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Sibunit-Supported Mono- and Bimetallic Catalysts Used in Aqueous-Phase Reforming of Xylitol.

ABSTRACT: Carbon-supported mono- and bimetallic catalysts prepared via incipient wetness impregnation were systematically studied in aqueous-phase reforming (APR) of xylitol aiming at hydrogen production from biomass. The catalytic performance of several VIII group metals and their combinations, such as Pt, Ni, Pt-Ni, Re, Pt-Re, Ru, Pt-Ru, and Pt-Co, was compared for xylitol APR in a fixed-bed reactor at 225 °C and 29.7 bar (N2). Ni/C, Ru/C, and Re/C catalysts displayed significantly lower activity compared to others. Activity and selectivity to H2 of bimetallic Pt-Ni/C, Pt-Co/C, and Pt-Ru/C catalysts were close to that of Pt/C. Pt-Re/C catalyst showed an outstanding performance which was accompanied by a shift of the reaction pathways to the alkane formation and thereby lower hydrogen selectivity. Addition of the second metal to Pt was not found to be beneficial for hydrogen production, thus leaving Pt/C as the optimum carbon-supported catalyst.

SUBMITTER: Godina LI

PROVIDER: S-EPMC6156104 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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