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1. Introduction
As a critical piece of equipment in the chemical industry, electrolyzers are prone to corrosion due to long-term exposure to chemical media, adversely affecting their performance, service life, and particularly threatening production safety. Therefore, implementing effective anti-corrosion measures is essential. Currently, some enterprises use materials like rubber-plastic composites or vulcanized butyl rubber for protection, but the results are often unsatisfactory. While effective initially, the anti-corrosion performance significantly degrades after 1-2 years, leading to severe damage. Considering both technical and economic factors, Glass Fiber Reinforced Polymer (GFRP) rebar is an ideal choice for corrosion-resistant materials in electrolyzers. Besides possessing excellent mechanical properties, GFRP rebar also demonstrates outstanding chemical corrosion resistance, garnering widespread attention from chlor-alkali industry enterprises. As one of the most widely used corrosion-resistant materials, it is particularly suitable for equipment exposed to media such as chlorine, alkalis, hydrochloric acid, brine, and water. This article primarily introduces the application of GFRP rebar, using glass fiber as the reinforcement and epoxy resin as the matrix, in electrolyzers.

2. Analysis of Corrosion Damage Factors in Electrolyzers
Apart from being influenced by the electrolyzer’s own material, structure, and construction techniques, corrosion primarily stems from external corrosive media. These include high-temperature wet chlorine gas, high-temperature sodium chloride solution, chlorine-containing alkali liquor, and high-temperature saturated chlorine water vapor. Furthermore, stray currents generated during the electrolysis process can accelerate corrosion. The high-temperature wet chlorine gas produced in the anode chamber carries a significant amount of water vapor. Hydrolysis of chlorine gas produces highly corrosive hydrochloric acid and strongly oxidizing hypochlorous acid. The decomposition of hypochlorous acid releases nascent oxygen. These media are chemically highly active, and except for titanium, most metallic and non-metallic materials suffer severe corrosion in this environment. Our plant originally used steel shells lined with natural hard rubber for corrosion protection. Its temperature resistance range was only 0–80°C, which is lower than the ambient temperature of the corrosive environment. Moreover, natural hard rubber is not resistant to hypochlorous acid corrosion. The lining was susceptible to damage in vapor-liquid environments, leading to corrosive perforation of the metal shell.

3. Application of GFRP Rebar in Electrolyzers
3.1 Characteristics of GFRP Rebar
GFRP rebar is a new composite material manufactured by pultrusion, using glass fiber as the reinforcement and epoxy resin as the matrix, followed by high-temperature curing and special surface treatment. This material offers excellent mechanical properties and outstanding chemical corrosion resistance, particularly outperforming most fiber products in resistance to acid and alkali solutions. Additionally, it is non-conductive, non-thermally conductive, has a low coefficient of thermal expansion, and possesses good elasticity and toughness. The combination of glass fiber and resin further enhances its corrosion resistance. It is precisely these prominent chemical properties that make it the preferred material for corrosion protection in electrolyzers.

Within the electrolyzer, GFRP rebars are arranged parallel within the tank walls, and vinyl ester resin concrete is poured between them. After solidification, this forms an integral structure. This design significantly enhances the tank body’s robustness, resistance to acid and alkali corrosion, and insulation properties. It also increases the internal space of the tank, reduces maintenance frequency, and extends service life. It is particularly suitable for electrolysis processes requiring high strength and tensile performance.

3.3 Advantages of Using GFRP Rebar in Electrolyzers
Traditional electrolyzer corrosion protection often employs resin-cast concrete methods. However, concrete tanks are heavy, have long curing periods, result in low on-site construction efficiency, and are prone to bubbles and uneven surfaces. This can lead to electrolyte leakage, corroding the tank body, disrupting production, polluting the environment, and incurring high maintenance costs. Using GFRP rebar as an anti-corrosion material effectively overcomes these drawbacks: the tank body is lightweight, has high load-bearing capacity, excellent corrosion resistance, and superior bending and tensile properties. Simultaneously, it offers advantages such as large capacity, long service life, minimal maintenance, and ease of hoisting and transportation.

4. Summary
Epoxy-based GFRP rebar combines the excellent mechanical, physical, and chemical properties of both components. It has been widely applied to solve corrosion problems in the chlor-alkali industry and in concrete structures like tunnels, pavements, and bridge decks. Practice has shown that applying this material can significantly enhance the corrosion resistance and service life of electrolyzers, thereby improving production safety. Provided the structural design is reasonable, the material selection and proportions are appropriate, and the construction process is standardized, GFRP rebar can greatly enhance the anti-corrosion performance of electrolyzers. Consequently, this technology holds broad application prospects and is worthy of widespread promotion.