Abstract: The preparation of zeolite bound zeolite comprising zeolite core crystals other than MFI structure zeolite which are bound by MFI structure type zeolite and the use of the zeolite bound by MFI structure type zeolite prepared by the process as an adsorbent or as a catalyst for hydrocarbon conversion. The zeolite bound zeolite is produced by including seed crystals of MFI structure type zeolite into the silica bound aggregate forming mixture and then converting the silica binder of the aggregate to the MFI binder crystals. The resulting zeolite bound zeolite has good strength and integrity.

Abstract: A synthetic porous crystalline material has the structure of ZSM-5 and a composition involving the molar relationship:

Abstract: A process for producing isopropyl aromatics using a transalkylation reaction zone and an alkylation reaction zone is disclosed. Portions of the transalkylation reaction zone effluent pass to a multibed alkylation reaction zone where aromatics in the transalkylation reaction zone effluent are alkylated to the desired isopropyl aromatics. At least a portion of the transalkylation reaction zone effluent passes to an alkylation bed other than the first alkylation bed of the multibed alkylation reaction zone. This process decreases the capital and operating costs of recycling the aromatics in the transalkylation reaction zone effluent. This process is well suited for solid transalkylation and alkylation catalysts. Cumene may be produced by this process.

Abstract: A process is disclosed for improving the yield in the production of high octane gasoline after naphtha reforming by utilizing a transalkylation step to upgrade the heavy and light fractions coming from the reforming step.

Abstract: There is provided a process for converting hydrocarbons which utilizes a zeolite bound zeolite catalyst that has enhanced performance when utilized in hydrocarbon conversion processes, e.g., catalytic cracking, alkylation, disproportionation of toluene, isomerization, and transalkylation reactions. The catalyst comprises a first zeolite having particles of greater than about 0.1 micron average particle size and a binder comprising second zeolite particles having an average particle size less than said first particles.

Abstract: A process for producing ethyl aromatics using a transalkylation reaction zone and an alkylation reaction zone is disclosed. Portions of the transalkylation reaction zone effluent pass to a multibed alkylation reaction zone where aromatics in the transalkylation reaction zone effluent are alkylated to the desired ethyl aromatics. At least a portion of the transalkylation reaction zone effluent passes to an alkylation bed other than the first alkylation bed of the multibed alkylation reaction zone. This process decreases the capital and operating costs of recycling the aromatics in the transalkylation reaction zone effluent. This process is well suited for solid transalkylation and alkylation catalysts. Ethylbenzene may be produced by this process.

Abstract: Process for the production of ethylbenzene by alkylation over a silicalite alkylation catalyst with subsequent transalkylation of diethylbenzene with the alkylation catalyst and conditions selected to retard xylene production and also heavies production. Benzene and ethylene are applied to a multi-stage alkylation reaction zone having a plurality of series-connected catalyst beds containing silicalite of a predominantly monoclinic symmetry having a silica/alumina ratio of at least 275. Gas-phase ethylation of benzene is at a flow rate to provide a space velocity of benzene over the catalyst to produce a xylene concentration of about 600 ppm or less of the ethylbenzene content. Periodically the space velocity may be increased to a value which is greater than the space velocity associated with a minimum concentration of diethylbenzene in the alkylation product such that diethylbenzene production is enhanced while minimizing any attendant transalkylation reactions within the alkylation reaction zone.

Abstract: There is provided a process for producing high-purity meta-xylene by converting a hydrocarbon feedstream comprising at least about 5 wt % ethylbenzene and at least about 20 wt % meta-xylene, over a single molecular sieve catalyst under ethylbenzene conversion conditions sufficient to provide a primary product stream depleted of more than 50% of the ethylbenzene present in the feedstream. The process can further comprise stripping benzene and/or toluene by-products from the primary product stream to provide a secondary product stream comprising at least about 75 wt % mixed ortho-xylene and meta-xylene; and splitting the secondary product stream by removing substantially all of the ortho-xylene present therein to provide a tertiary product stream comprising at least about 95 wt % meta-xylene.

Abstract: There is provided a process for converting hydrocarbons which utilizes a zeolite bound zeolite catalyst that has enhanced performance when utilized in hydrocarbon conversion processes, e.g., catalytic cracking, alkylation, disproportionation of toluene, isomerization, and transalkylation reactions. The catalyst comprises a first zeolite having particles of greater than about 0.1 micron average particle size and a binder comprising second zeolite particles having an average particle size less than said first particles.

