Nanocomposites and nanomaterials
Plasma-catalytic conversion of CO2-CH4 over metal-oxide catalysts
Samoilenko D. E., Kyriienko P. I.
L.V. Pisarzhevskii Institute of Physical Chemistry of the NAS of Ukraine.
Prospect Nauky, 31, Kyiv-03039, Ukraine.
E-mail: d.samoylenko96@gmail.com

Promising way to attract carbon dioxide into the production process may be combination of cold plasma and catalyst. Plasma will activate CO2 at relatively low temperatures (about 373 K) and interaction of activated reagents with the formation of target products will occur on the surface of catalyst. Today use of plasma in the process of dry methane reforming was investigated [1]. The same plasma-catalytic approach is of high interest for valuable oxygenates production (alcohols, aldehydes and carboxylic acids) from CO2-CH4.
Plasma-catalytic conversion of a CO2-CH4 mixture at atmospheric pressure was performed on next metal-oxide catalysts: Al2O3, MgO, MgO-Al2O3, CuО-ZnO/Al2O3, ZnO/Al2O3, Ni-La/Al2O3. Samples are presented in ascending order of conversion, the maximum conversion was achieved over Ni-La/Al2O3 sample: 27% by CH4 and 17% by CO2. Catalyst electron structure defines conversion and yield of C-C coupling compounds (ethane, ethyl acetate, ethanol), which are increasing in the row dielectric-semiconductor-conductor. Selectivity of C-C coupling products is defined by acid-base catalyst characteristics. Maximum yield of ethanol (5%) was achieved over MgO-Al2O3 sample, which is characterized by the highest concentration of base sites (Cb=0.30 mmol CO2/g).  
Thus, the combination of cold plasma and the catalyst with specific acid-base characteristics and electron structure provides conversion of reagents into valuable C-C coupling products and syngas.

1.	Andersen J., Christensen J., Østberg M., Bogaerts A., Jensen A.D. Plasma-catalytic dry reforming of methane: Screening of catalytic materials in a coaxial packed-bed DBD reactor// Chemical Engineering Journal.-2020.-397.-P. 125519.