Corrosion inhibition of carbon steel by malva Sylvestris leaves extract in saline solution.

Abstract

Researchers used scanning electron microscopy (SEM) as well as potentiodynamic polarization to examine the effectiveness of an extract from Malva Sylvestris (MS) leaves in inhibiting the corrosion of a low-carbon steel saline solution (0.6 M NaCl). The test extract significantly reduced the corrosion rate of carbon steel in a saltwater environment. With 800 ppm of drug on a carbon steel surface, the malva leaf extract exhibited an 86.5% inhibition efficiency; this efficiency rose with increasing inhibitor concentration but fell with rising temperature. Adsorbing MS  molecules onto a metal surface stands for a mechanism by which inhibition occurs, according to the results, which followed the Langmuir adsorption isotherm. In order to explain how corrosion inhibition works, certain thermodynamic parameters ∆G_ads and activation energy (E_a) were determined. Extract from malva sylvestris leaves was found to be of mixed type according to the polarization measurements. Using SEM, we compared the surface properties of inhibited and uninhibited metal samples.