Aluminium and gallium dawsonites were prepared by the in-line dispersion-precipitation method and thermally treated in the range 373 873 K to produce aluminium and gallium oxides. These materials were fully characterised and studied as catalysts for the epoxidation of cyclooctene with hydrogen peroxide. The temperature at which the dawsonite precursors were treated proved to be crucial in determining the activity of the catalysts. Remarkably, the catalysts derived from Al-dawsonite calcined between 473 and 673 K displayed an enhanced epoxidation activity upon recycling. The best catalyst identified in this work is a gallium oxide obtained by the calcination at 573 K of Ga dawsonite prepared by a reconstruction procedure. This material provides an epoxide yield of 51% with a selectivity of 99% after 4 h of reaction at 353 K.