Decarbonising global fleets of commercial and off-road vehicles, and reducing CO₂ emissions must be a priority for the industry. At Dinex we see the necessity of a multi-technology approach, where the most suitable technology is selected for different applications with different requirements.

We strongly believe that the Internal Combustion Engine (ICE) will play a significant role in this transition and

decarbonisation journey, alongside electrification and Fuel Cells. Since the problem is not the engine but what it burns, using H₂ as a fuel in the ICE has a very strong potential for a lifecycle CO₂ reduction. This is because H₂ contains no carbon and hence emits no CO₂ when it burns in the ICE. In addition, the H₂ ICE keeps all advantages of the ICE, such as range, payload, fast refilling, availability and robustness, while allowing OEMs and fleet operators to utilise their existing dealer network for maintenance and repairs at reduced costs and well-known serviceability.

Exhaust Aftertreatment for H₂ Engines

H₂ engines generate lower amounts of raw emissions compared to diesel engines. Nevertheless, data and testing show that an ATS is still required to eliminate any unburned H₂ from the combustion process, NOX generated from the combustion of H₂ with air and particles generated from the lubricant, especially when the target is reaching near-zero tailpipe emissions. In addition, there is a strong requirement on the ATS not to generate any unwanted emissions, such as N₂O, which is a powerful greenhouse gas.

Moreover, the exhaust gas of a H₂ engine has different properties compared to a diesel engine, the main characteristic being the very high water content. This means that the ATS needs to be tailored to those unique needs.

Dinex in full progress for H₂ engines

At Dinex we saw the potential of this technology quite early and established early partnerships to understand the specific characteristics of the H₂ engine, in order to develop a tailored ATS solution. Thanks to our dual coating and  canning competence, we have designed catalytic coatings and a complete ATS that fit the exact requirements of a H₂ engine:

• A cost-optimised catalyst to eliminate any unburned H₂ emissions.

• A catalyst to store NO_X emissions at cold start and passively release them when the main SCR is ready to remove them.

• An ammonia-SCR system with a special SCR washcoat to support near-zero tailpipe NO_X and avoid any N₂O emissions.

• A muffler with the right material selection to resist the very high H₂O content in the exhaust gas.

• Optional, a passive particulate filter for any particles escaping from the engine lubricant oil.

Dinex is already engaged in the development of application specific H2-ICE solutions for both on- and off-road customers, and has published several papers on the topic:

T. Wolff et al. (2022), Eine Lösung auf dem Weg zu ultra-low NO_X Emissionen von Wasserstoff-Verbrennungsmotoren, FAD Konferenz

M. Geist et al. (2022), Comparison and Evaluation of SCR catalysts for hydrogen internal combustion engines, 8^th International MinNO_X Conference for Sustainable Mobility

V. Huth et al. (2021), The Hydrogen Combustion Engine as Zero Impact Emission Powertrain Concept, 30^th Aachen Colloquium Sustainable Mobility

Moreover, Dinex was the only ATS supplier to present a dedicated ATS for the H₂ engine at the recent IAA 2022 and BAUMA 2022 exhibitions in Hannover and Munich respectively.

Want to learn more about Dinex’ solutions for Hydrogen Combustion Enegines? Check out these test-results HERE.