Corrosion inhibition by leaves and stem extracts of Sida acuta for mild steel in 1 M H2SO4 solutions investigated by chemical and spectroscopic techniques

Corrosion inhibition of mild steel in 1 M H2SO4 by leaves and stem extracts of Sida acuta was studied using chemical (weight loss and hydrogen evolution) and spectroscopic (AAS, FTIR and UV-V) techniques at 30–60 °C. It was found that the leaves and stem extracts of S. acuta inhibited the acid induced corrosion of mild steel. The inhibition efficiency increases with increase in concentration of the extracts but decrease with rise in temperature. Inhibitive effect was afforded by adsorption of the extracts’ components which was approximated by Freundlich adsorption isotherm. Inhibition mechanism is deduced from the temperature dependence of the inhibition efficiency and also from spectroscopic results.