Synthesis and catalytic properties of mesoporous alumina supported aluminium chloride with controllable morphology, structure and component

Abstract

Aluminium chloride supported by tubular alumina, which was treated by absorbent cotton as a template, was prepared via chemical tailoring method. Scanning electron microscopy, transmission electron microscopy, N2 adsorption techniques and X-ray diffraction characterization showed alumina well replicated the nanoporous morphologies and hierarchical pore size of original cotton, and via chemical tailoring method, the active component aluminium chloride distributed evenly on the surface of the support. Using different concentration of hydrochloric acid, the morphology, structure and component of tubular alumina supported aluminium chloride could be controllably synthesized. The Baeyer–Villiger oxidation reactions of ketones catalyzed by the supported aluminium chloride, with 30% hydrogen peroxide as an oxidant, were carried out. The experimental results revealed that this type of reactions could proceed in ethanol at 70 °C with good yield (96%) and high regioselectivity (99%), exemplified by transforming of 2-adamantanone. The tubular alumina supported aluminium chloride could be reused several times without significant losses of their catalytic activity and selectivity.