Spanish English Chinese

Corrosion of metals is primarily a result of battery reactions occurring on the metal surface. This is also the most important factor leading to corrosion.

corrosion inhibitor

The battery reaction includes an anode reaction and a cathode reaction. If the corrosion inhibitor can inhibit the reaction, the corrosion rate of the metal will slow down.

The corrosion inhibitor which can inhibit anodic reaction is called anode type corrosion inhibitor. The corrosion inhibitor which can inhibit cathode reaction is called cathode type corrosion inhibitor. The corrosion inhibitor which can inhibit the anode reaction and the cathode reaction is called a mixed type corrosion inhibitor.

Potassium dichromate, potassium chromate, sodium nitrite, sodium nitrate, potassium permanganate, phosphate, silicate, borate, carbonate, benzoate, and cinnamate, etc.

The effect of the anode type corrosion inhibitor on the anode process is as follows.

Form a thin oxide film on the metal surface to isolate the metal from the corrosive medium.

The metal ionization process is inhibited by characteristic adsorption.

Bring the metal electrode potential to the passivation potential.

Zinc sulfate, calcium bicarbonate, lime, polyphosphate, silicate, and organic phosphonate are all cathodic type inhibitors.

The cathode type corrosion inhibitor mainly achieves corrosion inhibition by the following effects.

Increase the overpotential of the cathodic reaction. Sometimes the anionic corrosion inhibitor inhibits the hydrogen ion discharge reaction by increasing the overpotential of the hydrogen ion discharge.

For example, alkaline corrosion inhibitors such as Na2C03 and triethanolamine can neutralize acidic substances in water. Reduce the hydrogen ion concentration and increase the hydrogen evolution overpotential. The reduction of hydrogen ions on the metal surface is hindered. Reduce corrosion.

Form a compound film on the metal surface. Such as low molecular organic amines and their derivatives in organic corrosion inhibitors. They all form a multi-molecular layer in the cathode region of the metal surface. This makes it difficult to achieve a depolarizing agent to the metal surface, which can reduce corrosion.

Absorb dissolved oxygen in the water. Reduce the concentration of the cathode reactant in the corrosion reaction. Thereby slowing down the corrosion of the metal.

Mixed inhibition inhibitors are mostly organic compounds. The reactive groups on the molecules of the organic corrosion inhibitor interact with the metal ions generated during the etching to form a precipitated film. The electrochemical process of suppressing the two poles is performed.

Propargyl alcohol has a good corrosion inhibition effect on iron in acidic aqueous solution. 8-hydroxyquinoline has a corrosion inhibition effect on aluminum corrosion in an alkaline medium.

This is because the corrosion inhibitor reacts with aluminum ions to form an insoluble polymer precipitation film. This film covers the aluminum surface. Thereby, corrosion of aluminum in an alkaline aqueous solution is inhibited. The inhibition of copper by benzotriazole is also considered to be the formation of an insoluble polymer precipitated film.

The effects of mixed corrosion inhibitors on the electrochemical process of corrosion are mainly as follows.

It reacts with the anode to form an insoluble material. These insoluble materials are closely deposited on the metal surface to act as a corrosion inhibitor. Corrosion inhibition of iron, magnesium, aluminum, etc. Phosphates belong to this type. Such as Na3P04 and Na2HP04

Form colloidal substance. Compounds capable of forming complex colloidal systems can be used as effective corrosion inhibitors. For example, Na2Si03 and the like.

Adsorption on the metal surface. The formation of the adsorption film achieves the purpose of corrosion inhibition. Gelatin, gum arabic, etc. can be adsorbed on the aluminum surface. Pyridine and organic amines can be adsorbed on the surface of magnesium and magnesium alloys. They all play a role in corrosion inhibition.

The above is a detailed Guide to Electrochemical Mechanism of Corrosion Inhibitors 2019. Please feel free to contact us if you have questions about water treatment chemicals. Our official website is www.irowater.com.

Leave a Reply

Your email address will not be published. Required fields are marked *

08Jun 2020

There are many polyaspartic acid manufacturers and suppliers on Google. Some of them are trading companies, and some are real manufacturers. They are also under the banner of manufacturers and have also done “factory field certification”. This is also the case in many B2B yellow pages. Therefore, the business license says that the manufacturer may […]

26May 2020

The basic types of papermaking fungicides are mainly divided into two categories: inorganic fungicides and organic fungicides. According to different action principles, inorganic fungicides can be divided into oxidized type and reduced type. The reducing bactericide has a bactericidal effect due to its reducibility. Such as sulfurous acid and its salts. Oxidizing fungicides use their […]

11Mar 2020

Abstract: Computational chemists have actually produced a unique, synthetic, three-stranded particle that operates just like a natural metalloenzyme, or an enzyme which contains metal ions. Enzymes are nature’s powerhouses. Discovered in the cells of all animals, plants, as well as every other living microorganism, they accelerate the chain reactions that activate countless organic functions– from […]

31Oct 2019

Benzotriazole Corrosion Inhibitor Analysis in the Action Mechanism Abstract: This post introduces the properties and mechanism of benzotriazole corrosion inhibitors. The synergistic action of benzotriazole and imidazole better illustrates the progress of the sustained release. Combined with the corrosion example of copper in sodium chloride solution to illustrate the corrosion inhibition of triazole compounds. Keywords: […]

17Sep 2019

Abstract: A water-soluble copolymer scale inhibitor was synthesized from acrylic acid (AA) and 2-acryloyl-2-methyl propane sulfonic acid (AMPS). The scale inhibition and dispersion properties of the copolymer were determined. The effects of monomer ratio, reaction temperature and molecular weight modifier on the scale inhibition performance of the copolymer were investigated. Keywords: sulfonic acid, copolymer, scale […]

09Sep 2019

This article describes the commonly used experimental methods for assessing the biodegradability of polyacrylic acid polymers. It is recommended to use the carbon dioxide (PCD), oxygen consumption (COD) and infrared spectroscopy images of biodegradation to comprehensively analyze the biodegradability of polyacrylic acid polymers. The volume of the bioreactor is 2L, the concentration of the tested […]

23Aug 2019

2-Hydroxyphosphonoacetic acid is a good scale inhibitor. Its appearance is a dark brown liquid with a molecular formula of C2H5O6P and a relative molecular mass of 156.03. The preparation method generally has the following three methods. Method One 16.3 parts (0.11 mol/L) 50% aqueous solution of dihydroxyacetic acid (hydrated glyoxylic acid) and 8.2 parts (0.1 […]

30Jul 2019

Through the static scale inhibition test, we studied the scale inhibition performance of PBTC and HEDP on calcium carbonate scale under low-temperature conditions (2°C-15°C). The results show that the scale inhibition performance of PBTC and HEDP on calcium carbonate scale is good at 2°C-15°C. The initial calcium ion + alkalinity has a great influence on […]

27Jun 2019

The full name of DBNPA is 2-2-dibromo-3-nitriloproion amide. It is a broad-spectrum and efficient industrial fungicide. DBNPA is used to prevent bacteria and algae from growing in papermaking, industrial circulating cooling water, mechanical lubricants, pulp, wood, paint, and plywood. 2-2-Dibromo-3-Nitrilopropionamide (DBNPA) is currently popular at home and abroad. Organic bromine fungicides. Sterilization mechanism of DBNPA […]