Abstract: The invention is directed to a process to produce paraxylene and orthoxylene, including reducing the amount of isomerate recycle from vapor phase xylenes isomerization by providing a parallel configuration of vapor phase and liquid phase isomerization units.

Abstract: A process for the purification of aromatic feedstream to produce paraxylene is disclosed, including the separation of a C8+ aromatic feedstream into a steam comprising C8 aromatic species and a stream comprising C9+ aromatic species. After separation of PX from the C8 aromatic stream, a PX-depleted stream is separated and processed in a liquid phase isomerization unit and a vapor phase isomerization unit in parallel.

Abstract: The invention concerns a process for the production of paraxylene and an apparatus suitable for said process. The process separates the overhead from a xylenes re-run into a xylene-rich stream and a xylene-lean stream. The xylene-lean stream is isomerized under conditions such that the xylenes are in the liquid phase.

Abstract: The invention concerns a xylenes isomerization process for the production of equilibrium or near-equilibrium xylenes. The process utilizes a catalyst comprising HZSM-5 or MCM-49 and process conditions including a temperature of less than 295° C. and a pressure sufficient to maintain the xylenes in liquid phase. In embodiments, the process can be operated in a continuous mode with ppm levels of dissolved H2 in the feed and in other embodiments in a cyclic mode without the H2 in feed but with periodic regenerations using a feed having low ppm levels of H2.

Abstract: In a process for the production of para-xylene, methanol is preheated to a first temperature, an aromatic feedstock comprising toluene and/or benzene is preheated to a second temperature and the preheated methanol and aromatic feedstocks are fed to a reactor at a first methanol to aromatic feedstock molar ratio. The preheated aromatic feedstock is contacted with the preheated methanol under alkylation conditions in the reactor in the presence of a catalyst so that the methanol reacts with the aromatic feedstock to produce an effluent comprising para-xylene. During the reaction, a temperature is measured within the reactor and is compared with a predetermined optimal temperature. The methanol to aromatic feedstock molar ratio is then adjusted in a manner to reduce any difference between the measured and predetermined optimal temperatures in the reactor.

Abstract: The management of hydrogen in hydrogen-containing streams associated with petrochemical process units wherein the hydrogen-containing stream is subjected rapid cycle pressure swing adsorption to increase the concentration of hydrogen therein.

Abstract: This invention relates to a process of producing an upgraded product stream from steam cracker tar feedstream suitable for use in refinery or chemical plant processes or for utilization in fuel oil sales or blending. This process utilizes an ultrafiltration process for separating the steam cracker tar constituents resulting in a high recovery, low-energy process with improved separation and product properties.

Abstract: A process for producing a PX-rich product, the process comprising: (a) providing a PX-depleted stream; (b) isomerizing at least a portion of the PX-depleted stream to produce an isomerized stream having a PX concentration greater than the PX-depleted stream and a benzene concentration of less than 1,000 ppm and a C9+ hydrocarbons concentration of less than 5,000 ppm; and (c) separating the isomerized stream by selective adsorption.

Abstract: An oxygenate conversion catalyst useful in the conversion of oxygenates such as methanol to olefinic products may be improved by the use of a catalyst combination based on a molecular sieve in combination with a co-catalyst comprising a mixed metal oxide composition which has oxidation/reduction functionality under the conditions of the conversion. This metal oxide co-catalyst component will comprise a mixed oxide of one or more, preferably at least two, transition metals, usually of Series 4, 5 or 6 of the Periodic Table, with the metals of Series 4 being preferred, as an essential component of the mixed oxide composition. The preferred transition metals are those of Groups 5, especially titanium and vanadium, Group 6, especially chromium or molybdenum, Group 7, especially manganese and Group 8, especially cobalt or nickel. Other metal oxides may also be present.

Abstract: In a process for producing a para-xylene enriched product from a gaseous mixture comprising at least para-xylene, meta-xylene and ortho-xylene, the gaseous mixture is contacted with an adsorbent capable of selectively adsorbing para-xylene and comprising a crystalline molecular sieve having an average crystal size between about 0.5 micron and about 20 microns. The contacting is conducted at a temperature and pressure such that at least part of the para-xylene in the mixture is adsorbed by the adsorbent to produce a para-xylene-depleted effluent stream. The para-xylene is then desorbed from said adsorbent and collected to form a para-xylene enriched stream. The adsorption and desorption steps are repeated for a plurality of cycles, such that the time between successive contacting steps is no more than 10 seconds.

Abstract: A process for producing a PX-rich product comprises (a) separating a feedstock containing C8 hydrocarbons to produce a C8 hydrocarbons rich stream; (b) separating at least a first portion of the C8 hydrocarbons rich stream to produce a first PX-rich stream and a first PX-depleted stream; (c) isomerizing at least a portion of the first PX-depleted stream to produce a first isomerized stream having a higher PX concentration than the first PX-depleted stream; (d) separating a second portion of the C8 hydrocarbons rich stream and/or at least a portion of the first isomerized stream to produce a second PX-rich stream and a second PX-depleted stream; (e) isomerizing at least a portion of the second PX-depleted stream to produce a second isomerized stream having a higher PX concentration than the second PX-depleted stream; (f) recovering at least a portion of at least one of the first and second PX-rich streams as PX-rich product; and (g) supplying at least a portion of at least one of the first isomerized stream, t

Abstract: The use of rapid cycle pressure swing adsorption having a cycle time of less than 30 s for increasing the hydrogen concentration in hydrogen-containing steams, from a hydrogen source, such as a stream reforming unit.

