Synthesis, characterization of some azo dyes derived from sulfa drugs and the use of them as corrosion inhibitors in 0.5m hydrochloric acid solution

Abstract EN

-Three azo dyes derived from sulfa drugs and pyridoxal were synthesized.

The prepared compounds were identified by CHNS analysis FT-IR and P1PH-NMR spectroscopy.

The prepared azo dyes were studied as corrosion inhibitors in 0.5M HCl solution by the weight loss and galvanostatic polarization techniques in the range of temperature 30, 40, 50 and 60PoPC.

the results obtained revealed that A2 performed excellently as a corrosion inhibitor for C-steel in hydrochloric acid media and its efficiency attains 80% at 5x10P-3PM, time of 5hr and at 30PoPC.

The efficiency of inhibitors was decreased as the temperature increases.

The effect of temperature on the rate of corrosion in the absence and presence of these compounds was also studied.

The Langmuir adsorption isotherm was tested for their fit to the experimental data.

The apparent activation energies, Arrhenius constant, enthalpies and entropies of the dissolution process and the free energies and adsorption equilibrium constant for the adsorption process were determined and discussed.

The fundamental thermodynamic functions were used to glean important information about A1, A2 and A3 inhibitory behavior.