Pd/transition metal oxides functionalized ZSM-5 single crystals with b-axis aligned mesopores: Efficient and long-lived catalysts for benzene combustion

• Published in: Applied catalysis. B, Environmental Vol. 148-149; pp. 106 - 113
• Main Authors: Liu, Fujian, Zuo, Shufeng, Wang, Chao, Li, Jiantao, Xiao, Feng-Shou, Qi, Chenze
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 27-04-2014; Elsevier
• Subjects: Alignment; Amphiphilic copolymer; b-axis aligned mesopores; Catalysis; Catalysts; Chemistry; Colloidal state and disperse state; Combustion; Exact sciences and technology; General and physical chemistry; Ion-exchange; Mesoporous zeolites; Porous materials; Self assembly; Single crystals; Surface physical chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Transition metal oxides; VOCs removing; Zeolites; Zeolites: preparations and properties; b-axis aligned mesopores; Self-assembly; VOCs removing; Amphiphilic copolymer; Mesoporous zeolites; Self assembly; Oxides; Combustion; Transition metal; Porous material; Single crystal; Mesoporosity; Heterogeneous catalysis; Benzene; Copolymer; Catalyst; Environmental protection
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2013.10.054

Efficient and long lived catalysts for VOCs combustion have been successfully synthesized from loading of PdO&La2O3 nanocrystals in ZSM-5 single crystals with b-axis aligned mesopores.▪•SM-5 single crystals (ZSM-5-OM) with b-axis-aligned mesopores were prepared.•Pd/Transition metal oxides nanocrystals were loaded into ZSM-5-OM.•The active species in ZSM-5-OM show good dispersion and unique interactions.•The interactions of various active species result in their low reductive temperature.•SM-5-OM based catalysts show good catalytic performance for benzene combustion.
A series of PdO/transition metal oxides functionalized mesoporous ZSM-5 single crystals with b-axis aligned mesopores (x%Pd/x%M-ZSM-5-OMs) have been successfully prepared from self-assembly of the designed cationic amphiphilic copolymer of polystyrene-co-poly4-vinylpyridine (C-PSt-co-P4VP) with ZSM-5 zeolite precursor based on their strong positive-negative charge interaction under high temperature hydrothermal conditions. Characterizations of XRD patterns showed that x%Pd/x%M-ZSM-5-OMs exhibit good crystallinity with typical MFI zeolite characters; N2 isotherms showed that x%Pd/x%M-ZSM-5-OMs have large BET surface areas and mesopore volumes. SEM images showed the single crystal structure of x%Pd/x%M-ZSM-5-OMs, which have abundant and b-axis aligned mesopores, running through the whole zeolite crystals. TEM images further confirmed b-axis aligned mesopores, and good dispersion of active sites with high degree of crystallinity in x%Pd/x%M-ZSM-5-OMs. XPS spectra showed that transition metal oxides and PdO active species have been successfully loaded into ZSM-5-OM support. H2–TPR curves showed the low reduction temperatures of PdO and transition metal species in x%Pd/x%M-ZSM-5-OMs, which was favorable for the enhancement of their abilities for VOCs combustion. Catalytic tests showed that x%Pd/x%M-ZSM-5-OMs exhibit good catalytic activities and long catalytic lives for benzene combustion under rather mild conditions in comparison with that of x%Pd/x%M-ZSM-5, which would be very important for the wide applications of zeolites with controlled mesopores in the areas of VOCs oxidation.