Response Surface Optimization of the Inhibition Efficiency of Gongronema latifolium as an Inhibitor for Aluminum Corrosion in HCl Solutions

摘要

The inhibiting effects of Gongronemalatifolium on corrosion of aluminum in 0.5M and 2M HCl solution was investigated using gravimetric technique at temperatures of 303K and 333K. The results indicated that the extracts inhibited the corrosion process in the acid media and inhibition efficiency improved with inhibitor concentration but decreased with increase in temperature which suggests a physical adsorption. The analysis of the results showed that the linear and quadratic effects of the process variables were highly significant, as well as, the interaction effect of temperature and time. The optimum conditions obtained were, Acid Concentration 1.73mol/l; Temperature 328.62 K; Time 10.14 hours; Extract Concentration 1000mg/L; and the Optimum Inhibition Efficiency at this optimum condition was predicted to be 74.14%. Gravimetric experiments were carried out at these optimum conditions to validate the predicted optimum values. The obtained experimental value of 75.43% agreed closely with that obtained from the regression model. This study has revealed that Gongronemalatifolium (GL) extract is a good inhibitor for the corrosion of aluminum in HCl solution and the performance can be improved by carefully moderating the process parameters.