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arXiv · 2211.00592

High-Pressure CO$_2$ Dissociation with Nanosecond Pulsed Discharges

Erwan pannier·Taemin Yong·Christophe Laux·Mark A. Cappelli
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Abstract

The efficiency of the conversion of CO$_2$ into CO with nanosecond repetitively pulsed discharges (NRP) is investigated in a high pressure batch reactor. Stable discharges are obtained at up to 12~bar. By-products of CO$_2$ splitting are measured with gas chromatography. The energy efficiency is determined for a range of processing times, pulse energy, and fill pressures. The energy efficiency is found to be approximately 20% and is only weakly sensitive to the plasma operating parameters, i.e., the extent of CO$_2$ conversion is almost linearly-dependent on the specific energy input. A conversion rate of up to 14% is achieved with an energy efficiency of 23%. For long processing times, a drop in efficiency is observed, due to the increasing significance of recombination reactions, as described by a macroscopic kinetic mechanism. Reaction pathways that are believed to play an important role in nanosecond pulsed discharges are discussed. It appears that vibrational excitation does not play a significant role in CO$_2$ conversion in these types of short-pulse discharge. Results also draw attention to the relative importance of two particular electronic excitation reactions.

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Erwan pannier, Taemin Yong, Christophe Laux, Mark A. Cappelli. 2022-10-29. High-Pressure CO$_2$ Dissociation with Nanosecond Pulsed Discharges. https://arxiv.org/abs/2211.00592

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