Electrochemical and quantum chemical studies of N,N′-bis(4-hydroxybenzaldehyde)-2,2-dimethylpropandiimine Schiff base as corrosion inhibitor for low carbon steel in HCl solution

Abstract

A synthesized Schiff base N,N'-bis(4-hydroxybenzaldehyde)-2,2-dimethylpropandiimine (p-HBDP) was studied as green inhibitor for the corrosion of low carbon steel in 1 M HCl solution using electrochemical, surface and quantum chemical methods. Results showed that the inhibition occurs through the adsorption of the inhibitor molecules on the metal surface. The inhibition efficiency was found to increase with increasing inhibitor concentration and de-creased with increasing temper-ature, which is due to the fact that the rate of corrosion of steel is higher than the rate of adsorption. Thermodynamic parameters for adsorp-tion and activation processes were determined. Polarization data indicated that this compound act as mixed-type inhibitors and the adsorption isotherm basically obeys the Langmuir adsorption isotherm. The calculations of reactivity indices of p-HBDP such as softness and natural charge distributions together with local reactivity by means of Fukui indices were used to explain the electron transfer mechanism between the p-HBDP molecules and the steel surface.

Corrosion inhibition studies of N,N′-bis(4-formylphenol)-1,2-Diaminocyclohexane on steel in 1 HCl solution acid

“…Fitting of experimental impedance spectroscopy data to the proposed equivalent circuit was done by home written the least square software based on the Marquardt method for the optimization of functions and Macdonald weighting for the real and imaginary parts of the impedance [20,21] .…”

“…Generally, the essential step in an inhibition mechanism is the adsorption of inhibitor on the steel surface [21] ; therefore, the increase in corrosion inhibition is caused by the adsorption of inhibitors on the steel surface. To describe the adsorption of 4-HCD on the steel surface, several adsorption isotherms were tested, including Freundlich, Temkin, Frumkin, Bockris-Swinkels, FloryHuggins and Langmuir isotherms [ [38][39][40] ].…”

Practical and Theoretical Study on the Inhibitory Influences of New Azomethine Derivatives Containing an 8-Hydroxyquinoline Moiety for the Corrosion of Carbon Steel in 1 M HCl

“…Our circuit comprising the following elements: the solution resistance (Rs), which is in series with a constant phase element (CPE) that is in parallel with the polarization resistance (Rp). So, the CPE defined the quasi-capacitive behaviour of the adsorbed chemical species in the electrical double layer and its use shows an improvement in fit in relation to the capacitance 49 . It is expressed by the next formula: (15) Where A is a constant of CPE in (Ω -1 s n cm -2 ), n is a limited number from 0 to 1 identifying the phase shift and ω is a angular frequency in (rad s -1 ) which is calculated as the product of 2π and the frequency.…”

The Effect of Immersion Time and Immersion Temperature on the Corrosion Behavior of Zinc Phosphate Conversion Coatings on Carbon Steel

“…The economic consequences of corrosion of iron and its alloys in various industrial sectors, including oil and gas operations, are investigated 3 . There are different ways to control corrosion including inhibitors, coatings, applying anodic/cathodic protection and proper design 4 . Surface treatment is an effective technique to solve the problem, which includes chemical conversion coating, [5][6][7][8][9] electroplating and electroless plating, 10,11 physical vapor deposition 12,13 and so on.…”