Deactivation of copper-based catalysts in alcohol dehydrogenation

Abstract

The chapter investigates a series of Cu catalysts with alkaline earth metal oxide and chromia additives were investigated to elucidate the effect of additive on the activity and stability of Cu catalyst in alcohol dehydrogenation reaction. Copper-based catalysts are well-known active in alcohol dehydrogenation reaction. Chromium promoter could prolong the life and activity of copper catalyst as reported by several workers. In previous studies, the good dispersion of Cr2O3 promoter in unsupported catalyst helps to prevent sintering in both reduction and dehydrogenation processes. The dehydrogenation activity was found to be influenced by acid-base properties of additives combined with copper catalyst. The dehydrogenation of ethanol has been studied over a series of promoted copper catalysts. The results indicate that the activity and stability of Cr-promoted catalyst improved only in the case of copper promotion by minor amounts of Cr (Cr/Cu=1/40 molar ratio). The activity and stability of Cr-promoted catalysts decreased when the Cr/Cu molar ratio greater than 1/40. The Mg-promoted catalyst has a higher activity and stability than the unpromoted one; however, the Ca-, Sr-, and Ba-promoted catalysts are poor in stabilities than the unpromoted catalyst.