Dehydrogenation of Ethane Using Concentrating Solar Power

Ethylene, the world’s highest volume petrochemical, is produced using steam cracking of alkanes. This reaction is carried out at high temperatures ( >900^oC) by the burning of natural gas which produces around a metric ton of CO₂ per ton of ethylene produced and requires energy inputs of up to 16 GJ per ton of produced ethylene [1-2]. In industry this heat and energy transfer occurs by the combustion of natural gas or other fossil fuels. The purpose of this research is to develop an alternative process that uses solar heating of a catalytic reactor to drive the dehydrogenation of ethane to ethylene. As has been previously demonstrated, ethane dehydrogenation can be performed at temperatures reachable by concentrated solar technologies (CST) [2]. The challenge then becomes what to do about the inherent intermittence of solar power. Thermal storage media already used in CST applications provide an intriguing solution. Quartz tubes were filled with solid thermal storage media, then heated to temperatures required for the dehydrogenation reaction while an ethane-carrier gas mixture was flowed through the system. Quartz tubes were chosen as they have been previously demonstrated to achieve ethylene yields of up to 68% using the open tube setup [2-4] This experimental setup demonstrated that thermal storage media can transfer sufficient energy to drive the dehydrogenation of ethane. This study also demonstrates that the packed tube is more efficient than an empty quartz tube in transferring heat to the reactant gases.

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• R. Riley, A. De, I. L. Ibarra, A. K. Datye, and S. S. Chou, “Achieving high ethylene yield in non-oxidative ethane dehydrogenation,” Applied Catalysis A: General, vol. 624, pp. 118309–118309, Aug. 2021, doi: https://doi.org/10.1016/j.apcata.2021.118309.
• Scott A. Steinmetz, Andrew T. DeLaRiva, Christopher Riley, Paul Schrader, Abhaya Datye, Erik D. Spoerke, and Christopher J. Kliewer The Journal of Physical Chemistry C 2022 126 (6), 3054-3059, DOI: 10.1021/acs.jpcc.1c09955
• Efficient Low-temperature, Catalyst free Dehydrogenation Of Alkanes, by C. R. Riley. (2022, Jul. 14). US20230037379A1. [Online]. Available: https://ppubs.uspto.gov/pubwebapp/