Corrosion Inhibition of Carbon Steel in SULFIRAN® Process

Document Type : Research Paper


1 Corrosion Department, Research Institute of Petroleum Industry (RIPI), Tehran, Iran

2 Engineering and Process Development Division, Research Institute of Petroleum Industry (RIPI), Tehran, Iran

3 Gas Science Department, Research Institute of Petroleum Industry (RIPI), Tehran, Iran

4 Development and Optimization of Energy Technologies Division, Research Institute of Petroleum Industry (RIPI), Tehran, Iran


In this investigation, attempts were directed to study the inhibitive effects of nitrite and phosphate base inhibitors for the carbon steel alloy samples, which are used in an acid gas treatment process (The SULFIRAN® solution), in Fe-EDTA solution. Electrochemical techniques, i.e. polarization curves and electrochemical impedance spectroscopy (EIS), were used to evaluate the inhibition efficiency. Linear polarization resistance (LPR) and weight loss techniques were also used to determine the corrosion rate for the pilot tests. The results indicated that adding inhibitors reduced corrosion rate to some suitable values (


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