CO2 Dissociation using the Versatile Atmospheric Dielectric Barrier Discharge Experiment (VADER)

• Main Authors: Michael Allen Lindon, Earl eScime
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2014-09-01
• Series: Frontiers in Physics
• Subjects: Plasma Physics; plasma chemistry; dielectric barrier discharge; CO2 reduction; plasma chemical model; Atmospheric plasmas
• Online Access: http://journal.frontiersin.org/Journal/10.3389/fphy.2014.00055/full

Dissociation of CO2 is investigated in an atmospheric pressure dielectric barrier discharge (DBD) with a simple, zero dimensional (0-D) chemical model and through experiment. The model predicts that the primary CO2 dissociation pathway within a DBD is electron impact dissociation and electron-vibrational excitation. The relaxation kinetics following dissociation are dominated by atomic oxygen chemistry. The experiments included investigating the energy efficiencies and dissociation rates of CO2 within a planar DBD, while the gas flow rate, voltage, gas composition, driving frequency, catalyst, and pulse modes were varied. Some of the VADER results include a maximum CO2 dissociation energy efficiency of 2.5 +/- 0.5%, a maximum CO$_2$ dissociation rate of 4 +/- 0.4*10^-6 mol CO2/s (5 +/- 0.5% percent dissociation), discovering that a resonant driving frequency of ~30 kHz, dependent on both applied voltage and breakdown voltage, is best for efficient CO2 dissociation and that TiO2, a photocatalyst, improved dissociation efficiencies by an average of 18% at driving frequencies above 5 kHz.