Abstract: An improved process is disclosed for the selective disproportionation of toluene. The process uses a zeolitic catalyst which is selectively precoked prior to toluene disproportionation in a manner to avoid a large temperature rise across a bed of the catalyst during precoking. The catalyst and process provide enhanced selectivity for the production of paraxylene.

Abstract: A process for converting hydrocarbons by contacting a hydrocarbon feedstream under hydrocarbon conversion conditions with a large crystal zeolite catalyst. The large crystal zeolite of the catalyst used in the hydrocarbon conversion process is made by heating an aqueous zeolite synthesis mixture under agitation to a temperature equal to or less than the effective nucleation temperature of the synthesis mixture. After this step, the aqueous synthesis mixture is heated in the absence of agitation to a temperature equal to or greater than the effective nucleation temperature of the aqueous zeolite synthesis mixture. The process finds particular application in hydrocarbon conversion processes where reduced non-selective acidity is important for reaction selectivity and/or the maintenance of catalyst activity, e.g., toluene disproportionation, dealkylation, alkylation, and transalkylation.

Abstract: A separation arrangement for a cumene process that operates with a relatively wet feed to an alkylation zone and relatively dry feed to a transalkylation zone reduces utilities and capital expenses for the separation and recycle of distinct wet and dry components by using an arrangement that first separates effluent from the trans alkylation and alkylation reaction zone in a benzene column before performing light ends and drying in a downstream depropanizer column. The arrangement uses a portion of the net overhead stream from the benzene column as a wet recycle stream for return to the alkylation reaction zone and sends another portion of the benzene net overhead to the depropanizer to supply a dry benzene recycle for the trans alkylation reaction zone.

Abstract: A highly selective process is described for preparing 2,6-dimethylnaphthalene which comprises reacting a naphthalene hydrocarbon selected from naphthalene, methylnaphthalenes, dimethylnaphthalenes, trimethylnaphthalenes, polymethylnaphthalenes or their mixtures with one or more benzene hydrocarbons selected from benzene, toluene, xylenes, trimethylbenzenes, tetramethylbenzenes, pentamethylbenzene and/or hexamethylbenzene, under at least partially liquid phase conditions, in the presence of a zeolite belonging to the structural type MTW and optionally in the presence of a methylating agent.

Abstract: A process for reducing the amount of undesirable byproducts, for example multi-ring compounds known as heavy residue in a process for the alkylation of an aromatic hydrocarbon with an olefin using a silicalite catalyst is disclosed. The process comprises supplying a feedstock containing benzene to a reaction zone with an alkylating agent in a molar ratio of benzene to alkylating agent of from about 2:1 to about 20:1 and into contact with an aluminosilicate alkylation catalyst having an average crystallite size of less than about 0.50 .mu.m and wherein the size of about 90% of the crystallites is less than 0.70 .mu.m. The catalyst is characterized by an Si/Al atomic ratio in the range from between 50 and 150 and a maximum pore size in the range from about 1000 to 1800 .ANG.. The catalyst has a sodium content of less than about 50 ppm and the reaction is carried out under conversion conditions including a temperature of from about 250.degree. C. to about 550.degree. C.

Abstract: An improved process combination is disclosed for the selective disproportionation of toluene. The combination comprises selective hydrogenation of a toluene feedstock followed by disproportionation using a zeolitic catalyst which is oil-dropped in an aluminum phosphate binder to achieve a high yield of paraxylene. Optionally, the catalyst is selectively precoked prior to toluene disproportionation. The catalyst and process provide improved selectivity for the production of paraxylene.

Abstract: A process is provided for the alkylation, transalkylation, or isomerization of aromatic hydrocarbons. The processes comprises contacting aromatic hydrocarbons under conversion conditions with a zeolite bound zeolite catalyst. The zeolite bound zeolite catalyst comprises first crystals of a first large pore zeolite which are bound together by second crystals of a second zeolite.

Abstract: A process for producing alkyl aromatics using a transalkylation reaction zone and an alkylation reaction zone is disclosed. The transalkylation reaction zone effluent passes to the alkylation reaction zone where aromatics in the transalkylation reaction zone effluent are alkylated to the desired alkyl aromatics. This process decreases the capital and operating costs of recycling the aromatics in the transalkylation reaction zone effluent. This process is well suited for solid transalkylation and alkylation catalysts. Ethylbenzene and cumene may be produced by this process.

