On the Mechanism of Propane Dehydrocyclization over Cation-Containing, Proton-Poor MFI Zeolite

Significant Influence of Zn on Activation of the C‐H Bonds of Small Alkanes by Brønsted Acid Sites of Zeolite

“…[1][2][3][4] The role of the metal species and acid sites of a zeolite in the enhancement of light alkane conversion to aromatics remains a subject of intense controversy, even after significant emphasis and numerous publications. [1,2,[5][6][7][8][9][10][11][12][13][14][15][16] On the one hand, there is agreement on the bifunctional nature of these catalysts, where the metal species are responsible for the dehydrogenation of alkanes, while the Brønsted acid sites are involved in the oligo-A C H T U N G T R E N N U N G merization and cyclization of olefins. [3,17] On the other hand, it has been claimed that the activation and cleavage of CÀH bonds of alkanes occurs predominantly at the Brønsted acid sites.…”

Olefin reduction of FCC gasoline via hydroisomerization aromatization over modified HMOR/HZSM-5/Hβ composite carriers

“…However, a single ZSM-5 zeolite gave low selectivity for the conversion of alkanes to aromatics [17,18], because an effective reaction sequence from alkanes to aromatics requires the presence of both acid sites and dehydrogenation centers. Ono et al [19] showed that the introduction of Ga or Zn species had a positive effect on the rate and selectivity of alkane aromatization.…”

Combined experimental and kinetic modelling studies of the pathways of propane and n-butane aromatization over H-ZSM-5 catalyst

“…This selectivity, however, can be increased significantly by using metal-containing ZSM-5 catalysts instead of the H-ZSM-5. Most of the investigators seem to agree (Biscardi and Iglesia, 1999;Guisnet et al, 1992;Guisnet and Gnep, 1996;Meriaudeau and Naccache, 1997;Ono, 1992;Price et al, 1998) that metal species provide additional dehydrogenation routes for the feed alkane transformation into corresponding alkene (contribution to the stage 1, Fig. 1) and for the transformation of the alkenes into aromatics and hydrogen (contribution to the stage 3, Fig.…”