Corrosion Inhibition on Carbon Steel by Reaction Products of Glucose and Glycine

Abstract

In order to understand the corrosion inhibition effect of the reaction products of glucose and glycine (PGG) on carbon steel, the weight loss measurement, electrochemical techniques, and SEM observation were employed to study the corrosion inhibition of PGG on carbon steel in 1 mol/L HCl solution. Results showed that PGG showed good corrosion inhibition effect on carbon steel, and the corrosion inhibition efficiency enhanced with the increase of PGG concentration. When the highest concentration of PGG was 250 mg/L, it showed the best corrosion inhibition effect, the inhibition efficiency reached the maximum of 94.7%, which had the decreasing tendency with increasing corrosion temperature. Moreover, PGG was a mixed type corrosion inhibitor by retarding both cathodic reduction reaction and anodic oxidation reaction process of carbon steel electrode simultaneously. The good corrosion inhibition was mainly due to combination of physical and chemical adsorption of multi phase to form a protective film covering on the surface of carbon steel that isolated the carbon steel from the acid solution and thereby suppressed carbon steel corrosion. PGG adsorption on the carbon steel surface followed the Langmuir adsorption isotherm model. In general, the product of glucose and glycine (PGG) was an excellent corrosion inhibitor for carbon steel in 1 mol/L HCl solution.

Keywords

• carbon steel|acid corrosion|corrosion inhibitor|electrochemical techniques|langmuir adsorption isotherm model