Structural evolution and catalytic performance of DuPont V-P-O/SiO2 materials designed for fluidized bed applications

An industrial V-P-O catalyst (DuPont), comprising vanadyl pyrophosphate crystallites encapsulated by a silica shell, has been investigated. Reaction evaluation for butane oxidation was conducted over (i) the catalyst precursor, (ii) the calcined precursor and (iii) equilibrated material (2 years on-line) in a fixed-bed reactor. Characterization was conducted on these three samples by XRD, SEM, TEM and XPS. The core–shell particles have also been examined with a novel X-ray ultramicroscopy (XuM) technique which reveals the internal structure without having to section the material. The microstructural and surface compositional changes that have occurred over the course of its industrial lifespan in a fluidized bed reactor are correlated with the catalytic activity measurements.

Graphical abstractAn industrial V-P-O catalyst (DuPont), comprising vanadyl pyrophosphate crystallites enclosed by a silica shell, has been investigated for butane oxidation and studied by standard characterization techniques. Additionally, the core–shell particles have been non-destructively examined with a novel X-ray ultramicroscopy (XuM) technique which reveals the internal structure. The microstructural and surface compositional changes occurring during the industrial lifespan of the catalyst in a fluidized bed reactor are described.Figure optionsDownload full-size imageDownload high-quality image (69 K)Download as PowerPoint slide