Characterization of a chromia-alumina catalyst using small-angle neutron scattering

Neutron scattering has been employed to study the pore structure of a chromia-alumina catalyst. The results indicated the existence of three distinct scattering regimes with distinct slopes corresponding to the values of the wavevector, Q. The analysis of the scattering in these regions suggested that the large-Q region corresponds to Porod's law scattering and provides information on the specific surface area. The intermediate Q region arises from scattering from hollow capillaries and provides information on the dimension of the capillaries. The small-Q behaviour arises from the relative spatial arrangement of capillaries, which appear to form a `fractal' network.