NiFe and CoFe nanocatalysts supported on highly dispersed alumina-silica: Structure, surface properties, and performance in CO 2 methanation.

Autor: Dyachenko A; Institute of Physical Chemistry, PAS, Warsaw, Poland; Chuiko Institute of Surface Chemistry, NASU, Kyiv, Ukraine., Ischenko O; Taras Shevchenko National University of Kyiv, Kyiv, Ukraine., Pryhunova O; Taras Shevchenko National University of Kyiv, Kyiv, Ukraine., Gaidai S; Taras Shevchenko National University of Kyiv, Kyiv, Ukraine., Diyuk V; Taras Shevchenko National University of Kyiv, Kyiv, Ukraine., Goncharuk O; National Technical University of Ukraine 'Igor Sikorsky Kyiv Polytechnic Institute', Kyiv, Ukraine., Mischanchuk O; Chuiko Institute of Surface Chemistry, NASU, Kyiv, Ukraine., Bonarowska M; Institute of Physical Chemistry, PAS, Warsaw, Poland., Nikiforow K; Institute of Physical Chemistry, PAS, Warsaw, Poland., Kaszkur Z; Institute of Physical Chemistry, PAS, Warsaw, Poland., Hołdyński M; Institute of Physical Chemistry, PAS, Warsaw, Poland., Lisnyak VV; Taras Shevchenko National University of Kyiv, Kyiv, Ukraine. Electronic address: lisnyak@univ.kiev.ua.
Jazyk: angličtina
Zdroj: Environmental research [Environ Res] 2024 Aug 15; Vol. 255, pp. 119203. Date of Electronic Publication: 2024 May 21.
DOI: 10.1016/j.envres.2024.119203
Abstrakt: The hydrogenation of CO 2 to CH 4 has gained considerable interest in terms of sustainable energy and environmental mitigation. In this regard, the present work aims to investigate the adsorptive concentration and CO 2 methanation performance over CoFe and NiFe bimetallic catalysts supported on fumed alumina-silica SA96 support at 170-450 °C and under atmospheric pressure. The catalysts were prepared by wet impregnation method, subjected to calcination and further reduced with hydrogen, and their performance in CO 2 methanation was investigated in a hydrogen-rich 2%CO 2 -55%H 2 -43%He gas mixture. In this study, we describe the crystal and mesoporous structures of the prepared catalysts by in-situ XRD and ex-situ nitrogen adsorption, evaluate the NiFe and CoFe metal surface states before and after catalysis by XPS, visualize the surface morphology by SEM, estimate the catalytic activity by gas chromatography, and investigate the adsorbed surface species, showing the presence of *HCOO/*HCO and *CO intermediates, determine two possible pathways of CH 4 formation on the studied catalysts by temperature-programmed desorption mass spectrometry, and correlate the structural and surface properties with high CO 2 conversions up to 100% and methanation selectivities up to 72%. The latter is related to changes in the elemental chemical states and surface composition of CoFe and NiFe nanocatalysts induced by treatment under reaction conditions, and the surface reconstruction during catalysis transfers the part of active 3d transition metals into the pores of the SA96 support. Our thorough characterization study with complementary techniques allowed us to conclude that this high activity is related to the formation of catalytically active Ni/Ni 3 Fe and Co/CoFeO x nanoscale crystallites under H 2 reduction and their maintenance under CO 2 methanation conditions. The successfully applied combination of CO 2 chemisorption and thermodesorption techniques demonstrates the ability to adsorb the CO 2 molecules by supported NiFe and CoFe nanocatalysts and the pure alumina-silica SA96 support.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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