Catalytic amination of diethylene glycol with tertiarybutylamine over Ni–Al2O3 catalysts with different Ni/Al ratios

Abstract

The catalytic amination of diethylene glycol (DEG) with tertiarybutylamine (TBA) to tertiarybutylaminoethoxyethanol (TBEE) was investigated on Ni–Al₂O₃ heterogeneous catalysts that were prepared using the co-precipitation method. The catalytic performances of these Ni–Al₂O₃ catalysts were considerably influenced by the Ni/Al ratios as well as the calcination temperature and reduction temperature of the catalysts. The catalyst with a Ni/Al ratio of 1 : 1 that was calcined at 450 °C (NiAl-1.0-450), and reduced at 550 °C, exhibited a high activity and selectivity to TBEE. Based on the characterization, the activities were due to the action of the NiAl₂O₄ spinel in combination with NiO, which improved the stability of Ni(0), and the presence of both acidic and basic sites in the catalysts was also indispensable for this catalytic system.