High sustainability of Cu–Al–Ox catalysts against daily start-up and shut-down (DSS)-like operation in the water–gas shift reaction

Coprecipitated-Cu–Al–Ox catalyst calcined at 823 K (CP-823) showed higher activity and sustainability than a commercial Cu/ZnO/Al2O3 catalyst even after 50 cycles of the daily start-up and shut-down (DSS)-like operation in the water–gas shift reaction. The high, stable activity of CP-823 is caused by the formation of highly dispersed and stable Cu metal. A boehmite phase formed “in situ” during the DSS operation has an important role in inhibition of aggregation of Cu metal particles.