Reforming of methane with carbon dioxide over calcium-modified Ni/La2O3 catalysts

Precursors prepd. by solid phase crystn., La2-zCazNiO4 (z = 0, 0.25, 0.5, and 0.75), and reduced with (5:95) Hi(2)-Ar gave Ni/La2O3 and Ni/CaO-La2O3 as phase components (XRD). At 700 degrees C, the redn. La2NiO4 -> La2O3 + Ni-o gave 15-nm active Ni crystallites regardless of the z. At z < < 0.25, Ca suppressed coking and, at z >= 0.5, suppressed the formation of H2O. At z = 0.25 and 0.75, the C activation energies were 136 and 306 kJ/mol, resp. The Ca/Ni = 1:2 ratio was optimum for either effect At z >= 0.5, CaO was a phase component (XRD). Activation energies were evaluated at 600 degrees C for each product.