12 May Blog | Catalytic Innovation in Action: Advancing Air Quality Monitoring with the MI-TRAP Project
by Hans Joachim Schulz | Catalytic Instruments GmbH & Co. KG
Transport-related air pollution is one of the leading causes of poor urban air quality and associated health risks across Europe. Despite progress in emissions legislation, real-world data often reveal that pollutants from vehicles, aircraft, and trains continue to challenge existing monitoring methods. The Horizon Europe-funded MI-TRAP project (Mitigating Transport-Related Air Pollution) seeks to bridge this gap by developing advanced technologies for precise, real-time monitoring of air pollutants.
As a central technology partner in MI-TRAP, Catalytic Instruments GmbH & Co. KG contributes one of the project’s key innovations: the °Catalytic Stripper, a device that enables artifact-free detection of solid particles. This blog post explores our role in the project, the science behind our solution, and the real-world impact it enables.
The °Catalytic Stripper – Cutting-Edge Technology for Cleaner Air
At the heart of our contribution is the °Catalytic Stripper (CS), an advanced aerosol treatment device that removes volatile and semi-volatile organic compounds (VOCs/SVOCs) from exhaust and ambient aerosols. These substances, if not removed, can re-condense downstream and create false measurement artifacts. The CS ensures that only the solid particle fraction – the most health-relevant – is measured.
Highlights of the Technology:
- High oxidation efficiency at temperatures up to 400°C.
- Minimal particle losses due to optimized design.
- Versatile flow rates: from 0.1 L/min to over 3.0 L/min.
- Compact models for mobile monitoring (e.g., CCS004), and high-throughput models for stationary systems (e.g., CS015).
- Extensively tested in both laboratory and real-world scenarios.
Internal structure of the CS015, showcasing the oxidation chamber, heat exchanger, and digital temperature interface.
Why °Catalytic Strippers Outperform Thermal Denuders
A direct comparison with thermal denuders shows the superiority of catalytic technology:
- No re-nucleation artifacts (a common problem with TDs).
- Stable operation under complex aerosol conditions.
- Higher particle removal efficiency (up to 99.99% for tetracontane aerosols).
- No risk of false particles emission flows the CS versus the TD, that shows significant artefacts bellow 10 nm.
Independent experiments1 (Swanson & Kittelson, 2010) and internal tests confirmed that thermal denuders fail under complex organic/sulfuric aerosols, generating false particles downstream. In contrast, °Catalytic Strippers maintain measurement integrity, even under stress. These aerosols were introduced into three different setups: a TD alone, a Catalytic Stripper (CS) alone, and a combination of TD followed by CS.
MI-TRAP Applications – Real-World Impact across Europe.
To achieve the MI-TRAP goals, Catalytic Instruments developed 12 tailor-made °Catalytic Stripper units:
- 6 Compact Strippers (CCS004, 0.4 L/min)
- 6 High-Flow Strippers (CS015/CS03, 1.5–3.0 L/min)
These devices were installed in urban monitoring stations across Athens, Copenhagen, and Zurich, as well as in high-emission environments like airports, ports, and railway hubs. Each location was chosen to assess specific emission sources under real-world conditions.
Scientific Validation – Testing, Calibration, and Standardization
Catalytic Instruments conducted comprehensive validation of its devices using silver particles, tetracontane, and interlaboratory comparison campaigns. Key results:
- Tetracontane removal efficiency: 99.9999% (CS015)
- Particle penetration efficiency: 75% for 100 nm, 50% for 15 nm, verified at PTB and METAS.
- Power consumption: ultra-low (7W after warm-up for CCS004).
Broader Use Cases – Beyond MI-TRAP
The °Catalytic Stripper is not only valuable in air quality monitoring but is a crucial tool in a range of domains:
- Automotive emissions (Euro 6/7, PMP-compliant).
- Aviation and marine emissions.
- Environmental health and toxicology.
- Industrial and laboratory calibration studies.
- Medical research involving ultrafine particle exposure.
Its CE certification, modular design, and energy efficiency make it adaptable for global deployment – from portable units in cities to high-end setups in national labs.
The MI-TRAP project showcases what’s possible when science and engineering unite for environmental progress. At the core of this initiative is the °Catalytic Stripper (CS), a compact and high-efficiency device that selectively removes volatile and semi-volatile organic compounds (VOCs/SVOCs) from exhaust and ambient aerosols. By preventing re-condensation and eliminating measurement artifacts, it ensures accurate quantification of the solid particle fraction—crucial for health and regulatory assessments. With oxidation temperatures up to 400°C, minimal particle loss, and proven performance across diverse field conditions, the °CS has redefined reliability in aerosol measurement.
What’s next?
Building on this foundation, our technology is now being integrated into major European atmospheric monitoring frameworks, delivering real-time, high-integrity data to inform environmental policy and air quality standards. This expanded role supports better emission modeling, exposure assessment, and source tracking. Future developments are focused on enhancing performance at low particle concentrations and extending applications into emerging fields—such as climate-sensitive studies involving black carbon and secondary organics, as well as medical diagnostics and indoor air quality monitoring, where precise particle characterization is essential.
About
Hans-Joachim Schulz: Managing Director, Catalytic Instruments, Physicist & Project lead
- SWANSON, J.; KITTELSON, D. Journal of Aerosol Science, v. 41, p. 1113–1122, 2010. ↩︎