Oxidative dehydrogenation of ethane to ethylene: A promising CeO2-ZrO2-modified NiO-Al2O3/Ni-foam catalyst.

From macro- to nano-engineering of a promising CeO 2 -ZrO 2 -doped NiO-Al 2 O 3 /Ni-foam catalyst has been demonstrated for the oxidative dehydrogenation of ethane to ethylene (ODE), through facial wet chemical etching of a Ni-foam followed post modification with CeO 2 and ZrO 2 . The NiO-Al 2 O 3 /Ni-foam (denoted as NANF) achieved a high ethane conversion of 25.2% but with a very low ethylene selectivity of 43.1% at 450 °C. ZrO 2 -doping of the NANF led to a remarkable improvement in the ethylene selectivity but serious deterioration of activity while the CeO 2 -doping showed an opposite effect. Co-doping of the NANF using optimal amount of CeO 2 and ZrO 2 markedly promoted not only the activity but also the selectivity to ethylene. For example, over the 1CeO 2 -5ZrO 2 -NANF (CeO 2 :1 wt%, ZrO 2 :5 wt%) catalyst, a high ethane conversion of 40.3% was obtained with a 60.6% ethylene selectivity for a feed gas of C 2 H 6 /O 2 /N 2 = 1/1/8 at 500 °C and a gas hourly space velocity of 18,000 cm 3 g −1 h −1 , corresponding to a high ethylene productivity of 510 g Ethylene kg cat −1 h −1 . In nature, co-doping with CeO 2 and ZrO 2 synergistically tamed the NiO for selective H-abstraction of the ethane molecules other than over oxidation of them. [ABSTRACT FROM AUTHOR]