Abstract: An improved zeolite catalyst containing a zeolite and a zinc component manufactured by a novel method having certain process steps necessary for providing the improved zeolite catalyst. The process steps include incorporation of a zinc component with such zeolite followed by a steam treatment. An acid treatment can be conducted after the steam treatment. Processes are also disclosed for using the improved zeolite catalyst in the conversion of hydrocarbons, preferably non-aromatic hydrocarbons, to lower olefins (such as ethylene, propylene, and butene) and aromatic hydrocarbons (such as benzene, toluene, and xylene).

Abstract: A catalytic composition is described for the alkylation or transalkylation of aromatic compounds consisting of zeolite Beta, as such or modified by the isomorphic substitution of aluminium with boron, iron or gallium or by the introduction of alkaline/earth-alkaline metals following ion exchange processes, and of an inorganic ligand, wherein the extrazeolite porosity, i.e. the porosity obtained by adding the mesoporosity and macroporosity fractions present in the catalytic composition itself, is such as to be composed for a fraction of at least 25% of pores with a radius higher than 100 .ANG..

Abstract: The present invention relates to new crystalline zeolite SSZ-48 prepared using a decahydroquinolinium cation templating agent.

Abstract: A catalyst, method for preparing the catalyst, and method for using the catalyst having improved para-selectivity in the conversion of alkyl-substituted benzene to para-dialkyl-substituted benzene. The catalyst being prepared by calcining a starting zeolite material, selectivating the calcined zeolite using a silicon-containing selectivating agent, physically mixing the calcined and selectivated zeolite with a binder, shaping the resulting zeolitic physical blend into a form suitable for use in a hydrocarbon conversion process, selectivating the shaped zeolitic physical blend using a silicon-containing selectivating agent, and calcining the selectivated shaped zeolitic physical blend.

Abstract: An improved catalyst and process are disclosed for the selective disproportionation of toluene. The process uses a zeolitic catalyst which is oil-dropped in an aluminum phosphate binder and has an X-ray diffraction pattern showing characteristic intensities at specified Bragg angles. Optionally, the catalyst is selectively precoked prior to toluene disproportionation. The catalyst and process provide improved selectivity for the production of paraxylene.

Abstract: A supported Lewis acid catalyst system for catalyzing hydrocarbon conversion reactions including cationic polymerization, alkylation, isomerization and cracking reactions is disclosed, wherein the catalyst system comprises an inorganic oxide support having immobilized thereon a least one strong Lewis acid comprising at least one metal salt of a strong Bronsted acid wherein the metal is selected from the group consisting of aluminum, boron gallium, antimony, tantalum, niobium, yttrium, cobalt, nickel, iron, tin, zinc, magnesium barium strontium, calcium, tungsten, molybdenum and the metals of the lanthanide series and wherein the strong Bronsted acid is selected from the group consisting of mineral and organic acids stronger than 100% sulfuric acid.

Abstract: This invention relates to a new synthetic porous crystalline material, designated MCM-68, a method and novel polycyclic organic cation for its preparation and its use in catalytic conversion of organic compounds. The new crystalline material exhibits a distinctive X-ray diffraction pattern and has a unique crystal structure which contains at least one channel system, in which each channel is defined by a 12-membered ring of tetrahedrally coordinated atoms, and at least two further, independent channel systems, in each of which each channel is defined by a 10-membered ring of tetrahedrally coordinated atoms, wherein the number of unique 10-membered ring channels is twice the number of 12-membered ring channels.

Abstract: Reduction of the amount of 1,1-diphenylethane formed in the production of ethylbenzene by alkylation of benzene with ethylene and by transalkylation of benzene with polyethylbenzenes can be effected by reacting at a low concentration of ethylene. This invention allows operation at a low molar ratio of phenyl groups per ethyl group and leads to a product containing less than 1.0 wt-% 1,1-diphenylethane relative to ethylbenzene. This invention is applicable to processes for the production of a wide variety of other commercially important alkylated aromatics.

Abstract: Aromatic hydrocarbons are efficiently converted by bringing feedstock containing from 5 to 50% by weight of an aromatic hydrocarbon having an ethyl group and a C.sub.9 alkyl aromatic hydrocarbon into contact with a catalyst capable of disproportionation, trans-alkylation and dealkylation, a secondary particle diameter of a zeolite in the catalyst being 10 .mu.m or less.

