Glycerol acetylation on sulphated zirconia in mild conditions

This work focuses on the role of the hydrolysis ratio over the physicochemical properties of sulphated zirconia (SZ) obtained by the sol-gel method. The solids obtained were tested in the esterification of acetic acid diluted in glycerol, the latter being used both as reactant and solvent. The acidic properties of the SZ samples and their performances in the acetylation reaction have been successfully correlated. The recyclability has also been studied: sample SZ-1 (sulphated zirconia prepared with a hydrolysis molar ratio = 1) shows a progressive deactivation in successive tests due to sulphur leaching which induces an activity in the homogeneous phase.