The partial oxidation of methane to syngas over the nickel-modified hexaaluminate catalysts BaNiyAl12-yO19-δ

A series of Ni-modified hexaaluminates BaNiyAl12-yO19-delta (y = 0.3, 0.6, 0.9, and 1.0) were prepared by decomposition of nitrates and calcination at high temperature. The crystalline structure and catalytic properties for partial oxidation of methane to synthesis gas were investigated by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) and TG techniques. Over all compositions of the systems, the reduced Ni-modified hexaaluminates BaNiyAl12-yO19-delta exhibit significant catalytic activity and stability for the partial oxidation of methane to syngas, with 92% of CH4 conversion and 95% CO selectivity at 850degreesC. After 100h of time on stream, no loss of nickel was detected and carbon deposition is nearly negligible. Both advantageous results were attributed to the strong interaction between nickel and its neighboring atoms in hexaaluminates. (C) 2002 Published by Elsevier Science B.V.