Corrosion inhibition of mild steel by rhodamine B in acid medium

Abstract

<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">Inhibitive action of rhodamine B on corrosion of mild steel in 1.0 M perchloric and phosphoric acid solution has been studied using weight loss, galvanostatic polarization, scanning electron microscopy and electron spectroscopy for chemical analysis techniques at different temperatures 30, 40 and 50°C. It is observed that inhibition efficiency does not show smooth trend with increase in concentration in both acids. Adsorption of rhodamine B follows Langmuir adsorption isotherm and is physical in nature. Polarization studies indicate that inhibitor is of mixed type with slight predominance of anodic character. Activation energy values for corrosion reaction have been calculated for uninhibited as well as for inhibited systems in both the acids investigated.</span>