Proton Exchange Membrane (PEM) Electrolyser

GF Piping Systems’ polymer piping systems are designed to support the efficient operation of Proton Exchange Membrane (PEM) electrolysers through:

• Chemical Resistance: The polymer pipes are highly resistant to the corrosive effects of the acidic or basic environments in which PEM electrolysers operate.
• Purity Maintenance: They prevent contamination of the ultra-pure water used in PEM electrolysers, ensuring consistent performance and protecting the integrity of the electrolyser.
• Flexibility and Durability: Polymer pipes, such as those made from polypropylene (PP) or Polyvinylidenfluorid (PVDF), are lightweight, flexible, and durable, facilitating easier installation and long-term reliability in handling the high-purity water and gases involved in the electrolysis process.
• Reduced Contamination Risk: Their smooth internal surfaces help minimize the risk of particulate or chemical contamination that could affect the performance of the PEM electrolyser.

By providing reliable, corrosion-resistant, and chemically compatible piping solutions, GF Piping Systems’ polymer pipes enhance the efficiency and longevity of PEM electrolysers.

The Proton Exchange Membrane (PEM) electrolyzer constitutes an advanced apparatus designed for the generation of hydrogen through the process of water electrolysis. In this method, water (H2O) undergoes separation into hydrogen (H2) and oxygen (O2) with the application of electricity. The distinctive feature of the PEM electrolyzer lies in its use of a solid polymer electrolyte, or the Proton Exchange Membrane, facilitating the conduction of protons (positively charged hydrogen ions) from the anode to the cathode while impeding electron flow. This process generates pure hydrogen gas at the cathode and oxygen gas at the anode.

It is particularly well-suited for applications necessitating the production of pure hydrogen, particularly in the realm of fuel cells for energy storage, transportation, and industrial utilization.

The performance and longevity of Proton Exchange Membrane (PEM) electrolysers hinge on the quality of the water used that is fed in. Elevated levels of Total Organic Carbon (TOC*) can compromise the catalysts and membrane, potentially reducing the operational lifespan and thus rise cost of hydrogen.

It is essential to prioritize the use of top-quality materials such as PP-H and implement advanced purification methods to minimize the risk of impurities. Elevated TOC* levels in the water supply may result in the generation of undesirable by-products during the electrolysis process. These by-products can contribute to material degradation and a reduction in operational efficiency. 1

Therefore, it is vital to select materials with resistance to chemical degradation and leaching to safeguard the integrity of the electrolyzer system.

1. Hans Becker et al. (Review Article) Sustainable Energy Fuels, 2023, 7, 1565-1603. DOI: 10.1039/D2SE01517J, Impact of impurities on water electrolysis: a review - Sustainable Energy & Fuels (RSC Publishing) DOI:10.1039/D2SE01517J

*Definition of TOC: Total Organic Carbon (TOC) measures the amount of organic carbon present in water, representing the total concentration of organic molecules that can potentially contaminate the system. It is a critical parameter in assessing the purity of water, especially in applications such as PEM electrolysis, where impurities can significantly impact the efficiency and longevity of the system.

Water purification can be a significant cost factor in producing green hydrogen. For example, deionised water purification can comprise up to 22% of the total balance of plant (BoP) cost of a 1 MW PEM WE system. This cost remains relatively stable regardless of system size or production rate, making it key in scaling hydrogen production. Water purity is essential for electrolysers, as impurities degrade the membrane and catalyst in PEM electrolysers, reducing efficiency and increasing costs, ultimately shortening the stack's lifespan. 1

OEM manufacturers face challenges such as ensuring consistent water purity, managing the cost of water purification systems, and mitigating the impact of impurities on the electrolyser’s performance and lifespan. These challenges require robust water purification technologies and materials that can maintain high purity levels.

Polymers such as Polypropylene Homopolymer (PP-H) and Polyvinylidene Fluoride (PVDF) are used for the ultrapure water because they are highly resistant to corrosion. They do not leach impurities into the water, ensuring the purity of the water remains high. Additionally, they are durable and can withstand the harsh conditions within the electrolyser system.

1. Hans Becker et al. (Review Article) Sustainable Energy Fuels, 2023, 7, 1565-1603. DOI: 10.1039/D2SE01517J, Impact of impurities on water electrolysis: a review - Sustainable Energy & Fuels (RSC Publishing) DOI:10.1039/D2SE01517J
(free access)