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
Consolato Rosmini, Monica Pazos Urrea, Enrico Tusini, Sylvio Indris, Daniela Kovacheva, Daniela Karashanova, Hristo Kolev, Anna Zimina, Jan‐Dierk Grunwaldt, Magnus Rønning, Momtchil Dimitrov, Margarita Popova
Abstract
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 Ni x Sn y /Ce(Zr)O 2 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 H 2 -yields while still minimizing methanation due to the alkali-induced process of Cannizzaro disproportionation of EG into glycolic acid with subsequent reforming thereof. • Nickel and Ni x Sn y 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 H 2 yield. • Synergistically, Sn content tunes Ni reactivity and hence H 2 and CH 4 selectivities.