Catalytic properties of Ni-Zn alloy prepared by mechanical alloying for steam reforming from methanol

Abstract

Amorphous Zn₆₅Ni₃₅ alloy, the composition of which lies between β₁-NiZn and γ-NiZn phases, was prepared by mechanical alloying for 200 hours. The alloy was heat treated at various temperatures and leached in NaOH solution in an effort to enhance the catalytic properties for hydrogen production from methanol. X-ray diffraction study revealed that the amorphous phase crystallized during the heat treatment to the equilibrium β₁-NiZn and γ-NiZn phases. It was found that Zn₆₅Ni₃₅ alloy leached after heat treatment at 928 K showed the highest catalytic activity for steam reforming of methanol. It is believed that the enhanced catalytic activity of the Zn₆₅Ni₃₅ alloy heat treated at 928 K is due to the dispersed Ni particles on β₁-ZnNi matrix which was formed during leaching of the γ-Zn₂₁Ni₅ phase.