Ionic liquids as corrosion inhibitors for carbon steel protection in hydrochloric acid solution: A first review

Carbon steel is one of the most worldwide applied metallic alloy and commonly used in severe industrial condition specially in the extraction and processing of oil/gas, which make this alloy highly susceptible to corrosion. The use of corrosion inhibitors is mandatory to protect carbon steel in such condition. Conventional corrosion inhibitors, have been for decades the main solution to reduce the corrosive effect on carbon steel. However, the substances used in traditional inhibitors are highly toxic to humans and a threat to the environment. In this context, new substances are being used, such as ionic liquids. This class includes a wide range of molten salts that, owing to their useful combinations of properties are highly effective for many practical applications. In this first review, important advances reported in recent literature are presented, in which the authors applied ionic liquids as corrosion inhibitors for carbon steel in hydrochloric acid. As a comparative effect, all these discussed results were obtained from potentiodynamic polarization tests.(c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Carbon steel is widely used in severe industrial conditions and is highly susceptible to corrosion. Traditional corrosion inhibitors, although effective, are toxic to humans and harmful to the environment. Ionic liquids, as a new alternative, have shown promising results as corrosion inhibitors for carbon steel in hydrochloric acid. This review presents recent advances in the application of ionic liquids for corrosion inhibition, with all results obtained from potentiodynamic polarization tests.