Abstract: There is provided a process for converting hydrocarbons which utilizes a zeolite bound zeolite catalyst that has enhanced performance when utilized in hydrocarbon conversion processes, e.g., catalytic cracking, alkylation, disproportionation of toluene, isomerization, and transalkylation reactions. The catalyst comprises a first zeolite having particles of greater than about 0.1 micron average particle size and a binder comprising second zeolite particles having an average particle size less than said first particles.

Abstract: A catalytic composition is described for the alkylation and/or transalkylation of aromatic hydrocarbons consisting of beta zeolite, as such or modified by the isomorphous substitution of aluminum with boron, iron or gallium or by the introduction of alkaline and/or earth alkaline metals following an ion-exchange process, and an inorganic ligand, wherein the extrazeolite porosity, i.e. the porosity obtained by adding the mesoporosity and macroporosity fractions present in the catalytic composition itself, is such that a fraction of at least 25% is composed of pores with a radius higher than 100 .ANG., said composition being characterized by a total volume of extrazeolitic pores greater than or equal to 0.80 ml/g.

Abstract: The invention concerns NU-88 zeolite, characterized by:i) a chemical composition with the following formula, expressed in terms of the mole ratios of the oxides for the anhydrous state:100 XO.sub.2, mY.sub.2 O.sub.3, pR.sub.2/n Owherem is 10 or less;p is 20 or less;R represents one or more cations with valency n;X represents silicon and/or germanium;Y represents one or more of the following elements: aluminium, iron, gallium, boron, titanium, vanadium, zirconium, molybdenum, arsenic, antimony, chromium and manganese; andii) an X ray diffraction diagram, in its as synthesized state, which comprises the results shown in Table 1 of the description.The invention also concerns the preparation of the zeolite, any catalyst containing the zeolite and any catalytic process using such a catalyst.

Abstract: The present invention relates to a process of preparing dialkylnaphthylenes and polyalkylenenaphthyleneates.

Abstract: Catalysts that are zeolite-based and contain tungsten carbide. A tungsten carbide/zeolite catalyst useful in the disproportionation of sulfur containing toluene. A method for preparing a tungsten carbide/zeolite catalyst. A method for disproportionation of sulfur-containing toluene in the presence of a tungsten carbide/zeolite catalyst. An acid-leached zeolite impregnated with tungsten carbide as a catalyst composition for use in converting hydrocarbons. A method for preparing a catalyst composition of acid-leached zeolite impregnated with tungsten carbide. A method for contacting a hydrocarbon feedstock with a catalyst composition of acid-leached zeolite impregnated with tungsten carbide under conditions for converting the hydrocarbons.

Abstract: A process for the conversion of heavy bottoms from aromatic alkylation known as "flux oil" and containing heavier polyalkylaromatic compounds, in which the heavier polyalkylates are fed along with aromatic to a reactor containing an acidic zeolite catalyst for conversion to light mono-, and poly alkylaromatic compounds. The light polyalkylates may then be transalkylated with benzene to form additional monoalkylate.

Abstract: 2,6-Dialkylnaphthalene is prepared from a feedstock comprising naphthalene and an alkylating agent, by a process comprising the steps:(I) transalkylating isomers of dialkylnaphthalene and naphthalene to produce monoalkylnaphthalene and isomers of dialkylnaphthalene;(II) separating the product obtained in step (I) into naphthalene, monoalkylnaphthalene, dialkylnaphthalene and other components;(III) alkylating the monoalkylnaphthalene fraction from step (II) with an alkylating agent to produce dialkylnaphthalene; and(IV) separating 2,6-dialkylnaphthalene from the dialkylnaphthalene fraction in step (II),wherein at least step (I) or step (III) is conducted in the presence of a catalyst having a composition comprising a synthetic zeolite having an X-ray diffraction pattern with an interplanar d-spacing (.ANG.)______________________________________ 12.36 .+-. 0.4 11.03 .+-. 0.2 8.83 .+-. 0.14 6.18 .+-. 0.12 6.00 .+-. 0.10 4.06 .+-. 0.07 3.91 .+-. 0.07 3.42 .+-. 0.06.

