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The utilization of hydrogen and hydrogen-based fuels is a promising option to reduce greenhouse gas emissions of heavy-duty vehicles. Here, the production of sustainable hydrogen plays a key role. Very promising is the production of hydrogen by means of water electrolysis that links fluctuating electricity production from renewable sources with sectors based on chemical energy carriers. Water electrolysis will be one of the key technologies to reduce the energy system transformation costs and to stabilize the electricity grid. Hydrogen can be used directly as a fuel in heavy-duty vehicles or converted with CO2 to fuels like methanol or Fischer-Tropsch products. Methanol can be used both as a fuel and as feedstock for further upgrading to fuels like dimethyl ether (DME), oxymethylene ether (OME), methanol-to-gasoline (MtG) and methanol-to-jet fuel. Recently, also the conversion of hydrogen with nitrogen to ammonia as fuel gains increasing interest in combustion engines. Beyond CO2 reduction exhaust gas emissions have also to be reduced significantly. CatVap® is an innovative fuel processing technology that enables efficient exhaust gas treatment in order to achieve near-zero emission mobility. In addition, hydrogen can be used to operate fuel cell power trains, which is more and more discussed for heay-duty applications. Now it’s the time for a broader market introduction of hydrogen and hydrogen-based fuels in the mobility sector and thus, for cost reduction due the corresponding scale-effects.

Synthetic fuels and fuel blends like OMEs can contribute to tank-to-wheel CO2 emission savings. At the same time, it is known that these fuels have a lower exhaust temperature compared to conventional diesel. This effect has major impact on the exhaust after-treatment system, particularly in cold start conditions. This paper investigates the light-off behavior of exhaust gases containing OMEs by temperature-programmed oxidation experiments using a state-of-the-art oxidation catalyst. The main side product of catalytic oxidation of OMEs between 100 °C and the oxidation temperature T50, which was around 160 °C, was shown to be formaldehyde. While alkane oxidation, in this case heptane, was little influenced by OME oxidation, the oxidation temperature T50 of CO increases by more than 10 °C by OME addition. Nitrogen monoxide impeded the oxidation of OME in a similar way to the other components investigated. Due to the amount of FA produced and its toxicity, it could be concluded that it is necessary to heat up exhaust after-treatment systems of OME diesel engines even faster than conventional diesel exhaust after-treatment systems. The relatively high reactivity of OME on oxidation catalyst can be used by active thermal management approaches.

Today's challenge is to comply 100% with emission limits in Real Drive Emission (RDE) behavior, especially in the cold season, the so-called "cold city rides" that are characterized by the fact that during stop and go rides in the city, at no time a sufficient temperature for an efficient exhaust aftertreatment is reached [1]. The future Euro 6+ or certainly the expected new Euro 7 limit values will therefore only be achieved with suitable effective thermal heating, heat retention as well as DPF regeneration measures for the exhaust aftertreatment (EAT) system.

Today’s challenge is to almost comply with the emission limits 100% in Real Drive Emission (RDE) behavior, especially in the cold season, the so-called “cold city rides”, which are characterized by the fact that during the stop and go rides in the city at no time a sufficient temperature for an efficient exhaust aftertreatment is reached. The future Euro6+ or certainly the expected new Euro7 limit values will therefore only be achieved with suitable effective thermal heating, heat retention as well as regeneration measures for the exhaust aftertreatment (EAT) system.

The manufactures of internal combustion engines face currently a lot of challenges. Among these are the required drastic emission reductions of carbon dioxide (CO2) as well as harmful substances the most prominent. As a consequence of these harsh market conditions solutions that could cope with this framework are urgently needed. In this context the state of the art of synthetic fuels as an essential part of the energy system is discussed and how they could offer solutions.

In this work, a novel catalytic evaporator was tested in a single-cylinder Heavy-Duty Diesel engine in order to achieve low NOx and soot emissions as well as to control the combustion phase for homogeneous Low-Temperature Combustion (LTC). Conventionally, two fuels with different ignition properties are used to control the combustion phasing, however in this study only diesel is used. As a consequence of our presented approach, the ignition properties of the fuel vapour can be adjusted by changing the operating parameters of the catalytic evaporator.