Adsorption Effect of Five‐Membered and Six‐Membered Alicyclic Amine‐Derived Mannich Bases on Mild Steel Surface in 1.0 M HCl

Abstract

Two new Mannich bases N‐(3‐(benzo[d][1, 3]dioxol‐5‐yl(pyrrolidin‐1‐yl)methyl)‐4‐hydroxyphenyl)acetamide (I1) and N‐(3‐(benzo[d][1, 3]dioxol‐5‐yl(morpholino)methyl)‐4‐hydroxyphenyl) acetamide (I2) are synthesised and evaluated their corrosion inhibition behaviour through weight loss measurements, electrochemical, quantum chemical and surface analytical studies. Tafel studies revealed that the inhibitors are found to be mixed type. EIS studies confirmed that corrosion process is controlled through charge transfer process. The adsorption of inhibitors I1 and I2 follows Langmuir adsorption isotherm and ΔGads values suggest that both physorption and chemisorption are possible. Surface studies show that in the presence of inhibitors, smoother surface is obtained compared to blank. I1 has higher inhibition efficiency (50 μM −98%) than I2 (50 μM −94%) which is correlated with the theoretical studies.

Schiff Bases of 2,5‐Thiophenedicarboxaldehyde as Corrosion Inhibitor for Stainless Steel under Acidic Medium: Experimental, Quantum Chemical and Surface Studies

“…The investigated molecules SS1 & SS2 differ from one another by the presence of hetero atoms, which change the properties of molecules . Table shows calculated electronic properties like I , A , Δ E , μ, Χ , η and Δ N of SS1 & SS2 in gas phase and aqueous medium . The trend of values observed for studied inhibitor molecules are well in agreement with their experimentally measured inhibition efficiency.…”