Evaluation of the Electrochemical Impedance Measurement of Mild Steel Corrosion in an Acidic Medium, in the Presence of Quaternary Ammonium Bromides

Abstract

Three quaternary ammonium bromides were investigated as mild steel corrosion inhibitors in 1 M HCl. Two investigation methods were applied: electrochemical impedance spectroscopy (EIS) and polarization resistance (Rp method). The experimental impedance data showed capacitance frequency distribution, which imposed the introduction of a constant phase element, instead of a pure capacitance. Adequate structural models were advanced, to describe the interfacial processes. The models parameters values were determined. The resistance values found by impedance spectroscopy were compared to those of the polarization resistance provided by the Rp method. The inhibition efficiency of the investigated compounds was evaluated by both applied methods. The comparison of the investigated compounds' protective properties outlined the best among them.

A Synergistic Effect between Stearic Acid and (+)-α-Tocopherol as a Green Inhibitor on Ferritic Stainless Steel Corrosion Inhibition in 3.0% NaCl Solution

“…and is an integral part of the parameter CPE, which must be taken into account when calculating the capacity of pores, surface layers or the double layer. according to Equation ( 6) [83][84][85].…”

Temperature Effect on the Corrosion Inhibition of Carbon Steel by Polymeric Ionic Liquids in Acid Medium

“…In the interfacial phenomena controlled by diffusion, relaxation processes occur at specific frequencies and temperatures; in an electrochemical system, the characteristic constant of such a process within the time domain is known as the relaxation time ( τ dl ), which is defined as the time necessary for the charge distribution to recover the equilibrium state and is commonly employed to distinguish the polarization effects that normally overlap in the frequency domain and that can be attributed to underlying physical processes [ 44 , 45 ]. The relaxation time ( τ dl ) is given by Equation (3) [ 46 , 47 ]: …”

Systematic investigation of the adsorption and inhibition properties of a new clickable 1,2,3‐triazole compound for mild steel in 1 M HCl medium

“…The relaxation time (τ) that measures the time required to return to the equilibrium state after an electrical disturbance has calculated by the following formula: [60,61] t ¼ C dl � R ct (6) where C dl is the capacitance of the double layer, and R ct is the charge transfer resistance. Indeed, once NTM is added, the values of τ increase and those of C dl decrease (Tables 3 and 4), suggesting that the discharge and charge rates at the mild steel/solution interface have been significantly reduced.…”