Nickel, copper, and cobalt were templated on zeolite mordenite (MOR) by ion exchange in mono, bi, and trimetallic form for the deoxygenation of acetic acid. Metal loadings were below 3 wt.% for all catalysts. Catalysts were characterized by cryogenic argon physisorption, temperature programmed reduction (TPR) and desorption of ammonia (TPD), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Deoxygenation of acetic acid was studied due to its abundance in pyrolysis aqueous phase streams. Activity for reaction pathways including decarboxylation (DCO), decarbonylation (DCN), and hydrodeoxygenation (HDO) were tracked temporally. A key finding was the vital nature of Ni in activating acetic acid while dissociating H2 at 400 °C. Bimetallic Ni-Co had greater activity for HDO at 400 °C, due to the suppression of DCN. Acetic acid conversion was quasi-linearly related to the Ni content across the mono/bi/trimetallic catalysts at 400 °C. Cryogenic argon isotherms revealed that the metal sites were preferentially located at the side pocket on MOR, in agreement with previous studies of Cu-MOR. Catalyst stability, reducibility, and acidity were tracked using TGA, TPR, and TPD, respectively. Spent catalysts showed agglomeration of metal species, observed by TEM. The long-term stability of Ni-MOR was assessed under differential and integral conditions at 460 °C. Integral operation resulted conversion of acetic acid for at least 70 h greater than 95 % selecting for DCN and HDO pathways. Differential conditions revealed a stability of 23 h with good recyclability. Bimetallic Co-Ni stabilized in a co-localized morphology due to non-reducible Co species anchoring mobile Ni particles.
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