Petronor looks to new membrane tech to boost existing grey hydrogen output

Repsol’s Petronor subsidiary is looking to boost grey hydrogen production output by integrating membrane technology into a new “first-of-a-kind’ system” at its refinery operations.

Under a new agreement with membrane firm H2Site, Petronor could use H2Site’s technology in on-site steam methane reforming (SMR) equipment – enabling greater hydrogen yield and enhancing carbon capture and storage opportunities.

The Bilbao-based firm has been developing membrane reactor technology since 2021, which enables hydrogen separation from gas streams and green molecules such as ammonia or methanol.

It improves SMR by pulling hydrogen out of the reaction as it forms using a selective palladium membrane. This simultaneously increases hydrogen production and removes the need for a separate purification system.

Andrés Galnares, CEO of H2Site, said the agreement will allow the firm to demonstrate its membrane reactor at refinery scale, improving hydrogen recovery, lowering net energy demand, and de-risking the technology’s commercial rollout.

Petronor, which is owned by Repsol and Kutxabank, operates one of Spain’s largest oil refineries with capacity of 220,000 barrels of crude oil per day.

A timeline for the rollout has not been revealed.

Hydrogen plays a crucial role across refining, maximising yields, processing lower-quality crude, and enabling compliance with fuel specifications.

It is primarily used in hydrotreating for removing sulphur impurities from fuels, and in hydrocracking to convert heavy crude into lighter, higher-value products like diesel and jet fuel.

With existing hydrogen production accounting for approximately 2.5% of global carbon dioxide emissions, optimising existing grey hydrogen assets is seen as key to cleaning up the molecule and reducing costs.

A September 2025 whitepaper by Technip Energies said that process intensification could future-proof grey hydrogen assets. This focuses on squeezing more hydrogen from the same feedstock while cutting CO2 intensity.