Corrosion Inhibitive Behaviour of the Natural Honey in Acidic Medium of A315 Mild and 304 Austenitic Stainless Steels

Document Type : Original Article


The corrosion inhibition performance of the natural honey in H2SO4 acidic medium
containing mild steel and stainless steel, using weight loss and electrochemical techniques was
investigated. The study involved the determination of the effects of the variation of the
concentrations of natural honey inhibitor on the corrosion process. Potentiodynamic
polarization for the electrochemical measurements was carried out by using Autolab PGSTAT
101 Metrohm potentiostat. Results obtained showed that increase in natural honey
concentration (0–10 v/v%) retards the rate of metal dissolution and hence inhibits the corrosion
of the metals. And the efficiency of the natural honey inhibitor increased with increased
inhibitor concentration. The Tafel plots showed that the natural honey significantly decreased
the corrosion potential (Ecorr) and current density (Jcorr); but increased the surface coverage (πœƒπœƒ)
and polarisation resistance. Adsorption and thermodynamics studies revealed that the
Langmuir adsorption isotherm was obeyed and the large values of βˆ†πΊπΊπ‘Žπ‘Žπ‘Žπ‘Žπ‘Žπ‘Žobtained as well as its
negative sign implied strong interaction and high efficiency of adsorption. SEM analysis of the
metals (before and after corrosion) revealed significant reduction in corrosion rate as the
concentrations of natural honey inhibitor increased.