Der Pharma Chemica
Journal for Medicinal Chemistry, Pharmaceutical Chemistry, Pharmaceutical Sciences and Computational Chemistry


Adsorptive and thermodynamic properties of methanol extract of Toona sinensis leaves for the corrosion of mild steel in HCl medium

Author(s): Emriadi*, Adlis Santoni and Yeni Stiadi

The inhibition effect of Toona sinensis leaves extract (TSLE) on the corrosion of mild steel in HCl solution was studied by weight loss, Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) methods. The results show that TSLE is a good inhibitor in 1.0 M HCl, and the inhibition efficiency increases with increasing concentration of the extract and decreases with increasing temperature. Inhibitive effect was afforded by adsorption of the extract on steel surface, which was found to accord with Langmuir adsorption isotherm. Adsorption and activation parameters such as activation energy (Ea), enthalpy (DH), free Gibbs energy (DG), and entropy (DS)were evaluated on the corrosion and inhibition process.