γ-Al2O3 Modified with Praseodymium: An Application in the Heterogeneous Catalytic Ozonation of Succinic Acid in Aqueous Solution

In an attempt to utilize ozone effectively, a series of praseodymium-modified gamma-Al2O3 (Pr/Al2O3) was prepared via incipient wetness impregnation using Pr(NO3)(3) 6H(2)O as the precursor The structure and properties of the catalysts were studied by X-ray diffraction (XRD) and the Brunauer-Emmett-Teller (BET) method Catalytic activity was evaluated by monitoring the degradation of succinic acid (SA) in the presence of ozone The praseodymium modification can effectively enhance the zonation activity of gamma-Al2O3 upon SA removal Increasing the calcination temperature of Pr/Al2O3 is disadvantageous for the catalytic process, whereas increasing the load of praseodymium is helpful After three successive cycles, the Pr/Al2O3 catalyst remained stable in the catalytic zonation of SA Overall, the initial degradation rate of SA, as well as the saturated adsorption capacity of SA, were found to have a linear relation to changes of the surface hydroxyl groups of the catalyst On this basis, we conclude that the significant enhancement of SA degradation using Pr/Al2O3 as a catalyst should be because praseodymium, in the form of Pr6O11, promoted the formation of surface hydroxyl groups Hence, the adsorption was increased, and the degradation rate of SA was enhanced