Abstract:
A process is provided for the disproportionation of a toluene feedstock over a metal promoted mordenite catalyst. The catalyst may contain between 1.0-1.5 weight percent nickel. The toluene feedstock is supplied to the reaction zone and into contact with the catalyst. The reaction zone is operated under disproportionation conditions. During disproportionation, heavy aromatic reformates, in concentration of at least 4 weight percent, are introduced into the reaction zone. Disproportionation product containing benzene and xylene is continuously withdrawn. The addition of the heavy aromatic reformate does not adversely affect toluene conversion rates, product selectivity to benzene, catalyst activity or catalyst life. Moreover, production of xylenes increase at the expense of production of heavies.
Abstract:
A process for the transalkylation of polyalkylated aromatic compounds over a high porosity zeolite-Y molecular sieve having a surface area of no more than 500 m2/g. A feedstock comprising a polyalkylated aromatic component, including polyalkylbenzenes in which the predominant alkyl substituents contain from 2 to 4 carbon atoms, is supplied to a transalkylation reaction zone containing the high porosity zeolite-Y catalyst. Benzene is also supplied to the transalkylation zone, and the reaction zone is operated under temperature and pressure conditions to maintain the polyalkylated aromatic component in the liquid phase and which are effective to cause disproportionation of the polyalkylated aromatic component to arrive a disproportionation product having a reduced polyalkylbenzene content and an enhanced monoalkylbenzene content. An alkylation reaction zone is provided which contains a molecular sieve aromatic alkylation catalyst having an average pore size which is less than the average pore size of the average pore size of the high porosity zeolite-Y. A feedstock comprising benzene in a C2-C4 alkylating agent is supplied to the alkylation reaction zone which is operated under conditions to produce alkylation of the benzene by the alkylating agent in the presence of the molecular sieve alkylation catalyst. The alkylation product from the alkylation reaction zone is supplied to an intermediate recovery zone for the separation and recovery of a monoalkylbenzene, e.g. ethylbenzene, from the alkylation product; together with the recovery of a polyalkylated aromatic component employing a dialkylbenzene, e.g. diethylbenzene. The polyalkylated aromatic component is employed in at least a portion of the feedstream supplied to the transalkylation reactor.
Abstract:
A process for the production of ethylbenzene by the gas phase alkylation of benzene over a molecular sieve aromatic alkylation catalyst followed by liquid phase alkylation of the product of the gas phase alkylation. A feedstock containing benzene and ethylene is supplied to a first alkylation reaction zone containing a molecular sieve aromatic alkylation catalyst. The reaction zone is operated at temperature and pressure conditions to cause gas phase ethylation of the benzene with the production of an alkylation product comprising a mixture of ethylbenzene and polyalkylated aromatic components including diethylbenzene. The output from the first alkylation reaction zone is supplied, at least in part, to a second alkylation zone which is operated in the liquid phase or in the supercritical region followed by supply to an intermediate recovery zone for the separation and recovery of ethylbenzene and a polyalkylated aromatic compound component including diethylbenzene.
Abstract:
A process for the production of ethylbenzene by the alkylation of benzene over a molecular sieve aromatic alkylation catalyst followed by transalkylation of polyalkylated aromatic components and then liquid phase alkylation. A feedstock containing benzene and ethylene is supplied to a first alkylation reaction zone containing a molecular sieve aromatic alkylation catalyst. The reaction zone is operated at temperature and pressure conditions to cause gas phase ethylation of the benzene with the production of an alkylation product comprising a mixture of ethylbenzene and polyalkylated aromatic components including diethylbenzene with xylene present in only small amounts. The output from the alkylation reaction zone is supplied to an intermediate recovery zone for the separation and recovery of ethybenzene, a polyalkylated aromatic compound component including diethylbenzene. At least a portion of the polyalkylated component is supplied along with benzene to a transalkylation reaction zone operated in the liquid phase. Disproportionation product from the transalkylaton reaction zone is supplied to a second alkylation zone containing a molecular sieve aromatic alkylation catalyst. Ethylene is also supplied to the second alkylation zone which is operated under temperature and pressure conditions to cause liquid phase ethylation of the benzene. The alkylation product from the second alkylation zone is supplied to the aforementioned intermediate recovery zone.
Abstract:
Process for the production of ethylbenzene by alkylation over a silicalite alkylation catalyst with the subsequent transalkylation of diethylbenzene with the alkylation catalyst and conditions selected to retard xylene production and also heavies production. A feedstock containing benzene and ethylene is applied to a multi-stage alkylation reaction zone having a plurality of series-connected catalyst beds containing a pentasil molecular sieve alkylation catalyst which is silicalite of a predominantly monoclinic symmetry having a silica/alumina ratio of at least 275. The feedstock is supplied to the alkylation reaction zone to cause gas-phase ethylation of benzene at a flow rate to provide a space velocity of benzene over the catalyst to produce a xylene concentration in the product of about 600 ppm or less based upon the ethylbenzene content. Periodically the space velocity may be increased to a value which is greater than the space velocity associated with a minimum concentration of diethylbenzene in the alkylation product such that diethylbenzene production is enhanced while minimizing any attendant transalkylation reactions within the alkylation reaction zone. This is accompanied by a relatively low xylene content in the product, specifically no more than 600 ppm based upon the ethylbenzene in the product. The output from the alkylation reactor is applied to an intermediate recovery zone for the separation and recovery of ethylbenzene with the recovery of a polyalkylated aromatic component which is supplied along with benzene to a transalkylation reaction zone where the polyalkylated aromatic fraction is subject to disproportionation to provide a reduced diethylbenzene content and an enhanced ethylbenzene content.
Abstract:
A method of producing an alkylaromatic by the alkylation of an aromatic with an alkylating agent, such as producing ethylbenzene by an alkylation reaction of benzene, is disclosed. The method includes using an H-beta catalyst to minimize process upsets due to alkylation catalyst deactivation and the resulting catalyst regeneration or replacement. The H-beta catalyst can be used in a preliminary alkylation reactor that is located upstream of the primary alkylation reactor. The H-beta catalyst used in a preliminary alkylation reactor can reduce the deactivation of the catalyst in the primary alkylation reactor.
Abstract:
A process for making styrene is disclosed that includes providing toluene, a co-feed, and a C1 source to a reactor containing a catalyst, reacting toluene with the C1 source in the presence of the catalyst and the co-feed to form a product stream containing ethylbenzene and styrene. The co-feed can be selected from the group of water, carbon monoxide, hydrogen, and combinations thereof.
Abstract:
Methods of forming ethylbenzene are described herein. In one embodiment, the method includes contacting dilute ethylene with benzene in the presence of an alkylation catalyst to form ethylbenzene, wherein such contact occurs in a reaction zone containing a gaseous phase and recovering ethylbenzene from the reaction zone.
Abstract:
A process for making ethylbenzene and/or styrene by reacting toluene with methane is disclosed. In one embodiment the process can include reacting toluene with methane to form a product stream comprising ethylbenzene and further processing the ethylbenzene to form styrene in an existing styrene production facility.
Abstract:
A process for the coupling of hydrocarbons and utilizing the heat energy produced by the reaction is disclosed. In one embodiment the process can include reacting methane with oxygen to form a product stream containing ethane and further processing the ethane to ethylene in an existing ethylene production facility while using the heat energy produced by the reaction within the facility.