Highly stable Co/CeO2 catalyst for high-temperature water-gas shift reaction using a CeO2 support with an optimized precipitant ratio

We report hydrogen production from waste through waste gasification and the water-gas shift reaction using highly stable Co/CeO2 catalysts. Here, careful control of the KOH:K2CO3 precipitant ratio during CeO2 support synthesis yielded highly active and stable Co/CeO2 catalysts. Crucially, the precipitant ratio affects the Co dispersion, oxygen vacancies, crystallinity, and Co-CeO2 interactions, and the Co dispersion increases with increase in KOH content. Further, the oxygen storage capacity improves at the optimal KOH:K2CO3 ratio. In addition, the Co-CeO2 interaction is enhanced when catalysts are synthesized using CeO2 with a large amount of K2CO3. All prepared Co/CeO2 catalysts show high CO conversion, even at extremely high gas hourly space velocities: the Co/CeO2 (lambda = 2:1 and 1:1.5) catalysts exhibit stable performance because of robust Co-CeO2 interactions, high oxygen storage capacities, and effective Co dispersions. These findings aid hydrogen production from waste and CeO2 support design for various catalytic reactions.