TITLE:
Unification of the Quadratic Model Equations of the Inhibition Characteristics of Acidified Ocimum Basilicum on the Corrosion Behaviour of Mild Steel
AUTHORS:
Michael O. Nwankwo, Paul A. Nwobasi, Peter O. Offor, Ndubuisi E. Idenyi
KEYWORDS:
Corrosion; Inhibition; Ocimum Basilicum; Correlation; Quadratic Models; Passivation
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.1 No.6,
November
27,
2013
ABSTRACT: An attempt has been made at unifying the resulting quadratic models from the study of the correlation behavior of the inhibition characteristics of acidified ocimum basilicum on conventional mild steel. Weight-loss corrosion technique was employed in obtaining the corrosion penetration rate using the equation: cpr = . Subsequently, the quadratic models were developed by using a computer-aided statistical modeling technique (International Business Machine (IBM)’s SPSS version 17.0). The results obtained showed a nearly perfect positive correlation with a correlation coefficient in the range of 0.986 ≤ R ≤ 0.996 which depicts that R ≥ 1. Also, the coefficient of determination fell within the range of 0.972 ≤ R2 ≤ 0.992 showing that approximately 97% to 99% of the total variation in passivation rate was accounted for by corresponding variation in exposure time, leaving out only between 3% and 1% to extraneous factors that are not incorporated into the model equations. The equations were further unified into a generalized form using MathCAD 7.0 and the resulting equation was y = 1.032 － 0.002t + 1.899× 10-6t2 with a R2 value of 0.935 indicating a well-correlated relationship. With this, a new frontier on corrosion studies has emerged typifying a classical departure from previously long-held assumption that corrosion behaviours at room temperature were only logarithmic.