Characterization of the acid–base properties of transition aluminas by model reaction Original Research Article

The transformation of cyclopentanol and cyclohexanone mixture at 250 °C makes it possible in simple reaction to consider the acidic and basic properties of catalysts. Two reactions take place: the hydrogen transfer on basic sites and the alcohol dehydration on acid sites. These reactions were used to compare the different crystallographic phases of alumina: eta to alpha. From these reactions, we show that aluminas can be divided into two groups: (1) theta and alpha, which possess a basic character close to the one observed on MgO, and (2) eta, gamma and delta, which appear less basic, and possess an acidic character.