Abstract: This invention relates to a process of producing an upgraded product stream from steam cracker tar feedstream suitable for use in refinery or chemical plant processes or for utilization in fuel oil sales or blending. This process utilizes an ultrafiltration process for separating the steam cracker tar constituents resulting in a high recovery, low-energy process with improved separation and product properties.

Abstract: The management of hydrogen in hydrogen-containing streams associated with petrochemical process units wherein the hydrogen-containing stream is subjected rapid cycle pressure swing adsorption to increase the concentration of hydrogen therein.

Abstract: A process for producing a PX-rich product comprises (a) separating a feedstock containing C8 hydrocarbons to produce a C8 hydrocarbons rich stream; (b) separating at least a first portion of the C8 hydrocarbons rich stream to produce a first PX-rich stream and a first PX-depleted stream; (c) isomerizing at least a portion of the first PX-depleted stream to produce a first isomerized stream having a higher PX concentration than the first PX-depleted stream; (d) separating a second portion of the C8 hydrocarbons rich stream and/or at least a portion of the first isomerized stream to produce a second PX-rich stream and a second PX-depleted stream; (e) isomerizing at least a portion of the second PX-depleted stream to produce a second isomerized stream having a higher PX concentration than the second PX-depleted stream; (f) recovering at least a portion of at least one of the first and second PX-rich streams as PX-rich product; and (g) supplying at least a portion of at least one of the first isomerized stream, t

Abstract: A process for producing a PX-rich product comprises (a) separating a feedstock containing C8 hydrocarbons to produce a C8 hydrocarbons rich stream; (b) separating at least a first portion of the C8 hydrocarbons rich stream to produce a first PX-rich stream and a first PX-depleted stream; (c) isomerizing at least a portion of the first PX-depleted stream to produce a first isomerized stream having a higher PX concentration than the first PX-depleted stream; (d) separating a second portion of the C8 hydrocarbons rich stream and/or at least a portion of the first isomerized stream to produce a second PX-rich stream and a second PX-depleted stream; (e) isomerizing at least a portion of the second PX-depleted stream to produce a second isomerized stream having a higher PX concentration than the second PX-depleted stream; (f) recovering at least a portion of at least one of the first and second PX-rich streams as PX-rich product; and (g) supplying at least a portion of at least one of the first isomerized stream, t

Abstract: In a process for producing a para-xylene enriched product from a gaseous mixture comprising at least para-xylene, meta-xylene and ortho-xylene, the gaseous mixture is contacted with an adsorbent capable of selectively adsorbing para-xylene and comprising a crystalline molecular sieve having an average crystal size between about 0.5 micron and about 20 microns. The contacting is conducted at a temperature and pressure such that at least part of the para-xylene in the mixture is adsorbed by the adsorbent to produce a para-xylene-depleted effluent stream. The para-xylene is then desorbed from said adsorbent and collected to form a para-xylene enriched stream. The adsorption and desorption steps are repeated for a plurality of cycles, such that the time between successive contacting steps is no more than 10 seconds.

Abstract: This invention is to a process for removing dimethyl ether from an olefin stream. The process includes contacting the olefin stream with a molecular sieve that has improved capacity to adsorb the dimethyl ether from the olefin stream. The molecular sieve used to remove the dimethyl ether has low or no activity in converting the olefin in the olefin stream to other products.

Abstract: A process for producing a PX-rich product comprises (a) separating a feedstock containing C8 hydrocarbons to produce a C8 hydrocarbons rich stream; (b) separating at least a first portion of the C8 hydrocarbons rich stream to produce a first PX-rich stream and a first PX-depleted stream; (c) isomerizing at least a portion of the first PX-depleted stream to produce a first isomerized stream having a higher PX concentration than the first PX-depleted stream; (d) separating a second portion of the C8 hydrocarbons rich stream and/or at least a portion of the first isomerized stream to produce a second PX-rich stream and a second PX-depleted stream; (e) isomerizing at least a portion of the second PX-depleted stream to produce a second isomerized stream having a higher PX concentration than the second PX-depleted stream; (f) recovering at least a portion of at least one of the first and second PX-rich streams as PX-rich product; and (g) supplying at least a portion of at least one of the first isomerized stream, t

Abstract: A process and a system for increasing para-xylene production from a C8 aromatic feedstream by coupling at least one xylene isomerization reactor with at least one pressure swing adsorption unit or temperature swing absorption unit to produce a product having a super-equilibrium para-xylene concentration. This product is then subjected to para-xylene separation and purification.