Browsing by Author "Bamgbose, Janet T."

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    Corrosion Inhibitive Effect of Ocimum Gratissimum Extract on Zinc-Aluminium Alloy in Hydrochloric Acid
    (Sociedade Portuguesa de Electroquímica, 2011-11) Nkiko, Mojisola O.; Bamgbose, Janet T.
    The inhibitive effect of Ocimum gratissimum by seed extract on the corrosion of zinc-aluminium (ZA) alloy in 2 M hydrochloric acid (HCl) solution has been studied using gravimetric methods. Inhibition increases with concentration of extract but decreases with temperature. This observation implies that Ocimum gratissimum seed extract is an effective and non toxic inhibitor of the corrosion of zinc-aluminium alloy. Adsorption of the extract on the surface obeyed the Freundlich adsorption isotherm. The calculated rate constant (k) shows a first order kinetics in the absence and presence of the inhibitor. The kinetic parameter B, measured for the reaction has a high negative value which implies that Ocimum gratissimum becomes more effective as the temperature increases. Synergistic effect of halide additives shows an increase in the efficiency of the extract. However synergism parameter shows that synergism of halide additives decreases with increased concentration of inhibitor.
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    Experimental and Quantum Chemical Studies of the Inhibition of Copper with Sodium Dodecyl Sulphate (SDS) in Acidic Medium
    (Scientific Research Publishing, 2018) Nkiko, Mojisola O.; Oluwabi, Abayomi; Ahmed, Sikiru A.; Bamgbose, Janet T.
    This work investigates the inhibitive properties of sodium dodecyl sulphate (SDS) on the corrosion of copper (Cu) in nitric acid using gasometric methods. The inhibition efficiency increases with time and concentration of SDS. The corrosion rate of copper decreases as concentration of SDS increases. Adsorption of the SDS on the surface obeyed the Langmuir adsorption isotherm. The high negative values of the kinetic parameter B suggest that the inhibitor’s effectiveness increases with temperature. The equilibrium constant and the free energy of adsorption of SDS to copper are negative and large. This observation implies that the adsorption mechanism maybe chemisorption. The quantum chemical calculation of copper dodecyl sulphate shows that the energy change in the HOMO-LUMO energy of the moiety is positive and small. This observation implies that the SDS is an efficient inhibitor. The high dipole moment obtained implies that corrosion inhibition of Cu is enhanced by adsorption of SDS and this observation correlates with the observed experimental inhibition efficiency