A process is described for producing cumene comprising contacting benzene and a C3 alkylating agent under alkylation conditions with an alkylation catalyst in an alkylation zone to produce an alkylation effluent comprising cumene and alkylaromatic compounds heavier than cumene. Cumene is recovered from the alkylation effluent to leave a byproduct stream containing the alkylaromatic compounds heavier than cumene, which is separated into a polyisopropylbenzene-containing stream, an aromatic overhead stream, and a bottoms product. At least part of the aromatic overhead stream is recycled to the alkylation zone to reduce raw material consumption and improve cumene yield.

A process is provided for utilizing polypropylene-containing waste plastic. The process provides pyrolyzing a plastic feed in a pyrolysis reactor to obtain a pyrolysis effluent stream. The process further provides passing the pyrolysis effluent stream to a distillation column to obtain a C.sub.9 hydrocarbons rich stream which is also dimethylheptenes rich and then passing the C.sub.9 hydrocarbons rich stream to a reforming unit to provide a reformate stream. The process further provides passing the reformate stream to a transalkylation unit to provide a mixed-xylenes stream.

The present disclosure relates to a material preferably used in a guard bed, and having an increased capacity to adsorb catalyst poisons, as measured by collidine update at 200° C. The material is made by a method in which it is treated by being dried with a drying gas, preferably, at a temperature greater than about 200° C. The treated material may be used to remove impurities from untreated feed streams to, for example, aromatic alkylation and transalkylation processes, where such impurities act as catalyst poisons that cause deactivation of the acidic molecular sieve-based catalysts used, thereby increasing the cycle length of such catalysts.

The present invention relates to a device and a process for converting aromatic compounds, wherein: methyl-substituted aromatic compounds are extracted from a hydrocarbon feedstock (2) comprising aromatic compounds having at least 8 carbon atoms in an extraction unit (1), to produce at least one effluent enriched in methyl-substituted aromatic compounds (3A, 3B) and an effluent depleted in methyl-substituted aromatic compounds (4); and C2+ alkyl chains of the aromatic compounds of the depleted effluent (4) are converted into methyl groups in a hydrogenolysis unit (5) placed downstream of the extraction unit (1), to produce a hydrogenolysis effluent enriched in methyl-substituted aromatic compounds (7).

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.

In a process for the synthesis of a crystalline molecular sieve material having the EUO framework type, a synthesis mixture is provided suitable for the formation of an EUO framework type molecular sieve and comprising N,N,N,N′,N′,N′-hexamethylhexanediammonium, Q, cations and a colloidal suspension of seed crystals of an EUO framework type molecular sieve. The synthesis mixture is crystallized and an EUO framework type molecular sieve in the form individual crystals and/or aggregates of crystals having an average size, d.sub.50, as measured by laser scattering, of less than 15 μm is recovered from the synthesis mixture.

A method of producing a purified mixed xylene comprising: introducing toluene and methanol to an alkylation reactor (32); reacting the toluene and the methanol in the alkylation reactor (32) to form a hydrocarbon stream (22) comprising a first mixed xylene, wherein the alkylation reactor (32) comprises an alkylation catalyst; separating the hydrocarbon stream (22) into a toluene stream (24) and a separated C.sub.8+ stream (14); introducing the toluene stream (24) to a transalkylation reactor (38) with a transalkylation catalyst to produce a transalkylated stream (17) comprising a second mixed xylene; adding the transalkylated stream (17) to the hydrocarbon stream (22); and separating a C.sub.8 product stream (19) comprising the purified mixed xylene from the separated C.sub.8+ stream (14).

A method for producing an aromatic hydrocarbon with an oxygenate as raw material, includes: i) reacting an oxygenate in at least one aromatization reactor to obtain an aromatization reaction product; ii) separating the aromatization reaction product to obtain a gas phase hydrocarbons flow X and a liquid phase hydrocarbons flow Y; iii) after removing gas and/or a part of the oxygenate from the gas phase hydrocarbons flow X, a hydrocarbons flow X1 containing a non-aromatic hydrocarbon is obtained; or after removing gas and/or a part of the oxygenate from the gas phase hydrocarbons flow X, a reaction is conducted in another aromatization reactor and a separation is conducted to obtain a flow X2 containing a non-aromatic hydrocarbon and a flow X3 containing an aromatic hydrocarbon. The flows are further treated.

The xylene isomerization process unit and the transalkylation process units are combined in the present invention. A fractionation column can be shared by the two units, reducing the capital cost of the complex. In some embodiments, a split shell fractionation column and a split separator can be used.

The xylene isomerization process unit and the transalkylation process units are combined in the present invention. A fractionation column can be shared by the two units, reducing the capital cost of the complex. In some embodiments, a split shell fractionation column and a split separator can be used.