Effect of Acid‐Base Properties of Oxide Catalysts on Glycerol Transformation into Diglycerides

Abstract Glycerol oligomerization in a liquid phase was studied over the acid‐base bifunctional catalysts for the following oxides: TiO 2 , ZrO 2 , CeO 2 , binary CeO 2 −ZrO 2 systems, and purely basic oxide MgO. The phase composition and surface area have been estimated by XRD and BET. The acid and basic properties of catalysts have been characterized using the quasi‐equilibrium thermal desorption (QE‐TD) of NH 3 (acidity) and CO 2 (basicity). Attenuated total reflectance FTIR (ATR‐FTIR) spectroscopy provided qualitative insights into the interactions in the oxide‐glycerol systems. A comparison of catalytic and acid‐base properties of the oxide systems showed that the reaction requires the presence of both acid and base sites in the catalyst. Moreover, the strength of base sites should exceed the strength of acid sites.