Ball Valves for Hydrogen Production – Potassium Hydroxide (KOH)

The increasing demand for safe, efficient, and reliable handling of chemical process fluids makes Potassium Hydroxide (KOH), commonly known as caustic potash, a critical focus area in industries such as fertilizers, biodiesel, chemical synthesis, batteries, food sector, and more recently, the production of Hydrogen gas (H₂). Particularly in hydrogen production by electrolysis of water, with pressures up to around 40 bar, KOH is widely used as a reliable electrolyte. It increases the electrical conductivity of water, lowers the energy consumption and the internal resistance, facilitating the breakdown into hydrogen (H₂) and oxygen (O₂). This application has gained more importance with the rising demand for cleaner energy sources, as hydrogen has re-emerged as a potential key player in the energy transition.

Although hydrogen has been used in industry for many years, its primary source – around 95% of global production – remains fossil-fuel based, mainly through Steam Methane Reforming (SMR), Partial Oxidation (POX), or Autothermal Reforming (ATR), producing Syngas (a mixture of H₂ and CO). Today, the largest hydrogen consumers are petroleum refining, ammonia and methanol production, representing about 90% of the global demand. However, hydrogen applications in energy systems (blending with natural gas), power storage, and mobility (pressurized hydrogen up to ~500 bar for trucks and ~700 bar for cars) are becoming increasingly relevant in the context of decarbonization and climate goals.

Despite its advantages, KOH presents challenges due to its strong alkaline nature. It is highly corrosive in both liquid and concentrated solution form, requiring equipment specifically designed to withstand chemical attack, prevent leakage, and ensure process safety. Standard industrial valves not designed for corrosive service can suffer rapid degradation, seal failure, or premature leakage, leading to significant safety and operational risks.

Design Considerations

Hydrogen ball valves must comply with essential safety and performance requirements, particularly:

• Chemical compatibility – materials as carbon steel, bronze, PTFE filled with carbon or FKM elastomers are examples of materials that will degrade in contact with KOH. The common and suitable metallic materials applied for this application are stainless steel 316/L or CF8M. In some cases, where more longevity is required, materials such as stainless steel 904L, alloy 20 or CN7M are specifically available to enhance the durability of the process in good conditions. All these materials are suitable and prevent hydrogen embrittlement due to its low yield strength, conferring higher elongation, reducing the hydrogen embrittlement potential. Regarding the polymeric materials, pure PTFE and TFM are applied for the seals, seats, and packing of the valve. For cases where the application of an O’ring is required, it is possible to introduce FFKM elastomer keeping the chemical compatibility and pressure containing capability of the valve.
• Fire-safe performance validated by ISO 10497 and API 607 testing, ensuring fire safe proven design.
• Low emissions packing validated by ISO 15848-1 testing, ensuring high levels of tightness.
• Antistatic design, as required by 2014/34/EU directive, ISO 80079-36/37 and ASME B16.34, API 6D, or ISO 17292, to mitigate risks of ignition in case of abnormal operation.
• SIL-compliant design (SIL 3), in accordance with IEC 61508 and IEC 61511 standards, to ensure functional safety and mitigate risks in safety-instrumented systems during abnormal operation.

Available certification (standards and references)

• PED 2014/68/EU – Pressure equipment directive.
• ATEX 2014/34/EU and ISO 80079-36/37 – Explosive atmospheres / classified zones 1, 2, 21, 22 (IIC).
• ISO 15848-1 – Low emission type test.

Hydrogen products for KOH

CFH / XFH / QFH / VTH / CTH

Conclusion

Hydrogen ball valves are critical components in hydrogen infrastructure. Their design must guarantee safe and reliable tightness performance with the thinner fluid known, fulfilling international standards and directives. The use of validated hydrogen valves reduces operational risks, ensures regulatory compliance, and provides confidence in long-term system integrity.