An investigation of mild steel corrosion inhibition in hydrochloric acid medium by environment friendly green inhibitor

The inhibitive effect of Thymus algeriensis plant extract (TEA) on the corrosion of mild steel in 1.0 M HCl solution has been investigated by weight loss measurement as well as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The presence of Thymus algeriensis plant extract reduces remarkably the corrosion rate of mild steel in acidic solution. The effect of temperature on the corrosion behavior of mild steel was studied in the range of 313-343 K. The results from this corrosion test clearly reveal that the extract behaves as a mixed type corrosion inhibitor with the highest inhibition at 1.0 g/L. The Nyquist plots showed that increasing TEA concentration, charge-transfer resistance increased and double-layer capacitance decreased, involving increased inhibition efficiency. Linearity of Temkin isotherm adsorption.