(591h) Development of a Zero-Carbon Methane Dehydroaromatization Process Design

There is a growing interest in converting natural gas to products with low or zero CO₂ emissions. Methane dehydroaromatization (MDA) has received significant attention in the field of catalysis as a promising route to convert natural gas into benzene during the past two decades. To date only a few process design and integration studies have been reported for this reaction with limited analysis of catalyst coking and regeneration and with incomplete techno-economic and CO₂ emissions analyses.

This work first establishes an integrated base case MDA process design, which embeds design options proposed in the literature, such as using part of the feedstock as fuel to drive the process, accounts for catalyst regeneration and all process CO₂ emissions. The process is then progressively transformed towards a zero-carbon process by exploring alternative hydrogen separations, exploring alternative catalyst regeneration options, energy integration and switching to hydrogen enriched fuels drawn downstream of the reactor. The alternative process designs explored and compared based on the economic performance criterion Internal Rate of Return (IRR) and based on specific process CO₂ emissions per methane feed. The developed designs drive down process CO₂ emissions at each step of design exploration with the final design achieving zero-carbon emissions. Each design is simulated using commercial process simulation software and economically analyzed.

The different designs will be explained together with their economic performance and overall CO2 emissions. The results indicate profitability for all developed designs with an IRR of 14% achieved by the zero-carbon process. Besides the zero-carbon process, a second very attractive low-carbon design allows to reduce the base case process emissions by 95% while maintaining the IRR at the 18% level observed for the base case. The presented work illustrates how integrated process design and integration can lead to significant emissions reduction with little or no economic performance deterioration.