Efficiency of Some Newly Synthesized Mannich Bases as Corrosion Inhibitor for Mild Steel in HNO3 solution

Weight loss and thermometric methods have been used to study the corrosion inhibition of mild steel in HNO3 solution by four newly synthesized Mannich bases viz 3-oxo-3-phenyl-N,N-dimethyl propanamine hydrochloride (MB1), 3,5-dioxo-5-phenyl-N,N-dimethyl pentanamine hydrochloride(MB2), 2,2- dimethyl-3-oxo-N, N dimethyl butanamine hydrochloride (MB3) and 3-oxo-N,N-dimethyl butanamine hydrochloride((MB4).Efficiency of inhibitor increases with increasing concentration of inhibitor whereas it decreases with increasing concentration of acid. Results of inhibition efficiencies obtained from both methods are in good agreement with each other.