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Abstract Direct non‐oxidative methane conversion (DNMC) has been recognized as a single‐step technology that directly converts methane into olefins and higher hydrocarbons. High reaction temperature and low catalyst durability, resulting from the endothermic reaction and coke deposition, are two main challenges. We show that a millisecond catalytic wall reactor enables stable methane conversion, C2+selectivity, coke yield, and long‐term durability. These effects originate from initiation of the DNMC on a reactor wall and maintenance of the reaction by gas‐phase chemistry within the reactor compartment. The results obtained under various temperatures and gas flow rates form a basis for optimizing the process towards lighter C2or heavier aromatic products. A process simulation was done by Aspen Plus to understand the practical implications of this reactor in DNMC. High carbon and thermal efficiencies and low cost of the reactor materials are realized, indicating the technoeconomic viability of this DNMC technology.
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This content will become publicly available on December 25, 2025
Modeling and Optimization of Methane Dehydroaromatization Coupled with Chemical Looping and Temperature Swing Adsorption
Natural gas at remote locations would greatly benefit from on-site processing using modular technologies such as dehydroaromatization (DHA). This work models an intensified DHA process to increase product yield and methane conversion by coupling the reactor with a chemical looping unit that effectively separates hydrogen through a redox cycle and a temperature swing adsorption process to remove the aromatics and water and recycle unconverted methane. We postulate dynamic models and steady-state surrogate models to analyze and optimize the production of the aromatic product. The optimum methane conversion of 48% and the aromatic yield of 42% occur at a recycle ratio of 0.47 and a reactor temperature of 725 degrees C.
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- Award ID(s):
- 1803246
- PAR ID:
- 10571025
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Industrial & Engineering Chemistry Research
- Volume:
- 63
- Issue:
- 51
- ISSN:
- 0888-5885
- Page Range / eLocation ID:
- 22298 to 22309
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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