Electrospun nanofibrous Ni/LaAlO3 catalysts for syngas production by high temperature methane partial oxidation

Abstract

Ni/Al2O3 catalysts have been widely used for methane reforming while the formation of NiAl2O4 with low reducibility reduces catalyst efficiency. La2O3 was used to promote the catalytic activity of Ni/Al2O3 catalysts through improving Ni dispersion. LaAlO3 perovskite showed catalytic activity in methane coupling and also used as a catalyst support for methane reforming. This study systematically investigated the effect of La2O3 addition into Ni/Al2O3 catalysts and found the formation of LaAlO3 perovskite played an important role, which requires high crystallization temperatures. The thermally-stable structure of nanofibrous catalysts was employed to develop high-performance Ni/LaAlO3 catalysts. High calcination temperature resulted in the enhanced crystallinity of LaAlO3 perovskite, improved Ni reducibility and strengthened catalyst/support interaction, which contributed to high catalytic performance during methane partial oxidation. The Ni/LaAlO3 catalyst calcined at 1100 °C generated a CH4 conversion of 91.2% during methane partial oxidation with H2 and CO selectivities of 95.5% and 92.4%, respectively. It is because La2O3 addition into Ni/Al2O3 promoted Ni reduction via forming LaAlO3. Therefore, an efficient and thermally-stable fibrous Ni/LaAlO3 catalyst has been developed for high temperature methane partial oxidation.