Ethanol dehydrogenation over Cu catalysts promoted with Ni : stability control

NiCu alloyed catalysts are investigated for ethanol dehydrogenation. Seven Xwt%Ni-Ywt%Cu/Mg(Al)(Ni)(Cu)O-x catalysts, (X = 0.5 or 1, Y = 0, 5, 10 or 20) have been compared with a 10 wt%Cu/Mg(Al)(Cu)O-x benchmark. It was found that Ni promotion increases the turn-over frequency of a Cu-based catalyst. Two deactivation regimes were observed, i.e., a fast deactivation within the first hours on stream during which the acetaldehyde selectivity improved, followed by a slower deactivation. TPO and STEM indicated that surface carbon formation and sintering were likely at the origin of respectively the first and second deactivation regime. On the best performing catalyst, i.e., 1 wt%Ni-10 wt%Cu/Mg(Al)(Ni)(Cu)O-x, no fast deactivation regime was observed and the lowest amount of carbon was produced. Upon feeding 30 wt%H2O/ethanol, the activity of all NiCu catalysts increased. Overall, 1 wt%Ni-10 wt%Cu/Mg(Al)(Ni)(Cu)O-x was the best performing catalyst with a TOF of 0.09s(-1) and an acetaldehyde selectivity of 99 %.

Jaar van publicatie:2020

Toegankelijkheid:Closed