Corrosion inhibition of steel in a sodium chloride solution by natural honey

Abstract This paper studies the corrosion inhibition of carbon steel in a 0.51 mol × dm −3 sodium chloride solution in the presence of honey. The tests were carried out using the potentiodynamic polarization method, scanning electronic spectroscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FTIR). Electrochemical parameters which indicate the corrosion behavior of the steel in the sodium chloride solution in the absence and in presence of honey were calculated based on the experimental results. It was shown that honey acts as a mixed corrosion inhibitor whose efficiency increases with an increasing concentration. The maximum efficiency of inhibition (77.68 %) was maintained through a 1200 ppm concentration of honey. The adsorption of the tested inhibitor is described by Langmuir's isotherm, and the calculated value of free adsorption energy indicates the physical adsorption of the organic components of honey on the steel surface. The results of the SEM, FTIR and EDX analysis show that the honey covers the steel surface and prevents the influence of the aggressive medium.