What is deoxygenating and sterilizing corrosion inhibitor?

      Deoxygenating and sterilizing corrosion inhibitor is a multifunctional water treatment agent that integrates deoxygenation, sterilization, and corrosion inhibition functions. It is widely used in the field of industrial water treatment, especially in boiler water treatment, circulating cooling water systems, and other scenarios. The following will introduce it from several aspects, including its definition, principle of action, composition of components, and application scenarios.

1. Definition and Function Overview

      Deoxygenating and sterilizing corrosion inhibitors are composite agents developed to address issues such as dissolved oxygen, microbial growth, and corrosion of metal equipment in water systems. It achieves the functions of removing dissolved oxygen in water, killing or inhibiting microbial growth, and slowing down metal corrosion rate through multiple mechanisms of action, thereby ensuring the safe and stable operation of water systems, extending equipment service life, and reducing maintenance costs.

2. Working principle

      （1） Deoxygenation effect

      Deoxygenation is one of the important functions of this medication. Dissolved oxygen in water is one of the main factors causing corrosion of metal equipment. It reacts with metals to oxidize, accelerating the corrosion process of metals. The deoxygenation components in deoxygenating and sterilizing corrosion inhibitors, such as ascorbic acid and its sodium salt, can react chemically with dissolved oxygen in water, reducing oxygen and effectively inhibiting the occurrence of oxygen corrosion. For example, isoascorbic acid can reduce dissolved oxygen to water and oxidize itself to dehydroascorbic acid. The reaction equation is: C6 H8O6+O2 → C6 H6 O6+H2O2

      The reaction between ascorbic acid and oxygen is more complex in reality. Through this reaction, dissolved oxygen in water is continuously consumed to maintain its concentration at a lower level.

      （2） Sterilization effect

      Various microorganisms, such as bacteria, fungi, and algae, are prone to breed in water systems. These microorganisms can form biofilms on metal surfaces, which not only hinder heat exchange and reduce equipment efficiency, but also accelerate metal corrosion. The bactericidal components in deoxygenating and sterilizing corrosion inhibitors, such as quaternary ammonium compounds, can damage the cell membrane structure of microorganisms, change the permeability of the cell membrane, and cause substances inside the cells to leak out, leading to microbial death. Quaternary ammonium salts carry a positive charge, while microbial cells carry a negative charge. Electrostatic adsorption occurs between them. After entering the cell, quaternary ammonium salts react with proteins or lipids inside the cell, interfering with the normal metabolic process of microorganisms and achieving the purpose of sterilization.

      （3） Corrosion inhibition effect

      The corrosion inhibitor component in this agent can form a protective film on the metal surface, preventing corrosive media in water (such as water, oxygen, acid, salt, etc.) from directly contacting the metal, thereby slowing down the corrosion rate of the metal. The protective film can be a physical adsorption film, a chemical precipitation film, or an oxide film, etc. For example, some organic amine and organic acid corrosion inhibitors can adsorb onto metal surfaces, changing the charge state and reactivity of the metal surface, making it less prone to react with corrosive media; Phosphate corrosion inhibitors can form insoluble precipitates with calcium, magnesium ions, and other substances in water, depositing a protective film on the metal surface.

3. Composition of ingredients

      Deoxygenating and sterilizing corrosion inhibitors are usually composed of multiple components that work together to exert a comprehensive effect. The common ingredients and their functions are shown in the table below:

      

Component type	Specific components	Effect
Oxygen scavengers	Isoascorbic acid, sodium isoascorbate	Reacts with dissolved oxygen to reduce oxygen content in water
Fungicide	Quaternary ammonium salt compounds (such as alkyl trimethylammonium chloride, dimethyl benzyl alkyl ammonium chloride, etc.)	Destroy microbial cell membranes and kill microorganisms
Corrosion inhibitor	Organic amines (such as dimethylamine), organic acids (such as oxalic acid, citric acid), phosphates (such as sodium dihydrogen phosphate), sodium epoxysuccinate, sodium hexametaphosphate, polyaspartic acid, etc	Form a protective film on the metal surface to slow down metal corrosion
Other auxiliary components	PH regulators, dispersants, etc	Adjust the pH value of water to enable the medication to function in a suitable acidic and alkaline environment; Disperse suspended solids in water to prevent sedimentation and blockage of pipelines

4. Application scenarios

      （1） Boiler water treatment

      During the operation of the boiler, dissolved oxygen in the water can cause oxygen corrosion of the metal heating surface of the boiler, producing corrosion products that affect the thermal efficiency and service life of the boiler. At the same time, the growth of microorganisms in the boiler can form biofouling, block pipelines, and reduce heat transfer efficiency. Deoxygenating and sterilizing corrosion inhibitors can effectively remove dissolved oxygen from water, kill microorganisms, and form a protective film on the metal surface of boilers to prevent corrosion and scaling, ensuring the safe and economical operation of boilers.

      （2） Circulating cooling water system

      Circulating cooling water systems are widely used in industrial production, but are susceptible to the effects of dissolved oxygen, microorganisms, and corrosion. The use of deoxygenating and sterilizing corrosion inhibitors can control the oxygen content in water, inhibit the growth and reproduction of microorganisms, slow down the corrosion rate of metal pipelines and equipment, extend the service life of the system, reduce maintenance and replacement costs, and improve production efficiency.
      With the rapid development of industry, the demand for water treatment agents is increasing day by day. Deoxygenating and sterilizing corrosion inhibitors, as one of the important water treatment agents, have broad development prospects. In the future, it is expected to further improve its performance, such as developing more efficient and environmentally friendly deoxygenating and sterilizing corrosion inhibitors, and enhancing the overall performance of the drug; Continuously expanding in application fields to adapt to more complex water quality and equipment conditions. Meanwhile, with the development of intelligent technology, the addition and monitoring system of deoxygenating and sterilizing corrosion inhibitors will become more intelligent and automated, bringing more convenience and efficiency to industrial water treatment. I believe that in the near future, deoxygenating and sterilizing corrosion inhibitors will play a more important role in the industrial field.