NiSO4Supported on FeO-promoted ZrO2Catalyst for Ethylene Dimerization

Abstract

The NiSO 4 supported on FeO-promoted ZrO 2 catalysts were prepared by the impregnation method. FeO-promoted ZrO 2 was prepared by the coprecipitation method using a mixed aqueous solution of zirconium oxychloride and ironnitrate solution followed by adding an aqueous ammonia solution. The addition of nickel sulfate (or FeO) to ZrO 2 shifted the phase transition of ZrO 2 (from amorphous to tetragonal) to higher temperatures because of the interaction between nickel sulfate (or FeO) and ZrO 2 . 10-NiSO 4 /5-FeO-ZrO 2 containing 10 wt % NiSO 4 and 5 mol % FeO, and calcined at 500 °C exhibited a maximum catalytic activity for ethylene dimerization. NiSO 4 /FeO-ZrO 4 catalysts was very effective for ethylene dimerization even at room temperature, but Fell-ZrO 2 without NiSO 4 did not exhibit any catalytic activity at all. The catalytic activities were correlated with the acidity of catalysts measured by the ammonia chemisorption method. The addition of FeO up to 5 mol.% enhanced the acidity, surface area, thermal property, and catalytic activities of catalysts gradually, due to the interaction between FeO and ZrO 2 and due to consequent formation of Fe-O-Zr bond.