Exhaust manifold micro ammonia cracker for hydrogen engine

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Pochari Systems is pioneering the development of the world's most compact ammonia cracker to produce hydrogen on demand for hydrogen engine powered cars, trucks, and marine propulsion systems. This revolutionary technology uses 7% wt Ruthenium and 10% wt Cesium promoted CeO2 supported catalyst in a microchannel configuration. The cracker specifications are based on cutting-edge research by Engelbrecht and Chiuta (2018), Chiuta and Everson (2015, 2016), Di Carlo and Vecchione (2014), and Hill and Murciano (2014). With an activation energy as low as 75 kJ/mol of NH3, the cracker achieves high cesium promoter loadings on ceric oxide support, resulting in only 7.2 KW/kg of H2 reformed per hour. This allows for a remarkable 92% of the required energy for decomposition to be provided by exhaust heat from the diesel engine. The amount of ruthenium and cesium needed is minimal, requiring only 0.0017 kg and 0.005 kg respectively to reform 1 kg of hydrogen per hour at the desired efficiency and power density. This translates into a cost of just $200 for the raw materials of the catalyst and promoter based on current market prices for a 2 kg/hr cracker, sufficient for a medium-sized vehicle. The cost of the cerium oxide support comprising 83% of the catalyst mass is negligible. Cesium reserves are estimated to be 84,000 tons, with Ruthenium reserves around 5,000 tons, allowing for the production of billions of medium-sized car crackers. Most of the cost of the cracker lies in manufacturing, not raw materials. The manufacturing process involves forming tiny stainless steel microchannels from a solid block using wire electrical discharge machining. Washcoating and packing of the catalyst inside these tiny grooves complete the manufacturing process of a microreactor. Microreactor technology can be considered relatively simple compared to battery manufacturing as an example. The only complexities arise from the extremely small dimensions, which require elaborate and costly machinery to fabricate. These small dimensions found in microreactors (as little as 0.15 mm x 0.25 mm) necessitate the use of expensive and sophisticated equipment for fabrication. Nonetheless, the cost of the cracker will be approximately $1,000-1,500 per kg-hour of capacity at high production volumes, with material costs accounting for 15-20% of the total. The ammonia cracker is strategically located on the exhaust manifold for closed-cycle hydrogen diesel engines, utilizing engine exhaust heat to supply 92% of the cracker's energy needs. Oxy-hydrogen combustion provides the balance. The volume of the ammonia cracker for 20 kg/hr, sufficient for a large class-8 semi-truck at full power, is only 20 liters and weighs less than 10 kg. The cracker is designed in a modular fashion, consisting of multiple microchannels inside each housing module. Each module is placed directly outside of each exhaust outlet on the cylinder head, allowing hot exhaust gas to pass directly into the microchannels before cooling down. This enables heating the catalyst bed to provide the necessary activation energy. The modules are connected to four rails, supplying both gaseous ammonia and reform gas to the purifier. Reactor Type: Micro-channel stainless steel Catalyst: 7% wt Ru 10% wt Cs promoted on CeO2 Ru Catalyst required per Kg hour H2 reformed: 0.001 kg Ce Catalyst promoter per Kg hour H2 reformed: 0.005 kg Gravimetric density: 0.50 kg/kg H2-hr Volumetric density: 1 L/kg H2-hr Energy consumption: 6 kw/kg H2-hr Percent of reforming energy from exhaust heat: 92% Conversion rate: 99.8% Operating temperature: 500 °C Additional hydrogen consumed for dissociation: 0%, only during startup. Ammonia equivalent hydrogen density: 113 kg/m3 Ammonia consumption: 6 kg liquid NH3/kg H2-hr Startup time: 10 minutes Cracker cost: $1,000/kg-hr capacity Ruthenium cost: $8,000/kg Cesium cost: $30,000/kg