| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS-ThA |
| Session: | Plasma Chemistry and Plasma Surface Interactions |
| Presenter: | Ramses Snoeckx, University of Antwerp, Belgium |
| Authors: | A. Bogaerts, University of Antwerp, Belgium Snoeckx, University of Antwerp, Belgium |
| Correspondent: | Click to Email |
Plasma-based CO2 conversion is gaining increasing interest. We try to obtain better insight in the underlying mechanisms by experiments and computer modeling. Our experiments are carried out in a (packed bed) DBD and in a vortex-flow gliding arc (GA) reactor, focusing mainly on the conversion and energy efficiency at different conditions and reactor setups. Our model calculations focus especially on the detailed plasma chemistry in a DBD, GA and microwave (MW) plasma, for pure CO2 as well as mixtures of CO2 with N2, CH4 and H2O. For this purpose, we make use of a zero-dimensional chemical kinetics model.
When studying the plasma chemistry in pure CO2, we focus especially on the the role of vibrationally excited CO2 levels, which are the key species for enhanced energy efficiency of the CO2 conversion [1].
We have also studied the plasma chemistry in CO2/CH4 [2,3] and in CO2/H2O [4] mixtures in a DBD reactor, for producing value-added chemicals. The main products formed are a mixture of H2 and CO, or syngas, with a tuneable H2/CO ratio depending on the gas mixing ratio. The production of oxygenated compounds is very limited. A detailed chemical kinetics analysis allows to elucidate the different pathways leading to the observed results, and to propose solutions on how to improve the formation of value-added products.
Finally, we also studied the plasma chemistry in a CO2/N2 mixture, both in a DBD [5] and in a MW [6] plasma, to investigate the effect of this important impurity in effluent gases on the CO2 conversion, energy efficiency and product formation. Our model and experiments reveal that N2O and NOx compounds are produced in the range of several 100 ppm. The reaction pathways for the formation of these compounds are again explained based on a kinetic analysis, which allows proposing solutions on how to prevent the formation of these harmful compounds.
References
1. T. Kozák, A. Bogaerts, Plasma Sources Sci. Technol. 23 (2014) 045004.
2. R. Snoeckx, R. Aerts, X. Tu, A. Bogaerts, J. Phys. Chem. C 117 (2013) 4957-4970.
3. R. Snoeckx, Y.X. Zeng, X. Tu, A. Bogaerts, RSC Advances 5 (2015) 29799-29808.
4. R. Snoeckx, A. Ozkan, F. Reniers and A. Bogaerts, paper in preparation.
5. S. Heijkers, R. Snoeckx, T. Kozák, T. Silva, T. Godfroid, N. Britun, R. Snyders and A. Bogaerts, J. Phys. Chem. C 119 (2015) 12815-12828.
6. R. Snoeckx, S. Heijkers, K. Van Wesenbeeck, S. Lenaerts and A. Bogaerts, Energy & Environm. Sci. 9 (2016) 999-1011