Single and Double Alkyl Chain Quaternary Ammonium Salts as Environment-Friendly Corrosion Inhibitors for a Q235 Steel in 0.5 mol/L H[sub.2]SO[sub.4] Solution

In this work, the corrosion inhibition effects of octadecyl trimethyl ammonium chloride (OTAC) and dioctadecyl dimethyl ammonium chloride (DDAC) on Q235 steel in a 0.5 mol/L H[sub.2]SO[sub.4] solution are studied. The results of the electrochemical experiment, contact angle measurement, and scanning electron microscopy indicate that the two ionic liquids belong to mixed-type corrosion inhibitors with good anti-corrosion performance. Additionally, OTAC has a better anti-corrosion ability than DDAC, implying that the steric hindrance effect of the double alkyl chain is not conducive to the adsorption of DDAC on the electrode surface.