TY - JOUR

T1 - Design of Ni-based catalysts supported over binary La-Ce oxides: Influence of La/Ce ratio on the catalytic performances in DRM

AU - Grabchenko, M.

AU - Pantaleo, G.

AU - Puleo, F.

AU - Kharlamova, T. S.

AU - Zaikovskii, V. I.

AU - Vodyankina, O.

AU - Liotta, L. F.

N1 - Funding Information: This work was supported by Russian Foundation, Russia (project ID 19-73-30026 ), except for BET, XRD, TGA and H2-TPR analyses that were supported by the Project PON (2015-2020) Energie per l’Ambiente - Tecnologie e processi per l’Abbattimento di inquinanti e la bonifica di siti contaminati con Recupero di mAterie prime e produzioNe di energia TOtally green ( TARANTO )( ARS01_00637 ), Italy. The authors greatly acknowledge F. Giordano (ISMN-CNR, Italy) for XRD analyses. Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/12/15

Y1 - 2021/12/15

N2 - CeO2 and binary La2O3-CeO2 oxides, with different La/Ce atomic ratios (1:4; 1:1; 4:1), were synthesized using sol-gel method in the presence of citric acid in ammonia solution, at pH~9, and Ni (10 wt%) was added by wetness impregnation method. The physical-chemical properties, catalytic activity and long-run stability of the prepared catalysts were evaluated in DRM reaction. Characterizations of both fresh and spent catalysts were carried out using low-temperature N2 adsorption, XRD, TGA, TPR, Raman and TEM analyses. The DRM gradient catalytic tests performed in the range of 400–800 °C revealed higher catalytic conversions for Ni/La2O3-CeO2 catalysts, especially for those with La/Ce ratio 1:4 and 1:1. The stable conversions of CH4 and CO2 (long run at 650 °C for 24 h) registered for such Ni/La2O3-CeO2 catalysts were attributed to the presence of small Ni crystallites. During long run tests, Ni/La2O3-CeO2 catalysts, with La/Ce atomic ratios 1:4 and 1:1, formed the same types of carbon, both as filaments and layered carbon with graphene structure, but their catalytic activity was retained. Ni/CeO2 showed the smallest content of carbon, however, exhibited lower CH4 and CO2 conversions in comparison with the Ni-La2O3-CeO2 systems, due to the presence of big Ni particles with sizes of up to 0.5 µm.

AB - CeO2 and binary La2O3-CeO2 oxides, with different La/Ce atomic ratios (1:4; 1:1; 4:1), were synthesized using sol-gel method in the presence of citric acid in ammonia solution, at pH~9, and Ni (10 wt%) was added by wetness impregnation method. The physical-chemical properties, catalytic activity and long-run stability of the prepared catalysts were evaluated in DRM reaction. Characterizations of both fresh and spent catalysts were carried out using low-temperature N2 adsorption, XRD, TGA, TPR, Raman and TEM analyses. The DRM gradient catalytic tests performed in the range of 400–800 °C revealed higher catalytic conversions for Ni/La2O3-CeO2 catalysts, especially for those with La/Ce ratio 1:4 and 1:1. The stable conversions of CH4 and CO2 (long run at 650 °C for 24 h) registered for such Ni/La2O3-CeO2 catalysts were attributed to the presence of small Ni crystallites. During long run tests, Ni/La2O3-CeO2 catalysts, with La/Ce atomic ratios 1:4 and 1:1, formed the same types of carbon, both as filaments and layered carbon with graphene structure, but their catalytic activity was retained. Ni/CeO2 showed the smallest content of carbon, however, exhibited lower CH4 and CO2 conversions in comparison with the Ni-La2O3-CeO2 systems, due to the presence of big Ni particles with sizes of up to 0.5 µm.

KW - Dry reforming of methane (DRM)

KW - LaO-CeO binary oxide, solid solution

KW - Ni-based catalysts

UR - http://www.scopus.com/inward/record.url?scp=85111007876&partnerID=8YFLogxK

U2 - 10.1016/j.cattod.2021.07.012

DO - 10.1016/j.cattod.2021.07.012

M3 - Article

AN - SCOPUS:85111007876

VL - 382

SP - 71

EP - 81

JO - Catalysis Today

JF - Catalysis Today

SN - 0920-5861

ER -