Study on Synergistic Corrosion Inhibition Effect between Calcium Lignosulfonate (CLS) and Inorganic Inhibitors on Q235 Carbon Steel in Alkaline Environment with Cl−

Abstract

The synergistic corrosion inhibition effect between calcium lignosulfonate (CLS) and three kinds of inorganic inhibitors (Na2MoO4, Na2SnO3, and NaWO4) with various molar ratios on Q235 carbon steel in alkaline solution (pH 11.5) with 0.02 mol/L NaCl was investigated by cyclic potentiodynamic polarization, electrochemical impedance spectroscopy, linear polarization, scanning electron microscopy, and X-ray photoelectron spectroscopy. Molybdate and stannate in hybrid inhibitor could promote the passivation of steel and form a complex film, which could suppress the corrosion effectively. Moreover, the insoluble metal oxides in the complex film formed by three kinds of inorganic inhibitor could help the adsorption of CLS onto the steel surface. The CLS molecules could adsorb onto the steel surface and metal oxides to form an adsorption film to protect the steel from corrosion. A three-layer protection film formed by a hybrid inhibitor, including passivation film, deposition film, and adsorption film, would effectively inhibit the corrosion reactions on the steel surface. The CLS compound with molybdate with the ratio of 2:3 shows the best inhibition effect on both general corrosion and localized corrosion.

Experimental and Theoretical Studies on Extract of Date Palm Seed as a Green Anti-Corrosion Agent in Hydrochloric Acid Solution

“…Green inhibitors are non-toxic, natural, friendly to the environment, and renewable. These compounds generally contain nitrogen, sulphur, and oxygen and can be extracted inexpensively from plant parts such as leaves, seeds, flowers, and fruits using simple methods [5,6]. The effectivity of these inhibitors depends on their electronic structures, electron density at the donor sites, aromaticity, molecular area, type of corrosive media, and temperature.…”

Na2SnO3 functions as outstanding magnesium alloy passivator by synergistic effect with trace carboxymethyl chitosan for Mg–air batteries for standby protection

“…8 Inorganic inhibitors can promote the passivation of the metal surface to form metal oxides and the reduction products of inorganic inhibitors; in chloride-enriched media, such inhibitors have a better effect on the inhibition of the initiation of pitting corrosion, and can also promote the re-passivation of the metal surface. 9,10 Common organic corrosion inhibitors include organic amines, aldehydes, heterocyclic compounds, imidazolines, and their derivatives. The majority of these are obtained using diverse chemical reagents under different synthetic conditions, which leads to the prohibitively high cost of organic corrosion inhibitor production, thus limiting their industrial applications.…”

Synthesis and Structure of Water-Soluble Sb Quantum Dots and Enhanced Corrosion Inhibition Performance and Mechanisms

“…18,19 On the other hand, the inorganic inhibitors such as Na 2 MoO 4 and ZnO could also inhibit mild steel corrosion and prolong its service life. 20,21 The corrosion inhibition efficiency of the inorganic corrosion inhibitors relied on the passivation of steel and formed a complex film, which could effectively retard corrosion.…”

“…Both organic and inorganic corrosion inhibitors play an important role in inhibiting corrosion in corrosive environments. On the one hand, the organic inhibitors effectively prohibited Q235 steel corrosion and further promoted its service life. − The corrosion inhibition efficiency of these organic corrosion inhibitors mainly depended on the active sites that determined the adsorption capability of corrosion inhibition molecules onto the metal substrate, for instance, π bonds, heteroatoms (S, N, and O), and polar functional groups. − The corrosion inhibition molecules could adsorb on the metal surface through covalent bonds or electrostatic interaction, forming an adsorption film, which could shield the metal surface from the attack of corrosive media. , On the other hand, the inorganic inhibitors such as Na 2 MoO 4 and ZnO could also inhibit mild steel corrosion and prolong its service life. , The corrosion inhibition efficiency of the inorganic corrosion inhibitors relied on the passivation of steel and formed a complex film, which could effectively retard corrosion.…”