Abstract: In a process for producing styrene, benzene is alkylated with ethylene to produce ethylbenzene and at least some of the ethylbenzene is dehydrogenated to produce styrene, together with benzene and toluene as by-products. At least part of the benzene by-product is passed through a bed of an adsorbent comprising at least one of an acidic clay, alumina, an acidic ion exchange resin and an acidic molecular sieve to remove basic nitrogenous impurities therefrom and produce a purified benzene by-product, which is then recycled to the alkylation step.

Abstract: Disclosed are processes for purifying feed streams containing hydrogen sulfide and sulfur-containing impurities by removing sulfur-containing impurities, such as elemental sulfur and polysulfanes, using solid catalytic sorbents. Also disclosed are processes for producing hydrogen sulfide.

Abstract: In a process for alkylating an aromatic hydrocarbon feedstock with an olefin feedstock, at least one of the aromatic hydrocarbon and olefin feedstocks is passed through a pretreatment unit containing an adsorbent such that the adsorbent removes impurities contained by the feedstock. Passage of the at least one feedstock through the pretreatment unit is then terminated and a heated inert gas is passed through the pretreatment unit such that the inert gas desorbs impurities from the adsorbent to produce an inert gas effluent stream containing the desorbed impurities. A condensable fluid is added to at least part of the inert gas effluent stream such that at least a portion of the impurities contained therein condense with said fluid to leave a purified inert gas stream, which is recycled to the pretreatment unit.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer shiny having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A system and method for a first reactor to produce a transfer slurry having a first polyolefin polymerized in the first reactor, a heat-removal zone to remove heat from the transfer slurry, and a second reactor to receive the transfer slurry cooled by the heat-removal zone, the second reactor to produce a product slurry having a product polyolefin which includes the first polyolefin and a second polyolefin polymerized in the second reactor.

Abstract: Disclosed is a process for the production of alkylated aromatics by contacting a feed stream comprising an alkylatable aromatic, an alkylating agent and trace amounts of water and impurities in the presence of a first catalyst and an alkylation catalyst wherein such water and impurities are removed in order to improve the cycle length of such alkylation catalysts. Water and at least a portion of impurities are removed in a dehydration zone. A reaction zone having a first catalyst which, in some embodiments is a large pore molecular sieve, acts to remove another portion of impurities, such as nitrogenous and other species. An alkylation zone having an alkylation catalyst which, in some embodiments is a medium pore molecular sieve or a MCM-22 family material, acts to remove additional impurities, and to alkylate the alkylatable aromatic compound.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: A technique for polymerizing ethylene on catalyst in a first polymerization reactor and in a second polymerization reactor to form polyethylene particles, and controlling particle size of the polyethylene particles.

Abstract: A system and method for discharging a transfer slurry from a first polymerization reactor through a transfer line to a second polymerization reactor, the transfer slurry including at least diluent and a first polyethylene. A product slurry is discharged from the second polymerization reactor, the product slurry including at least diluent, the first polyethylene, and a second polyethylene. The velocity, pressure drop, or pressure loss due to friction in the transfer line is determined, and a process variable adjusted in response to the velocity, pressure drop, or pressure loss not satisfying a specified value.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A polyolefin production system including: a first reactor configured to produce a first discharge slurry having a first polyolefin; a second reactor configured to produce a second discharge slurry having a second polyolefin; and a post-reactor treatment zone having at least a separation vessel configured to receive the second discharge slurry or both the first discharge slurry and the second discharge slurry.

Abstract: Disclosed is a process for the production of alkylated aromatics by contacting a feed stream comprising an alkylatable aromatic, an alkylating agent and trace amounts of water and impurities in the presence of a first catalyst and an alkylation catalyst wherein such water and impurities are removed in order to improve the cycle length of such alkylation catalysts. Water and at least a portion of impurities are removed in a dehydration zone. A reaction zone having a first catalyst which, in some embodiments is a large pore molecular sieve, acts to remove another portion of impurities, such as nitrogenous and other species. An alkylation zone having an alkylation catalyst which, in some embodiments is a medium pore molecular sieve or a MCM-22 family material, acts to remove additional impurities, and to alkylate the alkylatable aromatic compound.

Abstract: Disclosed is a process for the production of alkylated aromatics by contacting a feed stream comprising an alkylatable aromatic, an alkylating agent and trace amounts of water and impurities in the presence of first and second alkylation catalysts wherein the water and impurities are removed in order to improve the cycle length of such alkylation catalysts. Water and a portion of impurities are removed in a dehydration zone. A first alkylation zone having a first alkylation catalyst which, in some embodiments is a large pore molecular sieve, acts to remove a larger portion of impurities, such as nitrogenous and other species, and to alkylate a smaller portion of the alkylatable aromatic compound. A second alkylation zone, which in some embodiments is a medium pore molecular sieve, acts to remove a smaller portion of impurities, and to alkylate a larger portion of the alkylatable aromatic compound.

Abstract: The present invention provides an improved process for the catalytic conversion of a feedstock comprising an alkylatable aromatic compound and an alkylating agent to form a conversion product comprising the desired alkylaromatic compound by contacting said feedstock in at least partial liquid phase under catalytic conversion conditions with a catalyst composition comprising a porous crystalline material having a structure type of FAU, BEA* or MWW, or a mixture thereof, wherein the porous crystalline material has a Relative Activity measured at 220° C. as an RA220 of at least 7.5 or measured at 180° C. as RA180 of at least 2.5, allowing operation at lower reaction pressures, e.g., a reaction pressure of about 450 psig (3102 kPa) or less, and lower alkylating agent feed supply pressure of 450 psig (3102 kPa) or less.

Abstract: Disclosed are ethylbenzene processes in which a series-arranged or combined vapor phase alkylation/transalkylation reaction zone is retrofitted to have a vapor phase alkylation reactor and a liquid phase transalkylation reactor, and in which a parallel-arranged vapor phase alkylation reactor and vapor phase transalkylation reactor is retrofitted to have a vapor phase alkylation reactor and liquid phase transalkylation reactor, wherein the xylenes content of the ethylbenzene product is less than 700 wppm.

Abstract: Disclosed is a process for the production of alkylated aromatics by contacting a feed stream comprising an alkylatable aromatic, an alkylating agent and trace amounts of water and impurities in the presence of first and second alkylation catalysts wherein the water and impurities are removed in order to improve the cycle length of such alkylation catalysts. Water and a portion of impurities are removed in a dehydration zone. A first alkylation zone having a first alkylation catalyst which, in some embodiments is a large pore molecular sieve, acts to remove a larger portion of impurities, such as nitrogenous and other species, and to alkylate a smaller portion of the alkylatable aromatic compound. A second alkylation zone, which in some embodiments is a medium pore molecular sieve, acts to remove a smaller portion of impurities, and to alkylate a larger portion of the alkylatable aromatic compound.