Emilia Sonchifolia Extract as Green Corrosion Inhibitor for Mild Steel in Acid Medium using Weight Loss Method

The effect of naturally occurring Emilia Sonchifolia (ES) was investigated as corrosion inhibitor for mild steel in 1.0M H2SO4 using gravimetric measurement at 30oC and 60oC. The extract was found to retard corrosion rate of Mild steel. The inhibition efficiency (IE %) increased with increase in concentration of the ES extract up to 74.77% at 1.0 M. Increase in temperature increased the corrosion rate in the absence and presence of inhibitor but decreased the inhibition efficiency. ES was found to obey Langmuir adsorption isotherm and Kinetic-Thermodynamic Model of El-Awady et al. at all the concentrations and temperatures studied. Phenomenon of physical adsorption is proposed from the activation parameters obtained. Thermodynamic parameters reveal that the adsorption process is spontaneous. Keywords: Emilia sonchifolia, corrosion, inhibitors, mild steel, acid, weight los