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Catalyst D
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Figure 5 Extract of a customer project studying the performance and stability of four catalysts at various process conditions (screening of temperature, GHSV, and feed composition at elevated pressure using hte’s advanced high throughput technology)
active at 450°C, cracking 1-11% of NH₃. It was even possible to resolve NH₃ conversion in a range of 0.4-1.4%. For example, for catalyst B, >97% NH₃ conversion was reached around 650-750°C, depending on the catalyst material and GHSV. Moreover, the catalytic performance was investigated as a function of NH3 feed concentration, resulting in a declining trend at lower values, providing insight into the performance of a lower zone of the catalyst bed or even recycle operation. Summary The feasibility of hte’s flexible 16-fold high throughput unit for high-pressure NH₃ cracking was successfully demonstrated. Unit validation was carried out using a Fe-based catalyst under process conditions up to 750°C, 50 barg, and 200,000 h -1 . The established feed and analytics workflow allowed reliable dosing and full recovery of NH₃ next to 5,000 ppm of H₂O, building the basis for evaluating the influence of water on catalyst performance and stability in follow-up customer projects. Catalytic activity was resolved precisely at <1% or close to full NH₃ conversion in the absence of significant blind conversion from the reactor material itself, enabling the generation of kinetic data sets for NH₃ cracking. Smart experiment design allowed the screening of 39 parameters in only two weeks while performing a stability test at constant temperature in parallel. Subsequent customer projects aimed at ranking four different commercial catalysts, achieving >97% NH₃ conversion at 650°C under industrially relevant
conditions, demonstrating state-of-the-art properties. Further research on commercialising NH₃ cracking is required regarding catalyst stability under different process conditions and performance as a function of TOS. hte’s integrated workflow solutions enable accelerated ageing test protocols and parallel difference testing. The root cause and rate of deactivation need to be explored to define measures to achieve constant conversion. This innovative approach to NH₃ cracking process optimisation not only accelerates catalyst assessment but also holds promise for advancing the efficient production of H₂ from NH₃ at elevated pressure. By enabling rapid testing of diverse catalysts and process conditions, this high throughput technology contributes to the realisation of energy-efficient NH₃ cracking processes, essential for addressing the increasing demand for H₂ in various regions. Current technology developments at hte address flexible high- temperature bench-scale units for operation at 1,000°C and up to 30 barg, as well as larger reactors to allow testing of extrudates and measurement of temperature profiles along the catalyst bed.
VIEW REFERENCES
Benjamin Mutz Benjamin.Mutz@hte-company.de Robert Baumgarten Robert.Baumgarten@hte-company.de
www.decarbonisationtechnology.com
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