Department of Chemical, Metallurgical and Material Engineering, Tshwane University of Technology, Pretoria, South Africa
Popoola, A.P.I., Department of Chemical, Metallurgical and Material Engineering, Tshwane University of Technology, Pretoria, South Africa; Fayomi, O.S.I., Department of Chemical, Metallurgical and Material Engineering, Tshwane University of Technology, Pretoria, South Africa; Adeleke, A.A., Department of Chemical, Metallurgical and Material Engineering, Tshwane University of Technology, Pretoria, South Africa
The effect of Persea Americana (PA) hexane juice extract on the corrosion behavior of aluminium in 1M H2SO4 contaminated with 3.65% NaCl (acid-chloride) has been studied by linear potentiodynamic polarization and gravimetric measurements. The morphological behavior and the degradation process at the interface were examined with OPM and SEM/EDX analysis. The results obtained indicated that inhibition efficiency generally decreased with the increase in test duration and that increase in percent inhibitor caused alternating increase and decrease in the corrosion rate. This alternating decrease and increase may be due to the deposition of corrosion products in the contaminated solution and on the surface of the specimen which might be an indication of the impotency of the inhibitor to maintain a cohesive, stable oxide film on the aluminium surface in the presence of acid-chloride ions. The Tafel parameters of inhibition efficiency, corrosion current density and anodic and cathodic constants showed that the PA inhibitor only works effectively at a higher PA while below this; there is dramatic acceleration of corrosion rate of Aluminium in the simulated acid-chloride environment instead of reducing it. It is recommended that PA use as an inhibitor be further examined under other corrosive simulated environments or rather be used at higher concentration.