Purification of Aromatics over a Promising SO42-/ZrO2 Catalyst

A promising sulfated zirconia(SZ) was successfully synthesized to remove olefins from aromatics. The effects of type and quantity of precipitant, the concentration of impregnants and the calcination temperature were studied, and the synthesized samples were characterized by XRD, SEM, TG-DTG, FTIR, Nadsorption analysis and the FTIR pyridine adsorption(py-IR) techniques. This catalyst was found to be superiorly active as compared with the commercial ROC, which exhibited promising application prospects in industry. The optimum synthesis variables required that SZ was impregnated with 2.0 mol/L sulfuric acid and calcined at 650 ℃, and the precursor was precipitated by ammonium hydroxide to reach eventually a p H value of over 9.46. The addition of SOspecies increased the amount of catalytically active t-ZrO, which was helpful to an increasing abundance of acid sites for enhancing the activity. Meanwhile, the calcination temperature had a great effect on the structure, composition and properties of sulfated zirconia.