Inhibition of mild steel corrosion in sulfuric acid solution using collagen

Inhibitive effect of collagen on the acid corrosion of mild steel in 0.5 M H2SO4 solution was studied by electrochemical impedance spectroscopy and electrochemical frequency modulation. Collagen effectively inhibited the corrosion of mild steel with efficiency ranges from 88.9 to 96.5 % for collagen concentrations from 20 to 80 ppm. Adsorption isotherm study was performed using weight loss measurements where Langmuir and El-Awady models were applied on data to investigate the mode of adsorption. Corrosion inhibition was also tested at different temperatures to measure the thermodynamic parameters; Delta GA degrees, Delta HA degrees, Delta SA degrees and E (a). Inhibition is suggested to occur due to adsorption phenomenon and data obey the El-Awady model. Thermodynamic study reveals that adsorption is endothermic-physical process driven by entropic factors.