Leave extract of syzygium malaccenseas green inhibitor of mild steel in acidic medium

Abstract

Corrosion inhibition of mild steel in 1N hydrochloric acid medium was investigated in the presence of Syzygium malaccense leaves extract (SMLE) as a green corrosion inhibitor. The inhibition effect of the extract was studied by weight-loss method, potentiodynamic polarization, Fourier transform infrared spectroscopy, x-ray diffraction and scanning electron microscopy. The inhibition efficiency increased with increasing inhibitor concentration and temperature. The temperature effect on inhibition process in 1N hydrochloric acid solution at temperature range 303 – 333 K. The results showed that the highest inhibition efficiency 88.11% was observed in the presence of 7 g/L SMLE in 1N hydrochloric acid solution at high temperature. The adsorption of SMLE was found to obey the Langmuir adsorption isotherm model. A mixed-type inhibitor of SMLE was confirmed from the potentiodynamic polarization. Thermodynamic and kinetic parameters were assessed on the corrosion and inhibition process.