Paper PS+AS+SE-MoM3
Plasma Catalysis for CO₂ and CH₄ Conversion at Atmospheric Pressure

Monday, October 30, 2017, 9:00 am, Room 21

The field of plasma-catalysis, i.e. combining a plasma process and a catalyst, either inside the plasma or in its post-discharge is gaining importance for the conversion of CO₂ and CH₄ mixtures. Indeed, the combination of plasma and catalysis could not only increase the conversion of these gases, but also orient the reaction(s) towards the synthesis of valuable molecules.

This paper will present first the main factors that influence the conversion and the energy efficiency for the reduction of CO₂ using an atmospheric pressure dielectric barrier discharge. Second, an alumina supported catalyst will be added between the electrodes and its effects on the conversion of pure CO₂, pure CH₄ and CO₂/CH₄ mixtures will be presented. Ni, Co, Cu have been tested, as well as various loadings of Ni.

The conversion is studied by atmospheric mass spectrometry, and the chemical identification of the end products was obtained either by mass spectrometry or gas chromatography.

It is shown that the frequency, the pulse mode, the dielectric nature and thickness strongly influence the conversion and energy efficiency of the reaction, whereas the residence time and the power injected into the discharge modify the conversion[1]. An increase in the Ni loadings leads to an increase in conversion of both CO₂ and CH₄. If CO and H₂, starting molecules for more complex organic chemistry, are always the main products of reaction, C2, C3 and C4 molecules, oxygenated or not are also detected. The effect of the nature of the catalyst on the relative amounts of these molecules is discussed.

[1] : A. Ozkan, A. Bogaerts, F. Reniers, J. Phys. D: Appl. Phys. 50 (2017) 084004, doi:10.1088/1361-6463/aa562c