Experimental and theoretical studies of 5-((4-phenyl-4,5-dihydro- 1H-tetrazol-1-yl)methyl)quinolin-8-ol quinoline derivative as effective corrosion inhibitor for mild steel in 1.0 M HCl

Abstract

A new organic inhibitor, namely 5-((4-phenyl-4,5-dihydro-1H-tetrazol-1- yl)methyl)quinolin-8-ol, denoted PTQ8 was synthesized and characterized using 1H and 13C NMR spectroscopies. Thus, its corrosion inhibition on mild steel in 1.0 M HCl solution was investigated by weight loss and electrochemical measurements. The experimental results were supported by DFT calculations. The temperature effect on the corrosion behaviour of mild steel in 1.0 M HCl without and with PTQ8 was studied in the temperature range 298-328 K. The results showed that the inhibition efficiency of PTQ8 increases with concentration and decreases with temperatures. The associated activation energy has been determined and discussed. It is found that the adsorption of PTQ8 on the mild steel surface obeys to the Langmuir's adsorption isotherm. It is found also that the theoretical calculations are in good agreement with the experiments results.