Role of chromium in the stability of Ni/Al2O3 catalysts for natural gas reforming

Ni/Al2O3 and Ni–Cr/Al2O3 catalysts prepared with melt salts of Ni and Al (Al/Ni=0.5) were studied by magnetic measurements, electron microscopy and catalytic properties. An increase in the catalytic activity and stability during partial oxidation of methane and CO2 reforming reactions at 973 K was produced by the chromium addition. The Ni–Cr alloy was formed by reduction at high temperature (1073 K), producing a dilution effect of Ni crystal and modifying the basicity of the support. Both effects would inhibit the catalyst deactivation increasing the useful life and stability of the nickel.