Influence of morphology of zirconium-doped mesoporous silicas on 5-hydroxymethylfurfural production from mono-, di- and polysaccharides

Different zirconium-doped mesoporous silicas (Zr-KIT-6, Zr-SBA-15, Zr-MCM-41 and Zr-HMS) were synthesized evaluated in the glucose dehydration to 5-hydroxymethylfurfural (HMF). A Si/Zr molar ratio of 5 was chosen for this purpose after optimization parameter KIT-6 support. These materials characterized by using XRD, N2 sorption, TEM, XPS, NH3-TPD pyridine adsorption coupled FTIR spectroscopy. All catalysts active dehydration, being HMF main product, their catalytic performance enhanced CaCl2 addition reaction medium. However, Zr-doped HMS silica showed highest values conversion yield, mainly at short times, due catalyst displayed surface zirconium concentration its 3D morphology favored access molecules sites. This fact also caused a faster deactivation coke deposition on surface, although leaching negligible. The Zr-HMS(5) could be reused four runs without any treatment initial activity recovered washing with water acetone. demonstrated hydrolysis disaccharides polysaccharides, such as sucrose, maltose, cellobiose, inulin cellulose, subsequent resulting monomers production.