Disclosed are catalyst compositions and their 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 composition comprises a zeolite which comprises a MOR framework structure and a MFI and/or MEL framework structure, (b) at least one first metal of Group 10 of the IUPAC Periodic Table, and (c) optionally at least one second metal of Group 11 to 15 of the IUPAC Periodic Table. In one or more embodiments, the MOR framework structure comprises mordenite, preferably a mordenite zeolite having small particle size. The MFI framework structure preferably comprises ZSM-5, and the MEL framework structure preferably comprises ZSM-11.

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 catalyst compositions and their 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 composition comprises a zeolite which comprises a MOR framework structure and a MFI and/or MEL framework structure, (b) at least one first metal of Group 10 of the IUPAC Periodic Table, and (c) optionally at least one second metal of Group 11 to 15 of the IUPAC Periodic Table. In one or more embodiments, the MOR framework structure comprises mordenite, preferably a mordenite zeolite having small particle size. The MFI framework structure preferably comprises ZSM-5, and the MEL framework structure preferably comprises ZSM-11.

A method for producing double-component modified molecular sieve comprises adding molecular sieve to an aqueous solution containing phosphorus to form a mixture, allowing the mixture to react at pH of 1-10, temperature of 70-200 C. and pressure of 0.2-1.2 MPa for 10-200 min, and then filtering, drying and baking the resultant to obtain phosphorus-modified molecular sieve, and then adding the phosphorus-modified molecular sieve to an aqueous solution containing silver ions, allowing the phosphorus-modified molecular sieve to react with silver ions at 0-100 C. in dark condition for 30-150 min, and then filtering, drying and baking. The obtained double-component modified molecular sieve contains 88-99 wt % molecular sieve with a ratio of silica to alumina between 15 and 60, 0.5-10 wt % phosphorus (based on oxides) and 0.01-2 wt % silver (based on oxides), all based on dry matter. A catalyst produced from the double-component modified molecular sieve has improved hydrothermal stability and microactivity.

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.

A catalyst for the carbonylation of dimethyl ether to methyl acetate. The catalyst comprises a zeolite, such as a mordenite zeolite, at least one Group IB metal, such as copper, and/or at least one Group VIII metal, such as iron, and at least one Group IIB metal, such as zinc. Such a catalyst with combined metals provides enhanced catalytic activity, improved stability, and improved selectivity to methyl acetate, and does not require a halogen promoter, as compared to a metal-free or copper only zeolite.

A catalyst composition for isomerization of paraffins includes at least one metal, at least one heteropoly acid and a support material. Further provided are a process for preparation of the catalyst composition and a process for isomerization of paraffins using the catalytic composition.

A catalyst and a preparation method thereof, the catalyst providing a high production yield of C8 aromatic hydrocarbons in the conversion of a feedstock containing alkyl aromatics to C8 aromatic hydrocarbons such as mixed xylene through at least one of disproportionation, transalkylation, and dealkylation while reducing a content of ethylbenzene in the product.