Influence of the lithium content on the state, dispersion and reducibility of nickel oxide supported on γ-alumina

Abstract

The influence of lithium on the dispersion, active phase-carrier interaction and reducibility of nickel oxide supported on alumina carriers has been investigated using X-ray diffraction analysis (X.r.d.), ultraviolet diffuse reflectance spectroscopy (d.r.s.), X-ray photoelectron spectroscopy (X.p.s.) and temperature programmed reduction (t.p.r.).

On Li-free alumina, nickel is present in the form of a NiAl₂O₄ compound and dispersed NiO. Increasing the Li content leads to a decrease in the formation of NiAl₂O₄, due, presumably, to the concurrent formation of Li-containing spinel phases, and a concurrent increase in the reducibility of the nickel-containing phase.