Abstract: A process for the transalkylation of benzene, toluene and alkylaromatic hydrocarbons containing nine and ten carbon atoms form alkylaromatic hydrocarbons containing eight carbon atoms has been developed. The fixed bed reaction and adsorption zone contains a transalkylation catalyst and an adsorbent effective to selectively adsorb C.sub.9 and C.sub.10 alkylaromatic hydrocarbon reactants relative to the C.sub.8 alkylaromatic hydrocarbon products. Hydrogen and a desorbent are introduced to a first portion of the zone and an effluent containing at least one C.sub.8 alkylaromatic hydrocarbon product is withdrawn from a second portion of the zone. After a period of time, the desorbent is redirected to the second portion of the zone and concurrently the effluent containing at least one C.sub.8 alkylaromatic hydrocarbon product is withdrawn from the first portion of the zone.

Abstract: An improved process is disclosed for the selective disproportionation and transalkylation of toluene. The process uses a zeolitic catalyst, preferably comprising a binder, containing a weak metal in a defined reduced state which is believed to provide Lewis acidity in the catalyst. The catalyst and process provide improved selectivity for the production of paraxylene.

Abstract: A process is described for preparing monoalkylated aromatic compounds which comprises subjecting an aromatic hydrocarbon to alkylation with an olefin containing from 2 to 4 carbon atoms, or to transalkylation with a polyalkylaromatic hydrocarbon, in the presence of ERS-10 zeolite.

Abstract: A process for producing at least one C.sub.8 alkylaromatic hydrocarbon product from a feedstock containing at least one C.sub.9 or C.sub.10 alkylaromatic hydrocarbon reactant using simulated moving bed reactive chromatography has been developed. At least a portion of the reactants are transalkylated to form at least one product in a zone of the simulated moving bed with concurrent separation of at least one alkylaromatic hydrocarbon using the adsorbent. The adsorbed alkylaromatic hydrocarbon is desorbed from the adsorbent in a subsequent zone of the simulated moving bed and the transalkylation of the reactants with concurrent separation of at least one alkylaromatic hydrocarbon using the adsorbent is continued.

Abstract: A novel catalyst for the conversion of hydrocarbons comprising a material containing an acid treated zeolite, a boron component and a zinc component wherein the material is treated with a silylating agent. A method of making such novel catalyst and the use of the novel catalyst for converting paraffin hydrocarbons with a low rate of coke formation during such conversion are disclosed.

Abstract: A separation arrangement for a cumene process that operates with a relatively wet feed to an alkylation zone and relatively dry feed to a transalkylation zone reduces utilities and capital expenses for the separation and recycle of distinct wet and dry components by using an arrangement that first separates effluent from the trans alkylation and alkylation reaction zone in a benzene column before performing light ends and drying in a downstream depropanizer column. The arrangement uses a portion of the net overhead stream from the benzene column as a wet recycle stream for return to the alkylation reaction zone and sends another portion of the benzene net overhead to the depropanizer to supply a dry benzene recycle for the trans alkylation reaction zone.

Abstract: There is provided a catalyst comprising ZSM-5, rhenium which is impregnated onto the catalyst, and a selectivating agent. The selectivating agent may be coke and/or a siliceous material. The catalyst is particularly useful for catalyzing toluene disproportionation reactions. Methods for making this catalyst and processes for using this catalyst in toluene disproportionation are also provided.

Abstract: There is provided a process for shape selective xylene disproportionation that involves contacting a feedstream which includes xylene under conversion conditions, with a molecular sieve catalyst that has been surface modified. The xylene disproportionation process has a selectivity for pseudocumene of over 85%.

Abstract: The invention concerns a catalyst comprising at least one matrix and at least one zeolite of structure type mazzite, preferably omega zeolite, comprising silicon and aluminium, at least partially, preferably practically completely in its acid form, said zeolite having been prepared by dealuminization of the framework, by means of at least one treatment using at least one solution of a fluorosilicate of a cation in a proportion of 0.05 to 5 moles per mole of aluminium contained in the dry zeolite, said catalyst optionally comprising at least one element selected from groups IB and VIII of the periodic classification of the elements. The invention also concerns the use of said catalyst for the dismutation of alkylaromatic hydrocarbons, and preferably for the dismutation of toluene to produce benzene and xylenes, and/or for the transalkylation of alkylaromatic hydrocarbons, preferably for the transalkylation of toluene and trimethylbenzenes to produce xylenes.

Abstract: A novel zeolite catalyst comprising an acid treated zeolite impregnated with silver and boron, a method of making such zeolite catalyst, and the use thereof for converting paraffin hydrocarbons to olefins and aromatics.

