The invention relates to a catalyst composition which comprises a carrier material component and at least one metal component that is supported on the carrier material component. The carrier material component comprises a ZSM-12 type zeolite, a EU-1 type zeolite, and an inorganic binder. The metal component may include a Group VIII metal. The invention further relates to a process for preparing the catalyst and using it in a process for the isomerisation of alkylaromatics.

A method for generating isobutene, for isomerizing normal butene to isobutene, in which generation of by-products can be infinitely suppressed, and a high yield of isobutene can be achieved. The method for generating isobutene includes isomerizing normal butene to isobutene. In isomerizing, the normal butene is brought into contact with zeolite, and a reaction temperature in isomerizing is in a range from 25? C. to 249? C.

Novel MEL framework type zeolites can be made to have small crystallite sizes and desirable silica/SiO.sub.2 molar ratios. Catalyst compositions comprising such MEL framework type zeolites can be particularly advantageous in isomerization C8 aromatic mixtures. An isomerization process for converting C8 aromatic hydrocarbons can advantageously utilize a catalyst composition comprising a MEL framework type zeolite.

Novel MEL framework type zeolites can be made to have small crystallite sizes and desirable silica/SiO.sub.2 molar ratios. Catalyst compositions comprising such MEL framework type zeolites can be particularly advantageous in isomerization C8 aromatic mixtures. An isomerization process for converting C8 aromatic hydrocarbons can advantageously utilize a catalyst composition comprising a MEL framework type zeolite.

The present invention relates to a method for converting a feed mixture comprising an aromatic C8 mixture of xylenes and ethylbenzene in which the para-xylene content of the xylene portion of the feed is less than equilibrium to produce a product mixture of reduced ethylbenzene content and a greater amount of para-xylene, which method comprises contacting the feed mixture at conversion conditions with a first catalyst having activity for the conversion of ethylbenzene, and with a second catalyst having activity for the isomerization of a xylene.

The present invention relates to a method for converting a feed mixture comprising an aromatic C8 mixture of xylenes and ethylbenzene in which the para-xylene content of the xylene portion of the feed is less than equilibrium to produce a product mixture of reduced ethylbenzene content and a greater amount of para-xylene, which method comprises contacting the feed mixture at conversion conditions with a first catalyst having activity for the conversion of ethylbenzene, and with a second catalyst having activity for the isomerization of a xylene.

A catalyst system is disclosed for producing para-xylene from a C.sub.8 hydrocarbon mixture comprising ethylbenzene and at least one xylene isomer other than para-xylene. The catalyst system comprises a first catalyst bed and a second catalyst bed. The first catalyst bed comprises a first zeolite and a rhenium hydrogenation component. The first zeolite has a constraint index from 1 to 12, an average crystal size from 0.1 to 1 micron and has been selectivated to have an ortho-xylene sorption time of greater than 1200 minutes based on its capacity to sorb 30% of the equilibrium capacity of ortho-xylene at 120? C. and an ortho-xylene partial pressure of 4.5?0.8 mm of mercury. The second catalyst bed comprises a second zeolite and a rhenium hydrogenation component. The second zeolite has a constraint index ranging from 1 to 12 and an average crystal size of less than 0.1 micron.

A catalyst system is disclosed for producing para-xylene from a C.sub.8 hydrocarbon mixture comprising ethylbenzene and at least one xylene isomer other than para-xylene. The catalyst system comprises a first catalyst bed and a second catalyst bed. The first catalyst bed comprises a first zeolite and a rhenium hydrogenation component. The first zeolite has a constraint index from 1 to 12, an average crystal size from 0.1 to 1 micron and has been selectivated to have an ortho-xylene sorption time of greater than 1200 minutes based on its capacity to sorb 30% of the equilibrium capacity of ortho-xylene at 120? C. and an ortho-xylene partial pressure of 4.5?0.8 mm of mercury. The second catalyst bed comprises a second zeolite and a rhenium hydrogenation component. The second zeolite has a constraint index ranging from 1 to 12 and an average crystal size of less than 0.1 micron.

Catalysts are disclosed having metal oxide support structures and acidic reaction sites. The reaction sites may be according to the general formula M.sub.xO.sub.yAlBr.sub.zX].sup.H.sup.+ where x is one or two; y is one or two; z is one or two; X is selected from Br or Cl; M is Al or Si and one or more of M, O and Al has a molecular bond with the metal oxide support structure.

Catalysts are disclosed having metal oxide support structures and acidic reaction sites. The reaction sites may be according to the general formula M.sub.xO.sub.yAlBr.sub.zX].sup.H.sup.+ where x is one or two; y is one or two; z is one or two; X is selected from Br or Cl; M is Al or Si and one or more of M, O and Al has a molecular bond with the metal oxide support structure.