Time and temperature elucidation on steel corrosion inhibition by 3-methyl-1-prop-2-ynylquinoxalin-2(1H)-one in molar hydrochloric Acid: Part 2

The corrosion rate in the presence of a new synthesized quinoxaline derivative namely 3-methyl-1-prop-2-ynylquinoxalin-2(1h)-one and denoted pr-n-q=o as mild steel corrosion inhibitor in molar hydrochloric acid,was studied by weight loss method,in the range of temperature from 308 to 353 k. results obtained revealed that the inhibition efficiency of this compound decreased relatively with increasing temperature and its value reached 80.0% at 353 k at 10-3m. the inhibition was assumed to occur via adsorption of the quinoxaline molecules on metallic surface. adsorption of pr-n-q=o obeyed to langmuir adsorption isotherm model fit. the apparent activation energies ea,enthalpy δh* and entropy of activation δs* values provided evidence of the inhibitory effect of pr-n-q=o. furthermore,spontaneity of the adsorption process,through free energy δadsgdeg; values showed a drastic decrease upon temperature increase in the presence pr-n-q=o.