Electrolytic Water AEM

Electrolytic water AEM refers to the anion exchange membrane (Anion Exchange Membrane) electrolysis water technology. The following is a detailed introduction to it:

Basic principle

Membrane function and ion transport: The anion exchange membrane is the core component of this technology. It has the function of selectively permeating anions. In the electrolytic water system, when direct current is passed, the anion exchange membrane allows hydroxide ions (OH⁻) to pass through, while it has a blocking effect on other ions. Under the action of the electric field, the hydroxide ions (OH⁻) in the electrolyte can pass through the anion exchange membrane and move from the cathode side to the anode side, thereby participating in the electrode reaction and maintaining the entire electrolysis process.
Cathode reaction (reduction reaction): At the cathode, water obtains electrons to undergo a reduction reaction to generate hydrogen and hydroxide ions. The reaction formula is: 2H₂O + 2e⁻ → H₂↑ + 2OH⁻. In addition to partially adding the newly generated hydroxide ions to the electrolyte to maintain the ion concentration balance, some of them will migrate to the anode through the anion exchange membrane under the action of the electric field.
Anode reaction (oxidation reaction): At the anode, the hydroxide ions (OH⁻) that migrated from the cathode side through the anion exchange membrane lose electrons and undergo oxidation reaction to generate oxygen and water. The reaction formula is: 4OH⁻ – 4e⁻ → O₂↑ + 2H₂O. Oxygen escapes from the anode in the form of gas, and the generated water is added to the electrolyte on the anode side to participate in subsequent ion conduction and other processes.
Overall water electrolysis reaction: Combining the reactions of the cathode and anode, the overall chemical reaction equation also follows 2H₂O = power on = 2H₂↑ + O₂↑, that is, the process of decomposing water into hydrogen and oxygen under power on conditions, which is consistent with other water electrolysis technologies in the final material conversion results.

Characteristics of anion exchange membrane (AEM)

Ion selectivity: It has good selective permeability for hydroxide ions (OH⁻), can effectively block cations and other anions, ensure that the electrolysis reaction proceeds according to the established electrode reaction path, and avoids disordered reactions of different ions on the electrode surface, thereby ensuring the efficient generation and separation of hydrogen and oxygen.
Chemical stability: It needs to have a certain chemical stability and can exist stably for a long time in the electrolyte environment (usually containing components such as alkali solution) without chemical changes such as degradation and dissolution, so as to maintain the continuous and stable operation of the water electrolysis process. For example, some high-performance AEM materials can maintain stable performance for months or even years under strong alkaline conditions.
Mechanical properties: It must have sufficient strength and flexibility to adapt to the installation and operation processes in the electrolyzer, and will not be damaged by external forces such as electrolyte flushing and electrode extrusion, affecting the normal operation of water electrolysis.

Comparison with other water electrolysis technologies

Comparison with alkaline water electrolysis technology (AWE):
– Similarities: Both operate in an alkaline electrolyte environment, and the electrode reaction principles are similar, both use the oxidation reaction of hydroxide ions at the anode to achieve water electrolysis.
– Differences: Alkaline water electrolysis technology often uses asbestos as a diaphragm material to separate hydrogen and oxygen, while the anion exchange membrane used in AEM water electrolysis technology is more accurate and efficient in terms of ion selectivity, and AEM water electrolysis technology can theoretically operate at a lower alkali concentration, reducing some potential risks caused by high alkali concentration (such as increased corrosion, etc.), and at the same time has certain advantages in reducing the volume of the electrolyzer and increasing energy density.
Comparison with proton exchange membrane water electrolysis technology (PEMWE):
– Differences: PEMWE relies on the selective permeation of protons (H⁺) through proton exchange membranes to achieve the electrolysis process, while AEM operates through the conduction of hydroxide ions (OH⁻) through anion exchange membranes; PEMWE usually requires the use of precious metal catalysts (such as platinum, iridium, etc.) to reduce the reaction overpotential and improve the reaction efficiency, and the cost is relatively high, while AEM water electrolysis technology can use relatively cheap non-precious metal catalysts because it operates in an alkaline environment, and has certain potential in cost control; in addition, PEMWE has high requirements for water quality, while AEM has relatively less stringent requirements for inlet water quality.

Advantages and application prospects

Advantages:
– Cost advantage: As mentioned above, non-precious metal catalysts and relatively easier to obtain and lower-cost membrane materials can be used, which is expected to reduce the cost of the entire water electrolysis hydrogen production system, making it more economically competitive in large-scale hydrogen production application scenarios.
– Flexibility and compatibility: The requirements for influent water quality and electrolyte concentration are relatively loose, which makes it better adaptable to different raw water sources and deployed in some simpler industrial environments, and can be well coupled with a variety of renewable energy power generation systems (such as solar energy, wind energy, etc.) to achieve green hydrogen production.
Application prospects: In the field of renewable energy hydrogen production, AEM water electrolysis technology can be used as an effective means of hydrogen production. In conjunction with intermittent power sources such as wind power and photovoltaic power, excess electrical energy can be converted into chemical energy (hydrogen) and stored for subsequent energy utilization, such as providing hydrogen fuel for fuel cell vehicles, or as a raw material in chemical production to participate in ammonia synthesis, hydrogenation refining and other processes, to help energy transformation and the sustainable development of the chemical industry.

Challenges

Membrane performance improvement: Although anion exchange membranes have been developed to a certain extent, the ion conductivity of some membrane materials is not high enough, which limits the reaction rate and efficiency of water electrolysis. It is necessary to further develop AEM materials with higher ion conductivity to accelerate the migration speed of hydroxide ions and improve hydrogen production efficiency.
Catalyst durability: Although non-precious metal catalysts can be used, the durability and stability of these catalysts during long-term operation need to be improved. They are prone to problems such as reduced activity and deactivation, which affect the long-term stable operation of the water electrolysis system. In-depth research is needed to improve the structure and composition of the catalyst to enhance its durability.
System integration optimization: To achieve the leap from laboratory to large-scale industrial application of AEM water electrolysis technology, many problems in the entire system integration process need to be solved, such as how to optimize the design of the electrolyzer, how to better connect with the front-end energy supply system and the back-end hydrogen storage and application system, etc., to ensure the efficient and stable operation of the entire hydrogen production industry chain.

Overall, the water electrolysis AEM technology has good development prospects and application potential. With the gradual overcoming of related technical difficulties, it is expected to play an important role in the future green hydrogen production field.

Hydrogen production by electrolysis of water is the most advantageous method for producing hydrogen. Utrasonic coating systems are ideal for spraying carbon-based catalyst inks onto electrolyte membranes used for hydrogen generation. This technology can improve the stability and conversion efficiency of the diaphragm in the electrolytic water hydrogen production device. Cheersonic has extensive expertise coating proton exchange membrane electrolyzers, creating uniform, effective coatings possible for electrolysis applications.

Cheersonic ultrasonic coating systems are used in a number of electrolysis coating applications. The high uniformity of catalyst layers and even dispersion of suspended particles results in very high efficiency electrolyzer coatings, either single or double sided.

About Cheersonic

Cheersonic is the leading developer and manufacturer of ultrasonic coating systems for applying precise, thin film coatings to protect, strengthen or smooth surfaces on parts and components for the microelectronics/electronics, alternative energy, medical and industrial markets, including specialized glass applications in construction and automotive.

Our coating solutions are environmentally-friendly, efficient and highly reliable, and enable dramatic reductions in overspray, savings in raw material, water and energy usage and provide improved process repeatability, transfer efficiency, high uniformity and reduced emissions.

Chinese Website: Cheersonic Provides Professional Coating Solutions