency (IE) of the EN - Zn 2+ system decreases with increase in immersion period. Addition of N-cetyl-N,N,N-trimethylammonium bromide (CTAB), sodium dodecyl sulphate (SDS), sodium sulphite (Na2SO3) does not change the excellent inhibition efficiency of the EN-Zn 2+ system. Polarization study suggests that the EN-Zn 2+ system functions as an anodic inhibitor system. AC impedance spectra reveal the presence of a protective film on the metal sur- face. FTIR spectra indicate that the protective film consists of Fe 2+ - EN complex and Zn(OH)2.