| Summary: | Bimetallic Pt-Co catalysts derived from cobalt aluminate spinel were investigated in the liquid-phase water–gas shift (WGS) reaction and CO hydrogenation. Liquid-phase WGS is a key reaction in the aqueous-phase reforming (APR) of polyols; thus, WGS activity is essential to formulate good APR catalysts. In this work, catalysts with different Pt/Co molar ratios were synthesized together with a reference Pt/alumina. All the synthesized catalysts were characterized by various techniques in order to gain knowledge on their structural and surface characteristics. WGS activity was tested with a feedstream of CO/H<sub>2</sub>O = 1/15 (space-time of 76.8 kg<sub>cat</sub>·s/mol<sub>CO</sub>), isothermal operation at 260 °C and 50 bar, for 10 TOS. Bimetallic Pt-Co catalysts showed improved activity in liquid-phase WGS in comparison to bare Co or Pt catalysts, which was ascribed to the synergistic effect. Despite being subjected to an increased hydrogen concentration in the feedstream (H<sub>2</sub>/CO between 0 and 12/3), these catalysts maintained a preferential selectivity towards WGS activity. In addition, the effect of temperature (220–260 °C) and pressure (25–50 bar) was investigated over a catalyst with 0.3Pt/CoAl. CO conversion and CO<sub>2</sub> yield were more sensitive to temperature, while a higher pressure favored methane production. The measured activation energy in the 220–260 °C temperature range was 51.5 kJ/mol.
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