Sodium Borohydride for Hydrogen Mobility & Compression

Background

Sodium borohydride (NaBH₄) releases hydrogen on contact with water, and that hydrolysis reaction can be driven and controlled with an acid catalyst rather than a separate fixed catalyst bed. In collaboration with Hyundai Motor Company, I’ve spent roughly 2023 through 2026 working on a series of studies that use this one reaction — acid-mediated NaBH₄ hydrolysis — as the chemical backbone for producing hydrogen at the pressures real-world refueling needs, without depending on grid power or a mechanical compressor.

That work builds on the group’s earlier research on an onboard hydrogen generator of roughly 20 kWe, published in Chemical Engineering Journal in 2023 — a project I wasn’t part of, but one that established acid-mediated NaBH₄ hydrolysis as a compact, on-demand hydrogen source before I joined the effort.

From there, the arc I contributed to runs along two threads. The first pushes the same chemistry to increasingly higher pressure, replacing mechanical compression outright: sequential sodium-borohydride-and-formic-acid reactions to 650 bar, then a closer look at the catalyst mechanisms behind clean, high-purity output at 950 bar, culminating in a grid-independent mobile refueling system running at 500 bar. The second thread closes a loop the first one opens — the same reaction that produces hydrogen also produces a carbon monoxide byproduct that has to be scrubbed to meet purity specifications, and that purification problem became its own line of catalyst and patent work, using the reactor’s own heat to do it.

What I did

• Contributed conceptualization and techno-economic assessment to the sequential sodium-borohydride-and-formic-acid compression study reaching 650 bar.
• Investigated catalyst mechanisms behind high-purity, high-pressure hydrogen output at 950 bar.
• Led the arc’s peak result as first author: a grid-independent, mobile hydrogen refueling system that generates hydrogen at 500 bar without a mechanical compressor.
• Ran XPS surface analysis and reaction performance evaluation for a low-temperature CO purification catalyst that scrubs the reactor’s own CO byproduct — work that fed into a filed patent application.

Outcomes

The arc’s peak is a working system, not just a lab result: a grid-independent hydrogen generator that reaches 500 bar directly from sodium borohydride hydrolysis, replacing a mechanical compressor stage entirely. That distinction matters for mobile and remote refueling scenarios where a conventional compressor stage — with its power draw, footprint, and maintenance burden — isn’t practical. It’s described in a first-author paper in Chemical Engineering Journal: from lab bench to a working high-pressure, grid-independent hydrogen generator.

Publicly demonstrated at ADEX 2025.

The CO purification thread closes the loop on the platform’s own byproduct chemistry — the same reaction that produces hydrogen also produces CO that has to be scrubbed to meet purity specs, and that purification step runs on the reactor’s own heat. It spans a filed patent application, a co-authored paper on the catalyst behind it, and a manuscript currently under review at the International Journal of Hydrogen Energy.

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