Abstract
We have isolated three pyridine base alkaloids namely ricinine (C1),N-demethylricinine (C2) and 4-methoxy pyridine-3-carboxylic acid (C3) from methanolic extract ofRiccinus Communisleaves and investigated corrosion inhibition effect on mild steel in 0.5 HCl solution using the weight loss and electrochemical techniques (Galvanostatic polarization and EIS). Polarization resistances calculated from the EIS measurements are in good agreement with those obtained from alternating current (AC) polarization measurements. The mild steel samples were also analyzed by Scanning Electron Microscopy (SEM). The results show thatC1is an excellent inhibitor for mild steel in acid medium. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the metal surface. In the 298- 308 K temperature range, theC1,C2andC3adsorption follows Langmuir isotherm model. The protection efficiency increases with increasing the inhibitor concentration in the range of 250-1000 ppm but slightly decreases with increasing temperature.
Highlights
Pure metal and alloys react chemically / electrochemically with corrosive medium to form a stable compound, in which the loss of metal occurs
This study reveals the possibility of the adsorption on the inhibitor on the metal surface
The maximum inhibition was obtained for the inhibitor concentration of 1000 ppm for each inhibitor at the testing temperatures
Summary
Pure metal and alloys react chemically / electrochemically with corrosive medium to form a stable compound, in which the loss of metal occurs. Corrosion Inhibition of Mild Steel in HCl S321 and reference electrode respectively.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
