Corrosion Inhibition of Mild Steel using Fig Leaves Extract in Hydrochloric Acid Solution

Abstract

The inhibition effect of Fig leaves extract on corrosion of mild steel in 2M acid solution was investigated using traditional weight loss measurements and various electrochemical techniques. Corrosion inhibition efficiency of Fig leaves extracts was evaluated using weight loss measurements for effect of various solution concentrations. In addition, electrochemical techniques were performed to evaluate both concentration and temperature changes of test solution. Nyquist plots showed that the higher the Fig leaves extract concentration, the higher the charge transfer resistance and the lower the value of the double layer capacitance. Both weight loss and electrochemical results showed similar trend indicating that Fig leaves extracts adsorption on mild steel followed the Langmuir adsorption isotherm at all test temperatures. The change in free energy and the activation energy values indicate that the adsorption is physical. Inhibition efficiency of as high as 87% were achieved for Fig leaves extract of above 200 ppm.