Acetylation of Glycerol over Mixed Zirconium Phosphate- Sulphate Catalysts

摘要

In the present work, the acetylation of glycerol over zirconium phosphates and mixed zirconium phosphate sulphate catalysts was investigated. In details, the catalysts with formula Zr3(PO4)4, Zr(SO4)2, Zr2(PO4)2SO4, Zr3(PO4)2(SO4)3and Zr4(PO4)2(SO4)5have been prepared. Characterizations by XRD, FT-IR and acid capacity measurements by titration with NaOH aq. were performed. The glycerol acetylation reactions were performed by using a mass ratio of catalyst/glycerol equal to 5wt% and molar ratio acetic acid/glycerol corresponding to 3:1. The products were analyzed by GC-MS. Zr3(PO4)2(SO4)3, Zr4(PO4)2(SO4)5were the best performing catalysts giving full glycerol conversion in 1h only. Then the activity decreased as a function of the phosphate/sulphate groups. A relationship between acid capacity, activity in glycerol acetylation and selectivity to triacetylglycerol was found. Zr4(PO展开▼