Abstract: 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.

Abstract: Methods for the production of para-xylene include flowing a xylenes-containing stream comprising PX, meta-xylene (MX), and ortho-xylene (OX), to a first crystallization stage. In addition, the methods include lowering a temperature of the xylenes-containing stream to below the eutectic point of the xylenes-containing stream within the first crystallization stage to crystallize at least some of the PX and at least some of one of both of the MX and the OX within the xylenes-containing stream. Further, the methods include separating the xylenes-containing stream into a first crystallization effluent stream and a first filtrate stream.

Abstract: A process for producing paraxylene by the catalytic alkylation of benzene and/or toluene with methanol, which produces a para-rich mixture of xylene isomers, together with water and some light organic by-products, particularly dimethyl ether and C4? olefins. The off-gas stream, containing the C4? olefins, may be recycled back to the reaction to be co-injected with methanol to reduce the methanol self-decomposition and the reaction of methanol to olefins or to fluidize catalyst particles recovered by a reactor cyclone. By using recycled off-gas rather than water or steam, the deleterious effects of water and/or steam on the catalyst aging and activity rates and the size of downstream equipment necessary to recover olefin by-products may be reduced.

Abstract: In a process and system for treatment of feed stocks comprising alkylating agent and metal salts, the metal salts are removed from the feedstock by an efficient combination of separations processes. The processes may take place in one or more stages, each stage taking place in one or more vessels. Such treatment processes may remove 99.9% or more of metal salts from a feedstock, while recovering 99.9% or more of the alkylating agent from the feedstock for use in an alkylation reaction, especially of aromatics such as toluene and benzene. Preferred alkylating agents include methanol and mixtures of carbon monoxide and hydrogen, for methylation of toluene and/or benzene. The methylation proceeds over an aluminosilicate catalyst and preferably yields para-xylene with 75% or greater selectivity.

Abstract: A process is provided for producing xylene by transalkylation including introducing sulfur into a reactor containing a catalyst system prior to first introduction of hydrocarbon feedstock into the reactor; introducing hydrocarbon feedstock into the reactor upon the concentration of sulfur downstream of the catalyst system meeting a predetermined sulfur breakthrough concentration; continuing sulfur introduction for a period of time after first introducing hydrocarbon feedstock into the reactor; reducing the concentration of sulfur introduced upon ?T decreasing to or below a predetermined sulfur reduction threshold; and discontinuing sulfur introduction upon ?T decreasing to or below a predetermined sulfur shutoff threshold.

Abstract: Para-xylene is separated from a mixture of C8 aromatics using a simulated moving bed (SMB) adsorption process, wherein a MOF is used as an adsorbent and an alkane or alkene having 7 or less carbon atoms, such as hexane or heptane is used as desorbent. Because of the difference in boiling points of a hexane or heptane desorbent as compared to conventional desorbents such as toluene or para-diethylbenzene, less energy is required to separate hexane or heptane from C8 aromatics by distillation than the energy required to separate toluene or diethylbenzene from C8 aromatics by distillation.

Abstract: In a process for producing paraxylene, a hydrocarbon feedstock comprising benzene and/or toluene is contacted with an alkylating reagent comprising methanol and/or dimethyl ether in an alkylation reaction zone under alkylation conditions in the presence of an alkylation catalyst to produce an alkylated product comprising xylenes. The alkylation catalyst comprises a molecular sieve having a Constraint Index ?5, and the alkylation conditions comprise a temperature less than 500° C. At least part of the alkylated product is supplied to a paraxylene recovery unit to recover paraxylene and produce a paraxylene-depleted stream, which is then contacted with a xylene isomerization catalyst under conditions effective to isomerize xylenes in the paraxylene-depleted stream and produce an isomerized stream having a higher concentration of paraxylene than the paraxylene-depleted stream. At least part of the isomerized stream is then recycled to the paraxylene recovery unit to recover the paraxylene therein.

Abstract: Disclosed is a process for making para-xylene from toluene and/or benzene comprising (i) converting toluene and/or benzene to a first product mixture comprising mixed xylenes, (ii) obtaining a xylene mixture from the first product mixture, (iii) separating para-xylene from the xylene mixture, and (iv) transalkylating meta-xylene and/or ortho-xylene with toluene and/or benzene.

Abstract: Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene.

Abstract: The present invention is an improved process and apparatus for producing para-xylene, particularly with respect to a process that involves the methylation of toluene and/or benzene to selectively produce para-xylene, wherein streams having differing amounts of ethylbenzene are separately treated in the recovery of para-xylene. A first hydrocarbon feed comprising xylenes and ethylbenzene is provided to a first para-xylene adsorption section, and a second hydrocarbon feed comprising xylenes and less EB than the first hydrocarbon feed is provided to a second para-xylene adsorption section. Segregating the feeds with differing ethylbenzene contents increases the overall efficiency of the adsorption of para-xylene by the adsorption units. Efficiency and energy savings may be further improved by subjecting the lower-content ethylbenzene stream to liquid phase isomerization.

