Control of chloride ion corrosion by MgAlOx/MgAlFeOx in the process of chloride deicing

Abstract

The corrosion inhibitor that is added to chloride deicing salt, whose anti-corrosion and low pollution is great signi cance. LDHs, calcined at high temperature were used as adsorbents to remove various anionic contaminants and it could reduce the solution's freezing point after adsorbing anions. Therefore, this paper reports the use of calcined LDHs as corrosion inhibitors in deicing salts. We analyzed that the removal ability of chloride ion MgAlFeO x was stronger than that of MgAlO x , reaching 85.50%, and the freezing point was lower than that of MgAlO x , the value was -12.0 °C. At the same time, we also found that CaCl 2 -MgAlO x and CaCl 2 -MgAlFeO x signi cantly reduce the corrosion of carbon steel and concrete compared with chloride salts, and CaCl 2 -MgAlFeO x has the lowest corrosion degree. Hence, we determined that MgAlFeO x was corrosion inhibitor in chloride deicing salt. The metal molar ratio, synthesis temperature and calcination temperature for preparation of MgAl/MgAlFe-LDHs were determined by XRD and TG-DSC analysis that are 9/2/1, 120 ºC and 500 ºC, respectively. The characteristics of MgAlFeO x after Fe 3+ addition were studied in detail by Zeta, XRD, XPS, BET and SEM.The mechanism of corrosion inhibitor's anticorrosion was determined, which was achieved by adsorption and neutralization.