Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C.sub.8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene. The catalyst system comprises (a) a first catalyst bed comprising a first catalyst composition, said first catalyst composition comprising a zeolite having a constraint index of 3 to 12 combined (i) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (ii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table; and (b) a second catalyst bed comprising a second catalyst composition, said second catalyst composition comprising (i) a meso-mordenite zeolite, combined (ii) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (iii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table, wherein said meso-mordenite zeolite is synthesized from TEA or MTEA and having a mesopore surface area of greater than 30 m.sup.2/g and said meso-mordenite zeolite comprises agglomerates composed of primary crystallites, wherein said primary crystallites have an average primary crystal size as measured by TEM of less than 80 nm and an aspect ratio of less than 2.

The present invention relates to a method for the preparation of a synthetic crystalline zeolite material, to said synthetic crystalline zeolite material, and to the uses of said method and said synthetic crystalline zeolite material in various applications.

The present invention relates to a method for the preparation of a synthetic crystalline zeolite material, to said synthetic crystalline zeolite material, and to the uses of said method and said synthetic crystalline zeolite material in various applications.

The present invention provides a mordenite zeolite having a mesopore surface area of greater than 30 m.sup.2/g and an average primary crystal size as measured by TEM of less than 80 nm, and methods of making the mordenite zeolite.

The present invention provides a mordenite zeolite having a mesopore surface area of greater than 30 m.sup.2/g and an average primary crystal size as measured by TEM of less than 80 nm, and methods of making the mordenite zeolite.

Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C.sub.8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene. The catalyst system comprises (a) a first catalyst bed comprising a first catalyst composition, said first catalyst composition comprising a zeolite having a constraint index of 3 to 12 combined (i) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (ii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table; and (b) a second catalyst bed comprising a second catalyst composition, said second catalyst composition comprising (i) a meso-mordenite zeolite, combined (ii) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (iii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table, wherein said meso-mordenite zeolite is synthesized from TEA or MTEA and having a mesopore surface area of greater than 30 m.sup.2/g and said meso-mordenite zeolite comprises agglomerates composed of primary crystallites, wherein said primary crystallites have an average primary crystal size as measured by TEM of less than 80 nm and an aspect ratio of less than 2.

Various zeolites may be produced under hydrothermal synthesis conditions in the presence of a silicon atom source and a bis-pyridinium compound having a structure represented by formula (I). Q is an optionally substituted C1-C10 hydrocarbyl group and two Q may join to form a carbocyclic ring; n is an integer ranging from 0 to 5; m is an integer ranging from 0 to 5; n+m is greater than or equal to 1; and A is a spacer group containing 2 to about 10 atoms.

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Compositions and methods for preparing mesoporous and/or mesostructured materials from low SAR zeolites are provided herewith. In particular, methods are provided that involve: (a) providing a low SAR zeolite, (b) optionally subjecting the low SAR zeolite to an acid framework modification, and (c) subjecting the framework-modified zeolite to a mesopore formation treatment. The resulting mesoporous zeolites can have bi-modal mesoporosity and higher aluminum contents relative to existing mesoporous zeolites.

Compositions and methods for preparing mesoporous and/or mesostructured materials from low SAR zeolites are provided herewith. In particular, methods are provided that involve: (a) providing a low SAR zeolite, (b) optionally subjecting the low SAR zeolite to an acid framework modification, and (c) subjecting the framework-modified zeolite to a mesopore formation treatment. The resulting mesoporous zeolites can have bi-modal mesoporosity and higher aluminum contents relative to existing mesoporous zeolites.

Crystalline molecular sieves and their synthesis using quaternary N-methyl-diisoalkylammonium cations as organic structure directing agents are disclosed. The structure directing agent has the following structure (1):

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in which R.sup.1 is selected from hydrogen, a methyl group, an ethyl group, a propyl group, and a hydroxymethyl group; and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are independently selected from a methyl group, an ethyl group, and a propyl group.