Abstract: A hydrocarbon conversion process is described. The process includes contacting in a reactor an inert gas with one or more catalyst compositions suitable for methylation of toluene and hydrogenation of phenol; contacting a reducing agent with the one or more catalyst compositions under conditions suitable for reducing metal oxide content of the catalyst composition; contacting at least part of toluene and/or benzene-containing with a oxygenate in the presence of the one or more catalyst compositions and under conditions effective to convert toluene to xylenes and produce a reactor effluent stream comprising para-xylene and having a lower concentration of phenol than the toluene-containing stream; separating at least one para-xylene-enriched stream from the reactor effluent stream; and separating from the at least one para-xylene enriched stream at least one toluene-enriched stream and at least one para-xylene-product stream. An apparatus for carrying out such a process is also described.

Abstract: Para-xylene is separated from a mixture of C8 aromatics using a simulated moving bed (SMB) adsorption process, wherein a MOF is used as an adsorbent and an alkane or alkene having 7 or less carbon atoms, such as hexane or heptane is used as desorbent. Because of the difference in boiling points of a hexane or heptane desorbent as compared to conventional desorbents such as toluene or para-diethylbenzene, less energy is required to separate hexane or heptane from C8 aromatics by distillation than the energy required to separate toluene or diethylbenzene from C8 aromatics by distillation.

Abstract: A method for the purification of an aromatic hydrocarbon process stream having phenol therein is disclosed. Aspects of the method include contacting at least a portion of the aromatic hydrocarbon process stream with a hydrogenation catalyst under hydrogenation conditions to provide a hydrogenation effluent having a lower concentration of phenol than said aromatic hydrocarbon process stream.

Abstract: A process for producing paraxylene by the catalytic alkylation of benzene and/or toluene with methanol. In prior art processes, water is typically co-injected with the methanol to improve the utilization of methanol, increase the amount of methanol that reacts with the benzene and/or toluene, and decrease the amount of methanol that decomposes to undesirable carbon monoxide, carbon dioxide, or water or reacts with itself to produce unwanted light olefinic gases. Rather than using purified methanol and co-feeding water as is taught in the prior art, crude, or unpurified, methanol that contains at least 5 wt %, such as between 5 and 35 wt %, water, based on the total amount of water and methanol feed, can be used as the alkylating agent, reducing the need to co-inject water at least partially, if not completely.

Abstract: A hydrocarbon conversion process is described. The process includes contacting in a reactor an inert gas with one or more catalyst compositions suitable for methylation of toluene and hydrogenation of phenol; contacting a reducing agent with the one or more catalyst compositions under conditions suitable for reducing metal oxide content of the catalyst composition; contacting at least part of toluene and/or benzene-containing with a oxygenate in the presence of the one or more catalyst compositions and under conditions effective to convert toluene to xylenes and produce a reactor effluent stream comprising para-xylene and having a lower concentration of phenol than the toluene-containing stream; separating at least one para-xylene-enriched stream from the reactor effluent stream; and separating from the at least one para-xylene enriched stream at least one toluene-enriched stream and at least one para-xylene-product stream. An apparatus for carrying out such a process is also described.

Abstract: Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene.

Abstract: In a process and system for treatment of feed stocks comprising alkylating agent and metal salts, the metal salts are removed from the feedstock by an efficient combination of separations processes. The processes may take place in one or more stages, each stage taking place in one or more vessels. Such treatment processes may remove 99.9% or more of metal salts from a feedstock, while recovering 99.9% or more of the alkylating agent from the feedstock for use in an alkylation reaction, especially of aromatics such as toluene and benzene. Preferred alkylating agents include methanol and mixtures of carbon monoxide and hydrogen, for methylation of toluene and/or benzene. The methylation proceeds over an aluminosilicate catalyst and preferably yields para-xylene with 75% or greater selectivity.

Abstract: A method of reducing the amount of carbon monoxide present during the metal reduction step of start-up, thus, maintaining metal dispersion and improving the metal reduction and catalyst yields. Carbon monoxide formation is minimized during the start-up procedure and during the initial catalyst dryout phase in a hydrogen-containing atmosphere, gas is purged from the reactor system, either continuously at constant pressure or by a series of pressure/depressure cycles, to remove carbon monoxide. The purging is conducted at temperatures of about 30-500° C. and pressures of about ?90-5,000 kPa(g) (?0.9-50 bar(g)). In this temperature range, carbon monoxide absorbed to the surface of the metal will desorb into the hydrogen-containing atmosphere and can be removed from the system along with carbon monoxide present in the atmosphere through the purging.

Abstract: Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene.

Abstract: In a process and system for treatment of feed stocks comprising alkylating agent and metal salts, the metal salts are removed from the feedstock by an efficient combination of separations processes. The processes may take place in one or more stages, each stage taking place in one or more vessels. Such treatment processes may remove 99.9% or more of metal salts from a feedstock, while recovering 99.9% or more of the alkylating agent from the feedstock for use in an alkylation reaction, especially of aromatics such as toluene and benzene. Preferred alkylating agents include methanol and mixtures of carbon monoxide and hydrogen, for methylation of toluene and/or benzene. The methylation proceeds over an aluminosilicate catalyst and preferably yields para-xylene with 75% or greater selectivity.