TY - JOUR

T1 - Effect of preparation conditions of nanocrystalline Pd/MgO catalysts on their performance in selective hydrogenation of acetylene

AU - Ilyina, Ekaterina V.

AU - Yurpalova, Daria V.

AU - Shlyapin, Dmitry A.

AU - Veselov, Grigory B.

AU - Shivtsov, Danil M.

AU - Stoyanovskii, Vladimir O.

AU - Bukhtiyarov, Andrey V.

AU - Vedyagin, Aleksey A.

N1 - This study was supported by the Ministry of Science and Higher Education of the Russian Federation within the governmental order for Boreskov Institute of Catalysis (projects No's. FWUR-2024-0034 and FWUR-2024-0039).

PY - 2024

Y1 - 2024

N2 - In the present work, an alkoxide sol-gel method was applied to prepare Pd/MgO catalysts. The sol-gel procedure was followed by supercritical drying (aerogels) or conventional drying (xerogels) in a furnace. These materials were compared with the impregnated samples. The Pd loading was 1 wt% in all the cases. The as-prepared catalysts were characterized by a set of physicochemical methods. Both the type of the Pd precursor and the preparation route were found to affect the porous structure of the materials as well as the dispersion of the palladium particles and their localization over the MgO support. Both the xerogel and incipient wetness impregnation methods lead to a narrower pore size distribution in comparison to the aerogel technique. The most dispersed particles with an average size of ∼ 2.0–2.2 nm were observed for the samples prepared by xerogel and impregnation methods. In the case of aerogel-prepared samples, metallic palladium particles possess bimodal distribution with average diameters of 4.3 and 8.4 nm. The best catalytic performance in acetylene hydrogenation to ethylene (50 % acetylene conversion at 37 °C with selectivity ∼60 %) was observed for the Pd/MgO catalyst prepared via the aerogel route using [Pd(NH3)4](NO3)2. Compared to other samples, this material is characterized by relatively weak metal-support interactions and the availability of active sites for reactants, which ensures the kinetic mode of the hydrogenation reaction (Ea = 74.9 kJ/mol).

AB - In the present work, an alkoxide sol-gel method was applied to prepare Pd/MgO catalysts. The sol-gel procedure was followed by supercritical drying (aerogels) or conventional drying (xerogels) in a furnace. These materials were compared with the impregnated samples. The Pd loading was 1 wt% in all the cases. The as-prepared catalysts were characterized by a set of physicochemical methods. Both the type of the Pd precursor and the preparation route were found to affect the porous structure of the materials as well as the dispersion of the palladium particles and their localization over the MgO support. Both the xerogel and incipient wetness impregnation methods lead to a narrower pore size distribution in comparison to the aerogel technique. The most dispersed particles with an average size of ∼ 2.0–2.2 nm were observed for the samples prepared by xerogel and impregnation methods. In the case of aerogel-prepared samples, metallic palladium particles possess bimodal distribution with average diameters of 4.3 and 8.4 nm. The best catalytic performance in acetylene hydrogenation to ethylene (50 % acetylene conversion at 37 °C with selectivity ∼60 %) was observed for the Pd/MgO catalyst prepared via the aerogel route using [Pd(NH3)4](NO3)2. Compared to other samples, this material is characterized by relatively weak metal-support interactions and the availability of active sites for reactants, which ensures the kinetic mode of the hydrogenation reaction (Ea = 74.9 kJ/mol).

KW - Acetylene hydrogenation

KW - Aerogels

KW - Magnesium oxide

KW - Palladium nanoparticles

KW - Sol-gel synthesis

KW - Xerogels

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85190255362&origin=inward&txGid=cba3d93f8ebe1e55da888a7bc0d2f596

UR - https://www.mendeley.com/catalogue/ecc6d768-5aed-3add-9fff-1f852de61d45/

U2 - 10.1016/j.mcat.2024.114151

DO - 10.1016/j.mcat.2024.114151

M3 - Article

VL - 560

JO - Molecular Catalysis

JF - Molecular Catalysis

SN - 2468-8231

M1 - 114151

ER -