title: Solid-state NMR study of ultrastable zeolite Y modified with orthophosphoric acid.
abstract: 29Si, 27Al and 31P solid-state NMR under magic-angle spinning was used for the study of ultrastable zeolite Y modified with H3PO4. The material is a potential candidate for a new generation of oil-cracking catalysts. Bloch decay and cross-polarization spectra were compared. It was found that amorphous aluminium phosphate is formed during the P-impregnation and the following activation, and that it occupies the zeolite surface and internal voids. For a high P-content under steaming conditions, aluminium phosphate is converted into a crystalline form. No evidence has been found for incorporation of P atoms into the zeolite framework.
authors: Universidad Politécnica de Valencia UPV-CSIC, Instituto de Tecnología Química, Spain.
authors: W
authors: W
authors: Kolodziejski
authors: V
authors: V
authors: Fornés
authors: A
authors: A
authors: Corma
mesh_terms: D000535:Aluminum / Q000737:chemistry; D007554:Isotopes; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D010756:Phosphoric Acids / Q000737:chemistry*; D010759:Phosphorus Isotopes; D012825:Silicon / Q000737:chemistry; D017641:Zeolites / Q000032:analysis* / Q000737:chemistry
chemical_list: D007554:Isotopes; D010756:Phosphoric Acids; D010759:Phosphorus Isotopes; D017641:Zeolites; D000535:Aluminum; C030242:phosphoric acid; D012825:Silicon