Abstract:
A process is disclosed for making styrene by converting methanol to formaldehyde in a reactor then reacting the formaldehyde with toluene to form styrene in a separate reactor.
Abstract:
A method of reducing the ethylbenzene content in a stream containing xylene is disclosed. The method includes the reaction of ethylbenzene, such as a disproportionation or transalkylation reaction, to produce benzene and other hydrocarbon compound and can include the separation of at least a portion of the resulting benzene and other hydrocarbon compounds to produce a xylene stream having reduced ethylbenzene content.
Abstract:
A process for making ethylbenzene and/or styrene by reacting toluene with methane in one or more microreactors is disclosed. In one embodiment a method of revamping an existing styrene production facility by adding one or more microreactors capable of reacting toluene with methane to produce a product stream comprising ethylbenzene and/or styrene is disclosed.
Abstract:
Methods and processes for reducing alkylation catalyst poisoning are described herein. Such methods generally include providing a dehydrogenation system including a dehydrogenation reactor and a separation system, wherein the separation system includes a first column and a second column, introducing an alkyl aromatic hydrocarbon into the dehydrogenation reactor, contacting the alkyl aromatic hydrocarbon with a dehydrogenation catalyst disposed within the dehydrogenation reactor to form a dehydrogenation output stream comprising a vinyl aromatic hydrocarbon, passing at least a portion of the dehydrogenation output stream to first column, recovering a first overhead fraction including benzene and a first bottoms fraction from the first column, passing at least a portion of the benzene from the first column to an alkylation system including an alkylation catalyst, passing the first bottoms fraction from the first column to the second column, recovering a second overhead fraction and a second bottoms fraction from the second column, withdrawing offtest from effluent streams selected from the dehydrogenation output stream, the first bottoms fraction, the second bottoms fraction and combinations thereof to form withdrawn offtest and introducing the withdrawn offtest into the separation system downstream from the first column.
Abstract:
A process for the disproportionation of a toluene containing feedstock employing a nickel modified mordenite catalyst comprising particulate mordenite having nickel dispersed throughout the catalyst particles to provide surface nickel and interior nickel within the mordenite crystal structure. The catalyst is pretreated to selectively deactivate the surface nickel to provide a surface nickel content of reduced catalytic activity. The interior nickel thus has a higher catalytic activity than the surface nickel. The feedstock is supplied to a reaction zone containing the catalyst to cause disproportionation of toluene in the feedstock to produce a mixture of benzene and xylene. The non-aromatic content of the product is less than the non-aromatic content of a corresponding disproportionation product which would be produced by the disproportionation of the feedstream in the presence of a corresponding nickel mordenite catalyst which has not been pretreated.
Abstract:
The present invention provides a process for the preparation of a catalyst having a high surface area and pore volume. The process includes freeze drying an intermediary of the catalyst. The present invention further includes a catalyst prepared by a process that includes the freeze drying step. The present invention also includes a catalyst having a high acidity, as indicated by having an ammonium desorption peak at greater than about 500° C. The prevent invention further includes a method of manufacturing isomerized organic compounds using the catalyst.
Abstract:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase over a molecular sieve aromatic alkylation catalyst comprising cerium-promoted zeolite beta. An aromatic feedstock having a benzene content of at least 90 wt. % is supplied into a reaction zone and into contact with the cerium-promoted zeolite beta having a silica/alumina mole ratio within the range of 50-150 and a cerium-aluminum ratio of 0.5-1.5. Ethylene is supplied to the alkylation reaction zone in an amount to provide a benzene/ethylene mole ratio of 1-15. The reaction zone is operated at temperature and pressure conditions in which benzene is in the super critical phase to cause ethylation of the benzene in the presence of the cerium zeolite beta alkylation catalyst. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated by-products of no more than 60 wt. % of the ethylbenzene. The critical phase alkylation reaction may be followed by the transalkylation of a polyalkylated aromatic component.
Abstract:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase in a reaction zone containing a molecular sieve aromatic alkylation catalyst comprising cerium-promoted zeolite beta. A polyethylbenzene is supplied into the reaction zone and into contact with the cerium-promoted zeolite beta having a silica/alumina mole ratio within the range of 20-500. The reaction zone is operated at temperature and pressure conditions in which benzene is in the supercritical phase to cause ethylation of the benzene and the transalkylation of polyethylbenzene and benzene in the presence of the zeolite beta catalyst. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated byproducts of no more than 60 wt. % of the ethylbenzene. The alkylation reaction zone is operated under conditions providing a composite byproduct yield of propyl benzene and butyl benzene relative to ethylbenzene, which is no more than one half of the corresponding yield byproduct for zeolite beta promoted with lanthanum. The production of ethylbenzene in the critical phase alkylation reaction zone is attended by recycle of a polyalkylated aromatic component of the reaction product back to the reaction zone.
Abstract:
A method for preparing a homogeneous blend of asphalt and ground tire rubber. An asphalt base material is heated to a temperature sufficient to permit the stirring of the asphalt base material within a mixing vessel. A particulate crumb rubber component having a designated average particle size is added to the asphalt base material. The crumb rubber material can be partially devulcanized or partially depolymerized and may be accompanied by the incorporation of another rubber component, such as a ground styrene butadiene rubber. Zinc oxide is added to the asphalt base material. The mixture incorporating the zinc oxide is stirred for a period sufficient to provide for substantial solubilization of the crumb rubber within the asphalt base material to provide a blend which has a higher homogeneity than a corresponding blend of the same asphalt and particulate rubber components which is heated and stirred under the identical conditions, but without the addition of the zinc oxide.
Abstract:
A process and system for the vapor phase alkylation of an aromatic substrate in a multi-stage alkylation reaction zone having a plurality of series-connected catalyst beds spaced from one another to provide mixing zones between adjacent catalyst beds. A feedstock containing an aromatic substrate and a C2–C4 alkylating agent is supplied to an inlet side of the reaction zone. The reaction zone is operated at conditions in which the aromatic substrate is in the gas phase and causing vapor phase alkylation of the aromatic substrate as the aromatic substrate and the alkylating agent flow through the reaction zone and pass from one catalyst bed to the next. A quench fluid comprising one or both of the aromatic substrate and the alkylating agent is supplied into the interior of the mixing zone through a plurality of flow paths in which one portion of the flow paths is directed upwardly within the mixing zone and another portion downwardly within the mixing zone. Alkylated product is then recovered from the downstream side of the reaction zone. The quench fluid is supplied to the mixing zone through a plurality of dispersion channels which are spaced laterally from one another and extend transversely across the mixing chamber. At least some of the dispersion channels dispense the quench fluid alternately, upwardly and downwardly within the mixing zone.