Hexane Isomerization over Hierarchical Pt/MFI Zeolite

Chao, Pei-Hsiun; Tsai, Shang-Tien; Chang, Shu-Lang; Wang, Ikai; Tsai, Tseng-Chang

doi:10.1007/s11244-009-9416-9

Cited by 16 publications

(4 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In recent years, hierarchical zeolites have been investigated on this reaction. For example, hierarchical MFI zeolite prepared through post-desilication and subsequent re-crystallization route was tested in this reaction at 327°C [102]. The results showed that the hierarchical MFI zeolite produced branched isomers such as 2,2-dimethylbutane having higher octane-value than the parent n-hexane.…”

Section: Hydrocarbon Isomerizationmentioning

confidence: 99%

Hierarchically Nanoporous Zeolites and Their Heterogeneous Catalysis: Current Status and Future Perspectives

Somorjai

2014

Catal Lett

View full text Add to dashboard Cite

The research field of hierarchically nanoporous zeolites has been growing at an enormous pace over the past decades. Hierarchically nanoporous zeolites have versatile structural properties such as high surface area and large pore volume that can alleviate diffusional limitations of conventional zeolites with solely microporous framework. In this review, various synthesis strategies to hierarchically nanoporous zeolites and their structural advantages in catalytic reactions will be reviewed. In the first part, many novel synthetic approaches for hierarchically nanoporous zeolites such as post-demetallation, softtemplating, hard-templating, and dual-pore-generating surfactant-directed methods will be introduced. In the second part, catalytic applications of hierarchically nanoporous zeolites on various chemical reactions involving isomerization, cracking, alkylation and oxidation will be discussed. The present comprehensive review will provide future opportunities and perspectives on the research of hierarchically nanoporous zeolites including their applications to catalytic reactions.

show abstract

Section: Hydrocarbon Isomerizationmentioning

confidence: 99%

Hierarchically Nanoporous Zeolites and Their Heterogeneous Catalysis: Current Status and Future Perspectives

Somorjai

2014

Catal Lett

View full text Add to dashboard Cite

show abstract

“…To prevent the metal aggregation, the introduction of a mesoporous system into the microporous zeolite network can greatly improve the dispersion of metal species due to a large increasing number of defect sites [33]. With the benefits of mesoporous or hierarchical structures [34,35], an improved catalytic efficiency has been observed in some reactions, in particular the processes involving bulky molecules, such as hydroisomerization, aromatization and hydrodesulfurization, as compared to a conventional zeolite [36][37][38][39][40].…”

Section: Introductionmentioning

confidence: 99%

Dehydrogenation of Propane to Propylene Using Promoter-Free Hierarchical Pt/Silicalite-1 Nanosheets

et al. 2019

View full text Add to dashboard Cite

Propane dehydrogenation (PDH) is the extensive pathway to produce propylene, which is as a very important chemical building block for the chemical industry. Various catalysts have been developed to increase the propylene yield over recent decades; however, an active site of monometallic Pt nanoparticles prevents them from achieving this, due to the interferences of side-reactions. In this context, we describe the use of promoter-free hierarchical Pt/silicalite-1 nanosheets in the PDH application. The Pt dispersion on weakly acidic supports can be improved due to an increase in the metal-support interaction of ultra-small metal nanoparticles and silanol defect sites of hierarchical structures. This behavior leads to highly selective propylene production, with more than 95% of propylene selectivity, due to the complete suppression of the side catalytic cracking. Moreover, the oligomerization as a side reaction is prevented in the presence of hierarchical structures due to the shortening of the diffusion path length.

show abstract

“…However, the use of desilicated zeolites as bifunctional catalysts, particularly in short chain n-alkane transformation, has been scarcely explored. For instance, Chao et al [20] explored the potentialities of mesoporous ZSM-5 obtained by alkaline post-treatments and observed changes in the product selectivity and adsorption properties. Song et al [21] studied the effect of the desilication treatment on ZSM-5, and observed an enhancement in the yield of dibranched isomers due to the formation of mesopores.…”

Section: Introductionmentioning

confidence: 99%

Catalytic behavior of alkali-treated Pt/HMOR in n-hexane hydroisomerization

Monteiro

Ania

Rocha

et al. 2014

Applied Catalysis A: General

View full text Add to dashboard Cite

Bifunctional Pt-HMOR catalysts were prepared by incipient wetness impregnation of various desilicated MOR obtained by alkaline treatment using NaOH concentrations ranging from 0.1 to 0.5 M. The zeolite structural changes upon modification were investigated by several techniques including powder X-ray diffraction, 27 Al and 29 Si MAS-NMR spectroscopy, N 2 adsorption, pyridine adsorption followed by infrared spectroscopy and the catalytic model reaction of m-2 xylene transformation. For low alkaline concentration the zeolite acidity is preserved, along with a slight increase of the volume correspondent to the larger micropores due to the removal of extra-framework debris already existent at the parent zeolite At higher NaOH concentrations there is a significant loss of crystalinity and acidity as well as the formation of mesoporosity. The characterization of the metal function show similar patterns for Pt-HMOR and Pt-M/0.1 samples, with Pt particles located mainly inside the inner porosity. In contrast, large Pt particles become visible at the intercrystalline mesoporosity of MOR crystals developed during the desilication treatments at severe alkaline conditions. The catalytic results obtained for n-hexane hydroisomerization showed an improved selectivity for dibranched over monobranched isomers for Pt-M/0.1 sample, likely due to the preservation of the support acidity and the slight enlargement of the micropores. This work is a new example in which the mesoporous development does not improve the catalytic efficiency of the zeolites, whereas mild alkaline desilication might be considered as an effective solution to produce customized catalysts with enhanced performance for a given application.

show abstract

Hexane Isomerization over Hierarchical Pt/MFI Zeolite

Cited by 16 publications

References 27 publications

Hierarchically Nanoporous Zeolites and Their Heterogeneous Catalysis: Current Status and Future Perspectives

Hierarchically Nanoporous Zeolites and Their Heterogeneous Catalysis: Current Status and Future Perspectives

Dehydrogenation of Propane to Propylene Using Promoter-Free Hierarchical Pt/Silicalite-1 Nanosheets

Catalytic behavior of alkali-treated Pt/HMOR in n-hexane hydroisomerization

Contact Info

Product

Resources

About