Nanocomposites and nanomaterials

Catalytic properties of bimetallic catalysts supported on nanocarbon in the reaction of CO2 hydrogenation 
G. Tsapyuk1, А. Dyachenko1, S. Gaidai1, T. Zakharova1, O. Ishchenko1, G. Ilnytska2
1Taras Shevchenko National University of Kyiv,
64/13 Volodymyrs’ka Str, Kyiv, 01601, Ukraine
E-mail: tsapyuk@ukr.net
2V.Bakul Institut for Superhard materials of the NAS of Ukraine
2, Avtozavodskaya Str., Kiev, 04074, Ukraine

The catalytic properties of bimetallic catalysts supported on nanocarbon were investigated in the reaction of CO2 hydrogenation to methane. Previous studies [1, 2] have shown the effectiveness of massive Co-Fe and Ni-Fe materials for CH4 production. In this abstract, investigation of the catalytic properties of nanosized Co-Fe/carbon and Ni-Fe/carbon materials is presented. The samples of bimetallic catalysts supported on nanosized-carbon were prepared by co-precipitation with metal nitrate solution and further reduction of metal oxide precursors by hydrogen (50 vol% H2 in He). 
The data of specific surface and catalytic activity are presented in the table.
	Catalyst	Ssp, m2/g	CH4, yield, %	
			250 °C	300 °C	350°C	
1	20 wt% Ni80Fe20/carbon	190	10	100	100	
2	20 wt% Co93Fe7/carbon	190	58	96	100	
3	10 wt% Co93Fe7/carbon	240	1	41	83	
TPD MS investigations of the catalysts’ surface layer showed the presence of fragments with m/z 18, 28, 44 corresponded to H2O*, CO*, CO2* particles, relatively. TD profile of these particles has a smooth and symmetrical form. It is likely that these compounds are dissociated upon adsorption and desorb with second-order kinetics. It is reasonable to assume that, the reaction proceeds according to mechanism that proposes the dissociation of CO2 with further reduction of carbon species to methane.

1.	Zhludenko M., Dyachenko A., Bieda O., Gaidai S., Filonenko M., Ischenko O. Structure and catalytic properties of Co–Fe systems in the reaction of CO2 methanation // Acta Physica Polonica A. – 2018. - 133, N.4. -P.1084-1087.
2.	Meshkini Far R., Ishchenko O.V., Dyachenko A.G., Bieda O., Gaidai S., Lisnyak V. CO2 hydrogenation into CH4 over Ni–Fe catalysts // Functional Materials Letters. – 2018. - 11, N.3. - 1850057.