Inhibition Behavior of 4-Aminoantipyrine on Carbon Steel in HCl Solution

The inhibition behavior of 4-Aminoantipyrine on carbon steel in HCl solution was studied by weight loss testing, potentiodynamic polarization curvers and electrochemical impedance spectroscopy. The results show that the inhibition efficiency increased with the increase of 4-Aminoantipyrine concentration. 4-Aminoantipyrine is a mix-type inhibitor which can inhibit the reaction of anode and cathode, and the standard free Gibbs energy of adsorption is -30.52 kJ·mol-1, which indicates that 4-Aminoantipyrine can adhere on carbon steel surface with a kind of spontaneous adsorption model between physical adsorption and chemical adsorption, and obeys Langmuir isotherm.