CORROSION INHIBITION BEHAVIOUR OF WATER HYACINTH EXTRACT ON ALUMINIUM, COPPER, AND GREY CAST IRON ALLOYS

Abstract

Radiators in cars are normally made of metals and special composites which all have the tendency to corrode. The inhibition of the corrosion of Copper, Cast iron, Aluminium alloys using Water Hyacinth leaves extract has been studied using weight loss. Weight loss of the metal coupon was reduced by the extract and 20g of extract works better for the Aluminium alloy while 30g of extract works better for Cast Iron and Copper alloy.Inhibition was found to increase with Water hyacinth extract. The Electrode potential tends to be positive while the pH is not acidic and this shows that inhibition is perfectly in place.The effect of temperature and immersion time, on the corrosion behaviour with addition of Water hyacinth extract was also studied. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the metal surface. The protective film formed on the metal surface was analyzed by Fourier transform infra-red spectroscopy (FTIR). The results obtained showed that the extract could serve as an effective inhibitor. The use of the preservative would increase the shelf life of the extract. The use of sodium benzoate as preservative on the extract also serves as an inhibitor. This further signifies its effectiveness as a preservative and also an inhibitor.