Inhibition of mild steel corrosion in acidic medium using theobroma cacao pod
Date
2020-03
Journal Title
Journal ISSN
Volume Title
Publisher
UP
Abstract
Corrosion inhibition effect of cold water extract of Theobroma cacao pods - Cocoa pod (TCP-CP) on mild steel corrosion in 1 M HCl base stock solution has been studied. The study was conducted using weight loss measurement narrowed down to the effect of immersion time, inhibitor concentration and temperature on the corrosion behavior of mild steel in 1 M HCl in the absence and presence of TCP-CP. The study also investigated the thermodynamic properties of the inhibitor in the corrodent and revealed that the adsorption of the cold extracts of TCP-CP on mild steel surface was concentration dependent and obeyed Langmuir adsorption isotherm. The equilibrium constant of adsorption process (Kads) for TCP-CP inhibitor evaluated mathematically is 0.00266, 0.0271, 0.1795, 0.0253 and 0.0147 (mg/L) with a free energy of adsorption (∆Goads) value of -0.978, -1.060, -6.173, 0.942 and 0.737 kJ/mol at 303, 313, 323, 333 and 343 K respectively. The small values of Kads suggest weak absorption which is corroborated by the low negative values of the free energy of adsorption, ∆Goads, values obtained from thermodynamic measurements. The negative value of ∆Goads suggests that the adsorption of TCP-CP inhibiting particles on the mild steel surface was favourable from thermodynamic point of view and provided proof that TCP-CP extracted with cold water is an efficient inhibitor and the thermodynamic properties of the examined concentrations determined
Description
This research was conducted in collaboration with a staff of this institution
Keywords
Mild Steel, corrosion inhibition, theobroma cacao pods husks, thermodynamic properties, weight loss, aqueous extract, plant extract, Department of Chemical Engineering
Citation
Izionworu, V. O., Ukpaka, C. P. & Oguzie, E. E. (2020). Inhibition of mild steel corrosion in acidic medium using the obroma cacao pod. International Journal of Scientific & Engineering Research, 11(3), 255 – 265