Research of Lilium brownii leaves extract as a commendable and green inhibitor for X70 steel corrosion in hydrochloric acid

Here, to restrain the corrosion of X70 steel in the pickling process (1 M HCl solution), an extract of Lilium brownii leaves is developed to boost the corrosion inhibition performance via a facile pure water extraction method. The extract of Lilium brownii leaves exhibits a corrosion efficiency of about 85% at 200 mg/L at all tested temperatures of 298 K, 303 K, and 308 K, which reveals that the developed extract significantly restrains the corrosion of X70 steel. Further, its corrosion inhibition mechanism, especially the adsorption model, the relationship of structure-function, and the adsorption configuration, is elucidated. A comprehensive study suggests that the extract is a mixed-type corrosion inhibitor with physical and chemical adsorption, consisting with Langmuir adsorption model. Particularly, quantum chemistry and molecular dynamics calculations are performed for the four main molecules in the developed extract to further reveal the adsorption mechanism. Meanwhile, this work can enlighten and promote the development of a high-performance green inhibitor in future applications of pickling solutions. (C) 2020 Elsevier B.V. All rights reserved