Unveiling the synergistic effects of pH and Sn content for tuning the catalytic performance of Ni0/NixSny intermetallic compounds dispersed on Ce-Zr mixed oxides in the aqueous phase reforming of ethylene glycol

• Published in: Applied catalysis. B, Environmental Vol. 350; p. 123904
• Main Authors: Rosmini, Consolato, Urrea, Monica Pazos, Tusini, Enrico, Indris, Sylvio, Kovacheva, Daniela, Karashanova, Daniela, Kolev, Hristo, Zimina, Anna, Grunwaldt, Jan-Dierk, Rønning, Magnus, Dimitrov, Momtchil, Popova, Margarita
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05-08-2024
• Subjects: Ethylene Glycol aqueous phase reforming; H2 and glycolic acid production; Induced Cannizzaro reaction; Initial alkaline pH; Ni-Sn intermetallic compounds; Initial alkaline pH; Induced Cannizzaro reaction; H2 and glycolic acid production; Ethylene Glycol aqueous phase reforming; Ni-Sn intermetallic compounds
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2024.123904

The product distribution in aqueous phase reforming (APR) of polyols is closely tied to the catalytically induced feed cleavage mechanism. Strategic variations in catalyst composition and synergistic effects prompted by reaction conditions, such as pH, can be utilized to tune the product distribution of both liquid and gaseous phases. This study aimed to compare the physicochemical properties of various NixSny/Ce(Zr)O2 catalysts and their performance in batch tests during the APR of a 6%wt. ethylene glycol (EG) solution under both neutral and alkaline conditions. The results show that the progressive addition of tin strongly tunes the activity of the catalysts and the nickel-induced methanation reaction under neutral conditions, albeit decreasing feed conversions. In synergy with tin tuning, the alkaline environment boosts the process by increasing conversions and H2-yields while still minimizing methanation due to the alkali-induced process of Cannizzaro disproportionation of EG into glycolic acid with subsequent reforming thereof.
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•Nickel and NixSny on ceria-zirconia were tested for APR of ethylene glycol (EG).•Influence of initial pH and Sn content on the catalytic performance was studied.•Just at alkaline pH a disproportionation of the EG into glycolic acid was observed.•At high pH, reaction pathway significantly increases feed conversion and H2 yield.•Synergistically, Sn content tunes Ni reactivity and hence H2 and CH4 selectivities.