State of the art and future challenges of zeolites as catalysts

Mesopore-modified zeolites: preparation, characterization, and applications.

Amongst the current developments in the field of hierarchical pore structures, the creation of mesopores in zeolite crystals is the most frequently employed way to combine micropores with mesopores in one material. In this review an overview is presented of the different approaches to generate and characterize mesopores in zeolite crystals and establish their impact on the catalytic action. Mesopores can be created via several routes from which steaming and acid leaching are the most frequently applied. Novel approaches using secondary carbon templates that are removed after synthesis have recently been launched. For the characterization of mesopores, nitrogen physisorption and electron microscopy are commonly used. More recently, it was shown that electron tomography, a form of three-dimensional transmission electron microscopy, is able to reveal the three-dimensional shape, size, and connectivity of the mesopores. The effect of the presence of mesopores for catalysis is demonstrated for several industri...

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Generation, Characterization, and Impact of Mesopores in Zeolite Catalysts

Acid catalysts in industrial hydrocarbon chemistry.

The discovery of ordered mesoporous materials has opened great opportunities for new applications in heterogeneous catalysis, thanks to their hitherto unprecedented intrinsic structural features. Evidence shows that, however, these materials have not met the researchers' expectations mainly because of the severe limitations related to the strength of acid sites and to the thermal/hydrothermal stability, significantly lower than those of zeolites and due to the amorphous nature of the mesostructured materials. These features are highlighted in the first part of this review, where the peculiarities of mesostructured materials are compared with those of zeolite catalysts in some reactions of industrial interest. New synthesis strategies, especially designed for preparing materials with improved physico-chemical and textural properties, together with the catalytic features of the resulting materials, are described and discussed in the second part of the review.

Porous materials in catalysis: challenges for mesoporous materials

Liquid-Phase Alkylation of Benzene with Light Olefins Catalyzed by β-Zeolites

Experimental and Computational Study of Beta, ZSM-12, Y, Mordenite and ERB-1 in Cumene Synthesis

Publisher Summary This chapter presents the methylation of naphthalene and methylnaphthalene with zeolitic catalysts. The main purpose is to achieve a selective synthesis of 2,6-dimethylnaphthalene (2,6-dmn). Best performances are obtained with 1,2,4-trimethylbenzene as solvent or reagent, together with methanol. In such chemical system, among several medium and large pore zeolites, MTW stands out for both activity and selectivity to 2,6-dmn. As transalkylation is the main reaction, this behavior can be explained if a restricted transition-state shape selectivity takes place.

G. Terzoni

Papers

Liquid-Phase Alkylation of Benzene with Light Olefins Catalyzed by β-Zeolites

Experimental and Computational Study of Beta, ZSM-12, Y, Mordenite and ERB-1 in Cumene Synthesis

25-O-03 - Selective alkylation of naphthalene to 2,6-dimethylnaphthalene catalyzed by MTW zeolite

Liquid‐Phase Alkylation of Benzene with Light Olefins Catalyzed by . beta. Zeolites.