Carbon dioxide reforming of methane to synthesis gas over hexaaluminate ANiAl 11 O 19-delta (A = Ca, Sr, Ba and La) catalysts

Abstract

A series of A‐modified hexaaluminates, ANiAl11O19-δ (A = Ca, Sr, Ba and La) as new catalysts for carbon dioxide reforming of methane to synthesis gas, were prepared by decomposition of nitrates and calcination at high temperature. Nickel ions as active component were inlayed in the hexaaluminate lattices to substitute part of Al ions. The structure and properties of these samples were characterized using XRD, XPS, TPR and TGA techniques. The series of hexaaluminates exhibited significantly catalytic activity and stability at high temperature, for instance at 780°C for 18 h, the conversion of CH4 and CO2 was kept over 91.0 and 93.7%, respectively, meanwhile no Ni sintering, phase transformation and catalyst deactivation due to carbon deposition were found. Besides, the modifier A in the mirror plane layer of the lattices showed different effects on reducibility and catalytic activity of transition metal Ni in the hexaaluminate lattices.