Thermo Scientific Prima BT and Prima PRO Process Mass Spectrometers Improving production of green hydrogen with fast, precise gas analysis MS

Importance of the topic

Green hydrogen produced by water electrolysis powered with renewable electricity is a central route toward deep decarbonization across heavy industry, power-to-x and transport. Reliable, high‑speed, and multi‑stream gas analysis is essential for R&D, scale‑up and continuous production because it enables control of product purity, detection of membrane crossover or degradation, dryer performance monitoring, and safe operation when handling hydrogen/oxygen mixtures. Magnetic sector mass spectrometry (MS) with fast multistream sampling can meet these analytical needs across laboratory, pilot and industrial installations.

Objectives and overview of the application note

This application note presents the capabilities and benefits of Thermo Scientific Prima BT (bench) and Prima PRO (process) magnetic sector process mass spectrometers for green hydrogen applications. Key aims are to demonstrate fast, precise analysis of H2, O2 and H2O in various electrolyzer streams, to outline the analytical requirements when scaling electrolyzer systems, and to compare magnetic sector MS with alternative technologies (quadrupole MS and discrete gas analyzers). Practical examples from laboratory and megawatt‑scale electrolyzers illustrate performance and insights enabled by these instruments.

Methodology and analytical requirements

• Analytical targets: rapid, simultaneous quantification of hydrogen, oxygen and water vapor with wide dynamic range (100 % to low ppm) to support purity assessment, troubleshooting and process control.
• Electrolyzer types addressed: alkaline electrolyte membrane (AEM), polymer electrolyte membrane (PEM) and solid oxide electrolysis cells (SOEC), each with characteristic operating temperatures and sampling needs.
• Scaling and multistream monitoring: modular stack architecture requires many measurement points; analytical systems need to provide matched performance from lab to process to avoid correlation errors when transferring methods between instruments.
• Safety and sample handling: when sampling alternating pure hydrogen and pure oxygen streams, inert purge/ dilution and pump purging are required to avoid forming hazardous mixtures and to suppress cross-talk in multistream samplers.

Used instrumentation

• Thermo Scientific Prima BT: benchtop magnetic sector MS for laboratory and R&D scale. Typical configuration supports ~15 sample ports and multiple calibration ports.
• Thermo Scientific Prima PRO and Prima PRO Ex: process magnetic sector MS for industrial deployment with multi‑stream capability (up to 64 streams), hazardous‑area installations (ATEX Zone 1, Class 1 Div 2 options) and industrial networking.
• RMS (Rapid Multistream Sampler): selector device allowing user‑configurable sampling from 1 of 32 or 1 of 64 streams, heated option to 120 °C, optical position encoding, low dead volume design and digital flow logging for each stream.
• GasWorks software: supports unlimited components per stream, unlimited user‑defined calculations (Derived Values), method libraries and plant control system protocols for integration.
• Instrument technology: magnetic sector analyzer with Faraday detection and flat‑top mass peaks, offering high resolution and stability compared to quadrupole MS.

Main results and discussion

• Speed and dynamic range: Prima instruments deliver ~5 s analysis time and can measure components from 100 % down to low ppm in a single measurement, enabling real‑time resolution of changing gas composition during electrolysis experiments.
• Multistream performance: RMS selector settling times are application dependent; example cycle timings indicate ~55 s settling and ~2 min total cycle to measure two streams. The RMS design minimizes dead volume, reduces cross‑talk and includes purging options to safely dilute flammable mixtures.
• Precision and detection limits: Typical Prima PRO performance examples show detection limits and standard deviations at levels appropriate for purity monitoring (e.g., hydrogen detection limits on the order of 0.01–0.05 %mol depending on stream composition; water and oxygen detection at ppm to sub‑percent levels). Prima BT specifications demonstrate similarly low detection limits (CO2 detection down to ~0.001 %mol in example ranges) and high repeatability suited for lab use.
• Insights from case studies: In an R&D mixed H2/O2 stream (≈70:30), MS data helped operators identify over‑filled liquid oxygen in a separator. In a megawatt oxygen stream, water vapor analysis correlated with dew point meter readings and informed dryer regeneration requirements. These examples show the value of direct, multicomponent, high‑speed MS data in process optimization and safety.
• Magnetic sector advantages: Compared with quadrupole MS, magnetic sector instruments provide superior mass stability, precision (reported at least an order of magnitude better than discrete analyzers), and hydrogen resolution because of the flat‑topped peak shape and curved ion flight path that suppresses zero‑blast artifacts common at low masses on quadrupoles.

Benefits and practical applications

• Single‑instrument, multistream monitoring reduces capital and maintenance cost vs multiple discrete gas analyzers while delivering complete gas composition for each sampled stream.
• Fast responses enable real‑time process control, dryer performance monitoring, detection of membrane crossover or degradation and safer operations when handling H2/O2 streams.
• Scalable analytical performance supports method transfer from laboratory R&D (Prima BT) to pilot/industrial process control (Prima PRO) with consistent analytical results.
• Industry use cases include green ammonia production (using green H2 instead of steam methane reforming), iron and steel decarbonization via DRI/EAF processes powered by hydrogen, and general power‑to‑X operations that require precise gas composition control.

Future trends and potential applications

• Integration of high‑precision multistream MS into distributed electrolyzer farms for comprehensive stack health monitoring and predictive maintenance using derived metrics and digital twins.
• Expanded use of magnetic sector MS data to support advanced control strategies (model predictive control) that optimize energy efficiency and minimize parasitic losses in electrolyzer systems.
• Increased on‑line monitoring for hydrogen quality assurance in refueling stations, grid injection, and long‑term storage pathways, supporting regulatory compliance and certification frameworks for hydrogen carriers.
• Potential coupling with isotope or trace impurity analysis to monitor catalyst poisoning, membrane degradation products and long‑term component life‑cycle diagnostics.

Conclusion

Magnetic sector mass spectrometry (Thermo Scientific Prima BT and Prima PRO) provides rapid, precise, and scalable multistream gas analysis meeting the stringent analytical requirements of green hydrogen production. Its combination of wide dynamic range, low detection limits, multistream sampling capability and industrial readiness supports R&D, pilot and full‑scale electrolyzer deployments. The technology enables actionable process insights — from purity specification to dryer optimization and membrane monitoring — and is well positioned to support an expanding green hydrogen economy across heavy industry and power‑to‑X applications.

References

• European Commission. Energy. (reference to European Commission Energy page cited in source document).
• International Energy Agency. Iron and Steel Technology Roadmap. October 2020.
• U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy. Hydrogen Shot. 7 June 2021.