Study the Corrosion Inhibition on the Iraqi Fuel Tanks using Cefoperazone Drug

Abstract

Corrosion is one of the most important problems that face the petroleum industry, both production and refining, and cause damage to petroleum equipment, tanks, and transmission lines, and increasing maintenance costs. in this study , was adding six concentrations of the drug expired Cefoperzone (Exp CEF) (50, 100, 200, 300, 400, and 500 ppm) to a Simulated Oil Well Water (SOWW), the inhibitive role of (Exp CEF) drug was investigated to Reduce the corrosion risk of carbon steel. Four different temperatures were used to conduct electrochemical tests (303, 313, 323 and 333 K) to achieve the study. The study was then supported by an examination of the inhibited surface using field emission scanning electron microscopy with energy dispersive (FESEM) and (AFM). The results indicated occurring the inhibition by an anodic inhibitor that controls the dissolution of iron from steel gave the highest inhibition efficiency (IE%) by adding 500 ppm, while the calculation of polarization resistance (Rp) gave the highest resistance by 400 ppm through adsorption the added drug to show flakes shaped structures with decreasing surface roughness (Ra ) from 307.1 to 83.15 after inhibition. The calculation of adsorption isotherm confirmed the obeying of Langmuir adsorption isotherm by giving the coefficient of linear regression was about one in the range of 0.999 > R^2 > 0.995, with the spontaneous adsorption that estimated from the negative values of 〖∆H〗_ads^o and variation in the type of adsorption to be physically or chemically according to the added concentration because of the differential sign of 〖∆H〗_ads^o . The sign of 〖∆H〗_ads^o was positive that reflecting the increase in randomness at the metal/solution interface.