The invention relates to a process for preparing an AFX-structure zeolite comprising at least the following steps: i) mixing, in an aqueous medium, an FAU-structure zeolite having an SiO.sub.2 (FAU)/Al.sub.2O.sub.3 (FAU) molar ratio of between 2.00 (limit included) and 6.00 (limit excluded), an organic nitrogenous compound R, at least one source of at least one alkali and/or alkaline-earth metal M, the reaction mixture having the following molar composition: (SiO.sub.2 (FAU))/(Al.sub.2O.sub.3 (FAU)) between 2.00 (limit included) and 6.00 (limit excluded), H.sub.2O/(SiO.sub.2 (FAU)) between 1 and 100, R/(SiO.sub.2 (FAU)) between 0.01 and 0.6, M.sub.2/nO/(SiO.sub.2 (FAU)) between 0.005 and 0.7, limits included, until a homogeneous precursor gel is obtained; ii) hydrothermal treatment of said precursor gel obtained on conclusion of step i) at a temperature of between 120° C. and 220° C., for a time of between 12 hours and 15 days.

The invention relates to a process for preparing an AFX-structure zeolite comprising at least the following steps: i) mixing, in an aqueous medium, an FAU-structure zeolite having an SiO.sub.2 (FAU)/Al.sub.2O.sub.3 (FAU) molar ratio of between 2.00 (limit included) and 6.00 (limit excluded), an organic nitrogenous compound R, at least one source of at least one alkali and/or alkaline-earth metal M, the reaction mixture having the following molar composition: (SiO.sub.2 (FAU))/(Al.sub.2O.sub.3 (FAU)) between 2.00 (limit included) and 6.00 (limit excluded), H.sub.2O/(SiO.sub.2 (FAU)) between 1 and 100, R/(SiO.sub.2 (FAU)) between 0.01 and 0.6, M.sub.2/nO/(SiO.sub.2 (FAU)) between 0.005 and 0.7, limits included, until a homogeneous precursor gel is obtained; ii) hydrothermal treatment of said precursor gel obtained on conclusion of step i) at a temperature of between 120° C. and 220° C., for a time of between 12 hours and 15 days.

This disclosure provides improved processes for converting benzene/toluene via methylation with methanol/dimethyl ether for producing, e.g., p-xylene. In an embodiment, a process comprises contacting a methylation agent feed with an aromatic hydrocarbon feed in the presence of a methylation catalyst in a methylation reactor at increased pressure. Reduced methylation catalyst deactivation can be achieved with increased pressure in the methylation reactor.

Provided is a beta-type zeolite which has a high catalytic activity and is not easily deactivated.

The beta-type zeolite of the invention has a substantially octahedral shape, has a Si/Al ratio of 5 or more, and is a proton-type zeolite. The Si/Al ratio is preferably 40 or more. This beta-type zeolite is preferably obtained by transforming a raw material beta-type zeolite synthesized without using a structure directing agent into an ammonium-type zeolite through ion exchange, then, exposing the beta-type zeolite to water vapor, and subjecting the exposed beta-type zeolite to an acid treatment.

Provided is a beta-type zeolite which has a high catalytic activity and is not easily deactivated.

The beta-type zeolite of the invention has a substantially octahedral shape, has a Si/Al ratio of 5 or more, and is a proton-type zeolite. The Si/Al ratio is preferably 40 or more. This beta-type zeolite is preferably obtained by transforming a raw material beta-type zeolite synthesized without using a structure directing agent into an ammonium-type zeolite through ion exchange, then, exposing the beta-type zeolite to water vapor, and subjecting the exposed beta-type zeolite to an acid treatment.

A ceramic honeycomb structure comprising large numbers of cells partitioned by porous cell walls, the cell walls having (a) porosity of 50-80%, and when measured by mercury porosimetry, (b) a median pore diameter being 25-50 μm, (c) (i) a cumulative pore volume in a pore diameter range of 20 μm or less being 25% or less of the total pore volume, (ii) a cumulative pore volume in a pore diameter range of more than 20 μm and 50 μm or less being 50% or more of the total pore volume, and (iii) a cumulative pore volume in a pore diameter range of more than 50 μm being 12% or more of the total pore volume.

A ceramic honeycomb structure comprising large numbers of cells partitioned by porous cell walls, the cell walls having (a) porosity of 50-80%, and when measured by mercury porosimetry, (b) a median pore diameter being 25-50 μm, (c) (i) a cumulative pore volume in a pore diameter range of 20 μm or less being 25% or less of the total pore volume, (ii) a cumulative pore volume in a pore diameter range of more than 20 μm and 50 μm or less being 50% or more of the total pore volume, and (iii) a cumulative pore volume in a pore diameter range of more than 50 μm being 12% or more of the total pore volume.

To provide a functional structural body that can realize a long life time by suppressing the decline in function of the functional substance and that can attempt to save resources without requiring a complicated replacement operation, and to provide a method for making the functional structural body. The functional structural body (1) includes a skeletal body (10) of a porous structure composed of a zeolite-type compound, and at least one functional substance (20) present in the skeletal body (10), the skeletal body (10) has channels (11) connecting with each other, and the functional substance is present at least in the channels (11) of the skeletal body (10).

To provide a functional structural body that can realize a long life time by suppressing the decline in function of the functional substance and that can attempt to save resources without requiring a complicated replacement operation, and to provide a method for making the functional structural body. The functional structural body (1) includes a skeletal body (10) of a porous structure composed of a zeolite-type compound, and at least one functional substance (20) present in the skeletal body (10), the skeletal body (10) has channels (11) connecting with each other, and the functional substance is present at least in the channels (11) of the skeletal body (10).

The present invention relates to a new chiral zeolite material of composition a SiO.sub.2:b GeO.sub.2:c X.sub.2O.sub.3:d YO.sub.2, with an ITV structure, prepared with a specific chiral organic structure-directing agent, (1S,2S)—N-ethyl-N-methyl-pseudoephedrine or its enantiomer, (1R,2R)—N-ethyl-N-methyl-pseudoephedrine, which means that the material is rich in one of the crystalline forms; a method whereby said material is obtained, and the use thereof in adsorption and catalysis processes.