Evaluation of Corrosion Inhibition of Mild Steel in 1 M Hydrochloric Acid Solution byMollugo cerviana

Abstract

The inhibiting effect of methanolic extract ofMollugo cervianaplant on the corrosion of mild steel in 1 M HCl solution has been investigated by different techniques like potentiodynamic polarization, electrochemical impedance spectroscopy, and weight loss methods for five different concentrations of plant extract ranging from 25 to 1000 mg/L. The results indicated that the corrosion inhibition efficiency increased on increasing plant extract concentration till 500 mg/L and decreased on further increasing concentration. The extract was a mixed type inhibitor with the optimum inhibition concentration of 500 mg/L in potentiodynamic polarization. The adsorption of the plant extract on the mild steel surface was found to obey Langmuir adsorption isotherm. Surface analysis was also carried out to find out the surface morphology of the mild steel in the presence and in the absence of the inhibitor to find out its efficiency. The obtained results showed that theMollugo cervianaextract acts as a good inhibitor for the corrosion of mild steel in 1 M HCl solution.

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

“…Therefore, electrons must transfer from HOMO or HOMO-1 to metal surface. As results, N 2 atom is the most active site for inhibitor ( 1 ) and any nitrogen atoms are the most active site for inhibitor ( 2 ).…”

“…Some structural parameters of investigated inhibitors are listed in Table 6 for non-protonated and protonated form. According to Table 6 , N2 -H length of protonated inhibitor ( 1 ) is shorter than protonated inhibitor ( 2 ). Structural changes between non-protonated and protonated forms are occur around N 2 atoms.…”

“…Steel in acidic solution is widely used in various industrial processes, due to the general aggressive nature of acid solutions, this leads to corrosive attack [2] . Massive costs are invested to manage corrosion in the oil and gas industry.…”

Effect of Equisetum arvense extract as corrosion inhibitor of A36 steel in sulfuric acid solution

“…The CPE allows to get a more accurate fit of experimental data set and its impedance is given by Eq. : where A is proportionality coefficient, ω is the angular frequency, and i is the imaginary number, n is an exponent related to the phase shift and can be used as a measure of surface irregularity . The value of C dl , can be calculated for a parallel circuit composed of a CPE ( Q ) and R ct , according to the following equation: …”

Mangrove bark tannins as a Zn–P coating sealant for mild steel corrosion protection in 3.5% NaCl solution

“…Moreover, as the concentration of tannin increased, the inhibition efficiency increased until it reached the optimum concentration. This is due to the adsorption of inhibitor in the plant extract on the mild steel surface [23] and formed strength inhibitive film [24]. For both TAE and TME, the highest inhibition efficiency was at 4 g l −1 tannin Zn-P coated mild steel that were 71.12% and 83.52% respectively and it was at the optimum.…”