# Study of Extracts of A. rusticana as Corrosion Inhibitors of Mild Steel in 1 mol L–1 HCl Solution Using MALDI-TOF-MS

## TL;DR

This study shows that extracts from A. rusticana can effectively inhibit corrosion of mild steel in acidic conditions, with glucosinolates being the likely active compounds.

## Contribution

The study identifies glucosinolates as key corrosion inhibitors in A. rusticana extracts using advanced analytical techniques.

## Key findings

- The ethyl acetate fraction of A. rusticana extract achieved over 96% corrosion inhibition efficiency.
- Glucosinolates were identified as the major component remaining on the metal surface after washing.
- Corrosion inhibition was confirmed through mass loss, electrochemical, and surface analysis methods.

## Abstract

Corrosion studies were performed using extracts of Armoracia rusticana and their fractions through mass
loss measurements, electrochemical impedance, and potentiodynamic
polarization at concentrations of 100, 200, 400, 800, 1600, and 3200
mg L–1 in 1 mol L–1 HCl. The Fourier
transform infrared, ESI-MS(±), MALDI-FT-ICR(±), and MALDI-TOF(±)
techniques were used for the chemical characterization of the extracts
and their fractions. The ethyl acetate fraction of the crude ethanolic
extract (WEP-EtOAc) showed the highest inhibition efficiency, above
96%, verified by mass loss measurement with and without temperature
variation and electrochemical tests. Scanning electron microscopy
and X-ray photoelectron spectroscopy analyses were performed for the
surface analysis. MALDI-TOF was also used for the ethyl acetate fraction
of WEP, where the laser was applied directly to the metal plate under
study. Even after washing, the glucosinolate chemical group was identified
as the major component on the metal surface. This study suggests that
glucosinolates are the possible main corrosion-inhibiting phytochemicals
in the extract.