摘要:
A method for the separation of hydrocarbon compounds utilizing a dividing wall distillation column is described. The dividing wall distillation column enables one or more side draw stream to be removed from the dividing wall distillation column in addition to an overhead stream and a bottoms stream.
摘要:
A method for stabilizing pyrolysis gasoline in storage involves adding an effective amount of a quinone methide compound to the pyrolysis gasoline. The quinone methide does not require oxygen for activity. Embodiments of the quinone methide do not contain nitrogen and will have a reduced tendency for ammonia production.
摘要:
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.
摘要:
In methods of preparing asphalt and elastomeric polymer compositions such as polymer modified asphalt (PMA), it has been discovered that the compatibility can be improved by adding excess amounts of certain organic and inorganic metal salts beyond the proportions normally used. Suitable metal salts may be metal oxides that include, but are not necessarily limited to, zinc oxide, calcium oxide, and the like. The method of the invention also permits asphalt modified with other polymers such as ground tire rubber (GTR) to have improved compatibility. Additionally, the use of excess amounts of these metal salts helps control gel formation.
摘要:
A metal-modified alkylation catalyst including a metal/zeolite is provided where the metal is one or two selected from the group consisting of yttrium and a rare earth of the lanthanide series other than cerium. Where two metals are used, one may be Ce or La. The metal-promoted zeolite is useful as a molecular sieve aromatic alkylation catalyst for the production of ethylbenzene by the ethylation of benzene in the liquid phase or critical phase. An alkylation product is produced containing ethylbenzene as a primary product with the attendant production of heavier alkylated by-products of no more than 10-60 wt % of the ethyl benzene.
摘要:
Dehydrogenation processes and systems are described herein. In one embodiment, the process generally includes providing an alkyl aromatic hydrocarbon, providing a reaction zone including an oxidative dehydrogenation catalyst, introducing the alkyl aromatic hydrocarbon into the reaction zone, contacting the alkyl aromatic hydrocarbon with the oxidative dehydrogenation catalyst to form a vinyl aromatic hydrocarbon and withdrawing the vinyl aromatic hydrocarbon from the reaction zone. The process generally utilizes a catalyst to oil ratio that is at least 10:1.
摘要:
A process for the production of ethylbenzene by the ethylation of benzene in the critical phase over a molecular sieve aromatic alkylation catalyst. An aromatic feedstock having a benzene content of at least 90 wt. % is supplied into a reaction zone into contact with a zeolite beta alkylation catalyst having a silica/alumina ratio within the range of 20-500, specifically 50-150. The alkylation catalyst is a zeolite beta specifically a lanthanum-modified zeolite beta. Ethylene is supplied to the reaction zone to provide a benzene/ethylene mole ratio of 1-15. The reaction zone is operated under conditions in which benzene is in the supercritical phase to produce an alkylation product containing ethylbenzene as a primary product with heavier alkylated by-products of no more than 60 wt. % of the ethylbenzene. The alkylation product is recovered from the reaction zone and supplied to a separation and recovery zone to separate ethylbenzene from a polyalkylated component including diethylbenzene. At least a portion of the polyalkylated component is supplied to a transalkylation reaction zone containing a molecular sieve transalkylation catalyst. The transalkylation reaction zone contains a zeolite Y catalyst and is operated under liquid phase conditions.