Experimental and Computational Studies of Some Drugs as Corrosion Inhibitors for Aluminium and Some Its Alloys in Saline solution

This thesis involves the investigation of the corrosion behaviour of pure aluminium as well as of two of aluminium – base alloys (5052Al and 2024Al)in sodium chloride solution over a temperature range (283 – 323 K) with and without ampicillin (AMP.), cephalexin (CEX.) and amoxicillin (AMOX.) as inhibitors. The results of  electrochemical experimental study revealed that:
1. The current density increases with increasing temperature in the range of  (283-323) K.
2. The inhibition efficiency increases with increasing the concentration of inhibitors (AMP., CEX., and AMOX.), this means that these inhibitors act as an adsorption inhibitors on the surface for the corrosion of pure Al, 5052 Al, and 2024 Al in 3.5% NaCl.
3. The inhibition efficiency of AMP., CEX., and AMOX. decreases with increasing temperature from 283 to 323 K.
4. According to the corrosion potential, AMP., CEX., and AMOX. act as mixed type inhibitors since corrosion potential does not change approximately in NaCl solution.
5. The thermodynamic parameters  of corrosion ΔH, ΔG, and ΔS have been calculated at different inhibitors concentrations and temperatures.The values of ΔG and ΔH indicate the spontaneous and exothermic
corrosion processes respectivelly.