A transalkylation process co-feeds benzene at a relatively high proportion with C9+ aromatics in a feed stream to a transalkylation reactor. At lower proportions (≤5 wt %) of benzene, ring loss is greater for benzene than toluene and ring loss is increased by increasing the proportion of benzene in the feed stream. When the benzene is co-fed in a proportion sufficiently greater than 5 weight percent of the feed stream, ring loss is unexpectedly reduced.

The present invention relates to a catalyst for isomerization of alkylated aromatics such as mixed xylenes, using xylene isomerization catalyst particles including post-framework modified USY zeolite in which zirconium atoms and/or titanium atoms and/or hafnium atoms form a part of a framework of an ultra-stable Y-type zeolite.

Systems and methods are provided for integration of an aromatic formation process for converting non-aromatic hydrocarbon to an aromatic product and subsequent methylating of a portion of the aromatic product to produce a methylated product, with improvements in the aromatic formation process and/or the methylation process based on integrating portions of the secondary processing trains associated with the aromatic formation process and the methylation process. The aromatic formation process and methylation process can be used, for example, for integrated production of specialty aromatics or gasoline blending components.

Systems and methods are provided for integration of an aromatic formation process for converting non-aromatic hydrocarbon to an aromatic product and subsequent methylating of a portion of the aromatic product to produce a methylated product, with improvements in the aromatic formation process and/or the methylation process based on integrating portions of the secondary processing trains associated with the aromatic formation process and the methylation process. The aromatic formation process and methylation process can be used, for example, for integrated production of specialty aromatics or gasoline blending components.

A method of producing p-xylene, the method comprising the steps of converting the C9+ aromatic hydrocarbons and the hydrogen gas in the presence of a dealkylation catalyst to produce a dealkylation effluent, separating the dealkylation effluent to produce a carbon-nine (C9) aromatics stream, a xylene stream, and a toluene stream, separating the p-xylenes from the xylene stream in the p-xylene separation unit to produce a p-xylene product and a p-xylene depleted stream, converting the m-xylene and o-xylene in the p-xylene depleted stream in the isomerization unit to produce an isomerization effluent, reacting the C9 aromatics stream and the hydrogen stream in the presence of a transalkylation catalyst in the transalkylation reactor to produce a transalkylation effluent, separating the C6 to C9+ aromatic hydrocarbons in the isomerization effluent and the transalkylation effluent in the splitter column to produce a benzene recycle, a toluene recycle, a xylene recycle and a C9+ recycle.

Disclosed are a process and system that are capable of performing selective hydrogenation on aromatic fractions by configuring a catalyst bed through staged loading of a plurality of hydrogenation catalysts with different catalytic properties, or configuring a catalyst system in which a plurality of hydrogenation catalysts are arranged using a plurality of reactors in such a way as to be equivalent with the staged loading, and as a result, are capable of suppressing aromatic loss while improving the selective removal of unsaturated hydrocarbons in the aromatic fraction and durability compared to the case of using a single catalyst.

Disclosed are a process and system that are capable of performing selective hydrogenation on aromatic fractions by configuring a catalyst bed through staged loading of a plurality of hydrogenation catalysts with different catalytic properties, or configuring a catalyst system in which a plurality of hydrogenation catalysts are arranged using a plurality of reactors in such a way as to be equivalent with the staged loading, and as a result, are capable of suppressing aromatic loss while improving the selective removal of unsaturated hydrocarbons in the aromatic fraction and durability compared to the case of using a single catalyst.

Processes for the catalytic activation and/or dehydrogenation of a paraffin feed stream that is enriched in C5 alkanes to produce olefins that are then hydrated in the presence of water to produce C5 alcohols. Optionally, paraffin isomers are separated and the n-paraffins isomerized prior to catalytic activation and/or dehydrogenation.

A method of recovering paraxylene in a pressure swing adsorption unit with varying hydrogen purge pressures. The pressure swing adsorption zone is adapted to adsorb and desorb paraxylene based on the cycling of partial pressure in the zone. A first hydrogen purge is fed concurrent to the feed. A second hydrogen purge is countercurrent to the feed.

A method of recovering paraxylene in a pressure swing adsorption unit with varying hydrogen purge pressures. The pressure swing adsorption zone is adapted to adsorb and desorb paraxylene based on the cycling of partial pressure in the zone. A first hydrogen purge is fed concurrent to the feed. A second hydrogen purge is countercurrent to the feed.