Ni-loaded Catalyst Containing Activated Clay for Maleic Anhydride Hydrogenation to Succinic Anhydride

In this work, the hydrogenation of maleic anhydride to succinic anhydride in the presence of 5 m%Ni/clay cata- lysts was investigated. These catalysts were characterized by X-ray diffraction (XRD), H2 temperature programmed reduc- tion (TPR) and thermogravimetric analysis (TGA) techniques. The XRD and TPR studies showed that Ni was present as Ni 2+ on the support, which indicated that there were no elemental nickel (Ni 0 ) and Ni2O3 species in the unreduced samples. Increasing of calcination temperature to 650 ℃ leads to destruction of the support structure observed in TGA, while the cat- alyst sample calcined at 550 ℃ exhibits better performances than other samples. The ideal conversion of maleic anhydride (97.14%) and selectivity of succinic anhydride (99.55%) were realized at a reaction temperature of 180 ℃ and a weight hourly space velocity of 4 h -1 under a reaction pressure of 1 MPa.