title: Synthesis of Pt modified ZSM-5 and beta zeolite catalysts: influence of ultrasonic irradiation and preparation methods on physico-chemical and catalytic properties in pentane isomerization.
abstract: Influence of preparation methods and ultrasound irradiation on physico-chemical and catalytic properties was investigated by synthesizing Pt-ZSM-5 and Pt-Beta catalysts by in-situ and impregnation methods and applying ultrasound irradiation to synthesis gel mixture of ZSM-5 and Beta zeolites. It was concluded from the X-ray powder diffraction patterns of Pt-ZSM-5 and Pt-Beta zeolite catalysts that introduction of Pt by in-situ method and ultrasound irradiation did not influence the structures of ZSM-5 and Beta zeolites. Morphology of ZSM-5 and Beta zeolites were investigated by scanning electron microscopy. SEM micrographs showed that the Pt-ZSM-5-IS-US catalyst synthesized by in-situ method with ultrasound irradiation resulted in smaller crystals of ZSM-5 than Pt-ZSM-5-IS catalyst prepared without ultrasound irradiation. Furthermore SEM micrographs of Pt-Beta-11-IS-US zeolite synthesized using ultrasound irradiation showed much smaller crystals than Pt-Beta-11-IM indicating that ultrasound irradiation had a significant effect on the morphology of Beta zeolite. Conversion of n-pentane and selectivity to iso-pentane over the Pt-ZSM-5-IS-US zeolite catalysts prepared by ultrasound irradiation during in-situ introduction of platinum was higher than the catalysts prepared without the ultrasound irradiation. Furthermore ultrasound irradiated and in-situ synthesized Pt-Beta-11-IS-US catalyst also showed higher selectivity to iso-pentane than Pt-H-Beta-11-IM prepared by impregnation method.
authors.affiliation: Laboratory of Industrial Chemistry, Process Chemistry Centre, Abo Akademi University, FIN-20500 Turku/Abo, Finland.
authors.forename: N
authors.initials: N
authors.lastname: Kumar
authors.forename: O V
authors.initials: OV
authors.lastname: Masloboischikova
authors.forename: L M
authors.initials: LM
authors.lastname: Kustov
authors.forename: T
authors.initials: T
authors.lastname: Heikkilä
authors.forename: T
authors.initials: T
authors.lastname: Salmi
authors.forename: D Yu
authors.initials: DY
authors.lastname: Murzin