Para-xylene is separated from a mixture of xylenes and ethylbenzene by a separation process. An ortho-selective adsorbent is used to reduce the ortho-xylene concentration of the xylenes, prior to contact of the xylenes and ethylbenzene with a para-selective adsorbent. The stream rich in ortho-xylene may be isomerized in the liquid phase to increase the amount of para-xylene therein. The para-xylene-depleted stream may be treated in the vapor phase to remove the ethylbenzene and then subjected to isomerization in the liquid phase to produce a stream having a higher than equilibrium amount of para-xylene.

In a process for producing one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4), a feed comprising toluene is contacted with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction product comprising (methylcyclohexyl)toluene. At least part of the hydroalkylation reaction product is dehydrogenated in the presence of a dehydrogenation catalyst under conditions effective to produce a dehydrogenation reaction product comprising dimethyl biphenyl isomers. The dehydrogenation reaction product is then separated into at least a first stream comprising one or more 3,3-, 3,4- and 4,4-dimethyl biphenyl isomers and at least one second stream comprising one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4). The at least one second stream is then contacted with a first adsorbent thereby selectively adsorbing one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4) within said first adsorbent and then withdrawing from said first adsorbent a first extract stream comprising one or more selectively adsorbed 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4) and a first raffinate stream comprising one or more less selectively adsorbed components.

In a process for producing one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4), a feed comprising toluene is contacted with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction product comprising (methylcyclohexyl)toluene. At least part of the hydroalkylation reaction product is dehydrogenated in the presence of a dehydrogenation catalyst under conditions effective to produce a dehydrogenation reaction product comprising dimethyl biphenyl isomers. The dehydrogenation reaction product is then separated into at least a first stream comprising one or more 3,3-, 3,4- and 4,4-dimethyl biphenyl isomers and at least one second stream comprising one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4). The at least one second stream is then contacted with a first adsorbent thereby selectively adsorbing one or more 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4) within said first adsorbent and then withdrawing from said first adsorbent a first extract stream comprising one or more selectively adsorbed 2,X-dimethyl biphenyl isomers (where X=2, 3 or 4) and a first raffinate stream comprising one or more less selectively adsorbed components.

The invention relates to treating a molecular sieve prepared by at least one in situ selectivation sequence wherein graphitic coke is adhered to said molecular sieve, which is useful in a toluene disproportionation process.

Process and apparatuses for producing benzene and para-xylene from a reformate stream is provided. The process comprises separating the reformate stream to provide a first stream comprising C.sub.4 and lighter hydrocarbons and a second stream comprising aromatic hydrocarbons. The second steam is provided to a reformate splitter to provide a reformate bottoms stream comprising C.sub.8+ aromatic hydrocarbons and a reformate overhead stream comprising C.sub.7 aromatic hydrocarbons. The reformate overhead stream is passed to an aromatics extraction unit to provide an aromatics extract stream comprising benzene and toluene and a raffinate stream comprising non-aromatic hydrocarbons. The reformate bottoms stream and one of the first stream and the raffinate stream is passed to an olefin reduction zone, wherein the reformate bottoms stream and one of the first stream and the raffinate stream are contacted with an olefin saturation catalyst under olefin saturation conditions to produce an olefin-treated reformate stream.

A process for the production of high purity toluene and para-xylene is described. More specifically, the process involves the production of high purity toluene produced via a light-desorbent selective adsorption process for para-xylene production, such as light desorbent para-xylene extraction, without the need for dedicated solvent extraction or olefin removal from the toluene stream.

A process for the production of high purity toluene and para-xylene is described. More specifically, the process involves the production of high purity toluene produced via a light-desorbent selective adsorption process for para-xylene production, such as light desorbent para-xylene extraction, without the need for dedicated solvent extraction or olefin removal from the toluene stream.

Methods and alternatives for the efficient and cost-effective production of high-octane fuel blends from C9 aromatic feeds including methyl benzenes and C2 and/or higher alkyl benzenes. The fuel blend can serve as a high-octane unleaded fuel or fuel blending component for a wide range of applications, particularly aviation gasoline and other high-performance transportation fuels.

Methods and alternatives for the efficient and cost-effective production of high-octane fuel blends from C9 aromatic feeds including methyl benzenes and C2 and/or higher alkyl benzenes. The fuel blend can serve as a high-octane unleaded fuel or fuel blending component for a wide range of applications, particularly aviation gasoline and other high-performance transportation fuels.

Embodiments include processes and systems for maximizing the production of benzene and para-xylene from heavy reformate. Embodiments include a C9 dealkylation reactor, a transalkylation reactor, and a C10+ dealkylation reactor. The process and system for producing benzene and para-xylene may be configured to additionally produce alkanes in the presence of hydrogen or olefins in the absence of hydrogen. Embodiments may include an aromatic extraction unit to separate non-aromatics from aromatics.