Experimental and theoretical investigation of inhibition behavior of bisflavanol for Q235 steel in hydrochloric acid solution

Bis-8,8'-catechinylmethane, known as bisflavanol (BF), from cacao liquor was synthesized here as effective, eco-friendly, especially edible corrosion inhibitor for Q235 steel in HCl. The result of gravimetric measurements showed that the inhibition efficiency of BF at 0.1 mM was 92.42%, while catechin at 0.2 mM was 78.28%, reflecting a synergistic effect between the two catechin moieties of BF. Activation parameters Delta G0 ads, E-a, Delta H* and Delta S* were evaluated and discussed. Surface morphological analyses (SEM, EDX and AFM) showed that a film of inhibitor was formed on the surface of Q235 steel. XPS, Fukui function and MD simulations were used to study the corrosion inhibition performance of FP in HCl, predict the interaction between FP and Q235 steel, and verify the experimental results. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

BF synthesized from cacao liquor was found to be an effective corrosion inhibitor for Q235 steel in HCl, with a high inhibition efficiency and synergistic effect between the two catechin moieties. Various characterization techniques and computational methods were used to validate the corrosion inhibition performance of BF and verify the experimental results.