A comparison of sol–gel and impregnated Pt or/and Ni based γ-alumina catalysts for bioglycerol aqueous phase reforming

Two series of Pt or/and Ni-based γ-alumina catalysts were prepared using sol–gel and conventional impregnation methods. Their activities were tested in the aqueous phase reforming of glycerol. All catalysts were also characterized by different techniques such as: ICP, BET, TPR-H2, in situ XPS and XRD to study their textural and physicochemical properties. The effect of preparation method, nature of active phase and possible cooperative effect between Pt and Ni in catalytic performance have been the focus of this investigation. The results obtained showed that sol–gel catalysts present better catalytic properties. TPR-H2, XPS and XRD showed that sol–gel PtNiAl catalyst contain well dispersed active phases and present high resistance against sintering leading to better and more stable catalytic activities, especially at moderate temperature/pressure conditions. As a result, sol–gel PtNi catalysts allowed higher reforming rates (3–8 times) to gaseous products than PtNi catalysts prepared by incipient wetness impregnation. This better behavior can be explained by the enhancement of textural properties, higher active phases dispersion and cooperative effect between Pt and Ni elements.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Pt/Ni based γ-Al2O3 catalysts for H2 production by APR of bioglycerol was studied. ► SGB method allows to PtNiAl catalyst with high surface area/porosity and good dispersion. ► Cooperative effect between Pt and Ni provide a better performance of PtNiAl catalysts. ► The APR behavior of the catalysts is more stable at moderate temperature/pressure reactions. ► Pt promotes H2-rich gas, while Ni is more selective to alkanes, but PtNi led to an intermediate behavior.