Abstract: A catalyst composition and a process for converting a hydrocarbon stream such as, for example, gasoline to olefins and C.sub.6 to C.sub.8 aromatic hydrocarbons such as toluene and xylenes are disclosed. The catalyst composition comprises a zeolite, a binder, and boron wherein the weight of boron is in the range of from about 0.01 to about 10 weight %. The process comprises contacting a hydrocarbon stream with the catalyst composition under a condition sufficient to effect the conversion of a hydrocarbon to an olefin and a C.sub.6 to C.sub.8 aromatic hydrocarbon. Also disclosed is a process for producing the catalyst composition which comprises: (1) combining a zeolite with a coke-reducing amount of a binder under a condition effective to produce a zeolite-binder mixture; (2) contacting said zeolite-binder mixture with coke-reducing amount of a boron compound under a condition effective to produce a boron-incorporated or -impregnated zeolite; and (3) calcining the boron-incorporated or -impregnated zeolite.

Abstract: A catalyst composition, a process for producing the composition and a process for transalkylation of C.sub.9 + aromatic compounds to C.sub.6 to C.sub.8 aromatic hydrocarbons are disclosed. The composition comprises a zeolite and tungsten wherein tungsten is preferably present as tungsten carbide which is impregnated on the zeolite. A preferred process for producing the catalyst composition which comprises: (1) contacting a zeolite with an effective amount of an acid under a condition sufficient to produce an acid-leached zeolite; and (2) impregnating acid-leached zeolite with an effective amount of tungsten-containing compound under a condition sufficient to effect the production of a tungsten carbide-promoted zeolite. The transalkylation process comprises contacting, in the presence of the catalyst composition, a fluid which comprises a C.sub.9 + aromatic compound with a hydrogen-containing fluid under a condition sufficient to effect the conversion of a C.sub.9 + aromatic compound to a C.sub.6 to C.sub.

Abstract: The present invention relates to new crystalline zeolite SSZ-43 prepared using a substituted piperidinium or decahydroquinolinium cation templating agent.

Abstract: A zeolite-based ethylbenzene process which is suitable for retrofitting aluminum chloride-based ethylbenzene plants. The process involves alkylating benzene with ethylene in an alkylation zone in the presence of zeolite beta or Y or an MCM zeolite so as to produce an alkylation product mixture containing benzene, ethylbenzene, and polyethylbenzenes which can be separated in the aromatics recovery (distillation) stage of an aluminum chloride-based plant. The polyethylbenzenes are subsequently contacted with benzene in a transalkylation zone using zeolite beta or mordenite or Y so as to produce a transalkylation product mixture which is also separable in the aromatics recovery stage of an aluminum chloride-based plant.

Abstract: An alkylation/transalkylation process involving vapor phase alkylation of a benzene feedstock in a multi-stage alkylation zone having a plurality of series connected catalyst beds containing a pentasil aromatic alkylation catalyst, such as silicalite, coupled with intermediate separation and recirculation steps and liquid phase transalkylation over a transalkylation catalyst comprising a molecular sieve having a pore size greater than the pore size of the silicalite. The benzene containing feedstock is supplied to the multi-stage alkylation reaction zone along with a C.sub.2 -C.sub.4 alkylating agent operated under temperature and pressure conditions to maintain the benzene in the gas phase. Alkylated product is recovered from the alkylation zone and supplied to a benzene recovery zone for the separation of the benzene from the alkylation product. Benzene from the benzene recovery zone is recycled to the reaction zone.

Abstract: This invention is an improved process for the conversion of a C.sub.9 mixed alkyl aromatic feedstream containing ethyl substituted aromatics to a product rich in toluenes and/or xylenes via catalytic transalkylation/disproportionation using a palladium loaded moderately, dealuminated mordenite catalyst in the presence of added hydrogen and benzene.

Abstract: A gas phase, aromatics transalkylation process that comprises contacting a stream containing aromatic hydrocarbons with a catalyst comprising a zeolite selected from the group consisting of SSZ-26, Al-SSZ-33, CIT-1, SSZ-35, and SSZ-44 in the presence of added hydrogen and in the gas phase, to produce transalkylated product. The aromatics stream comprises one or more aromatic hydrocarbons, one of the hydrocarbons having at least one alkyl group attached thereto, the alkyl group comprising a C1, C2, C3 or C4 hydrocarbyl group. A preferred aromatics transalkylation process comprises contacting toluene or benzene or a mixture thereof with a stream containing trimethylbenzene in the presence of added hydrogen. The catalyst preferably contains a mild hydrogenation metal, such as nickel or palladium.