Pd–palygorskite catalysts: Preparation, characterization and catalytic performance for the oxidation of styrene

• Pd–palygorskite (Pd–PAL) catalyst was prepared by a simple ion-exchange method.
• The Pd–PAL interactions assure good catalytic performance for styrene epoxidation.
• The heterogeneously Pd-catalyzed epoxidation of the CC bonds is uncommon till now.
• The ion-exchanged Pd NPs can be recycled without loss of catalytic efficiency.

Palygorskite (PAL) supported Pd nanoparticle (NP) catalyst was prepared by a simple ion-exchange method. This catalyst showed good catalytic performance for the oxidation of styrene epoxidation (95.2% conversion and 90.2% epoxidation selectivity, TON as high as 13,448 could be achieved). This catalyst was characterized by TEM, XRD, FT-IR and XPS, the data reveal the presence of strong interaction between Pd NP and PAL supports, and the good catalytic performance is closely related to this interaction and the surface polarity of PAL. Meanwhile, the ion-exchanged Pd NPs can be recycled without loss of catalytic efficiency. Ultimately, some reaction parameters have been investigated and reaction conditions are optimized.

Pd–palygorskite (Pd–PAL) catalyst was prepared by a simple ion-exchange method and shown. The exchanged Pd nanoparticles (NPs) are surrounded by basal oxygen atoms. Most of them existed in the virtual homogeneous coordination environment. The interactions between Pd NPs and PAL assure the high dispersion of Pd NPs, together with the surface polarity of PAL, and are responsible for the good catalytic performance. Meanwhile, the ion-exchanged Pd NPs can be recycled without loss of catalytic efficiency. This catalytic system will promote the application of PAL material in catalysis.TEM image of Pd/PAL catalyst and reaction mechanism.Figure optionsDownload as PowerPoint slide