Abstract:
Alkylation systems and methods of minimizing alkylation catalyst regeneration are described herein. The alkylation systems generally include a preliminary alkylation system adapted to receive an input stream including an alkyl aromatic hydrocarbon and contact the input stream with a preliminary alkylation catalyst disposed therein to form a first output stream. The preliminary alkylation catalyst generally includes a zeolite catalyst having a SiO2/Al2O3 ratio of less than about 25. The alkylation systems further include a first alkylation system adapted to receive the first output stream and contact the first output stream with a first alkylation catalyst disposed therein and an alkylating agent to form a second output stream.
Abstract translation:本文描述了使烷基化催化剂再生最小化的烷基化系统和方法。 烷基化系统通常包括适于接收包含烷基芳族烃的输入流并将输入流与设置在其中的预置烷基化催化剂接触以形成第一输出流的初步烷基化系统。 初步烷基化催化剂通常包括SiO 2 / Al 2 O 3比小于约25的沸石催化剂。烷基化系统还包括适于接收第一输出流并将第一输出流与置于其中的第一烷基化催化剂接触的第一烷基化系统 和烷基化剂以形成第二输出流。
Abstract:
Alkylation systems and methods of minimizing alkylation catalyst regeneration are discussed herein. The alkylation systems generally include a preliminary alkylation system adapted to receive an input stream including an alkyl aromatic hydrocarbon and contact the input stream with a first preliminary alkylation catalyst disposed therein to form a first output stream. The first preliminary alkylation catalyst generally includes a Y zeolite. The systems further include a first alkylation system adapted to receive the first output stream and contact the first output stream with a first alkylation catalyst disposed therein and an alkylating agent to form a second output stream.
Abstract:
Methods and systems for petrochemical feedstream purification are described herein. The methods generally include providing a petrochemical feedstock, wherein the petrochemical feedstock includes a concentration of polar impurities, contacting the petrochemical feedstock with a washing agent to remove at least a portion of the polar impurities therefrom, separating the washing agent from the petrochemical feedstock to form a purified feedstock and passing the purified feedstock to a petrochemical process. In one embodiment, the petrochemical feedstock includes benzene and the washing agent includes water.
Abstract:
Process for the catalytic dehydrogenation of a C2 or C3 alkyl aromatic in which a feedstock containing the alkyl aromatic and steam is supplied into the inlet of a tubular reactor containing a dehydrogenation catalyst. Within the reactor, the feedstock flows through at least a portion of the reactor along a spiral flow path extending longitudinally of the reactor. The resulting vinyl aromatic product is then recovered from a downstream or outlet section of the reactor. The spiral flow path through which the feedstock is passed is located at least adjacent the inlet side of the reactor and at least a portion of the spiral flow path contains a particulate dehydrogenation catalyst. The spiral flow path may extend throughout a major portion of the elongated tubular reactor and may contain a particulate dehydrogenation catalyst in a substantial portion there. The feedstock containing the alkyl aromatic and steam is supplied into a plurality of tubular reactors located within the interior of a dehydrogenation reactor vessel and is arranged in a parallel relationship in which the tubular reactors are spaced laterally from one another and from the interior wall of the reaction vessel.
Abstract:
Process for the catalytic dehydrogenation of ethylbenzene in which a feedstock containing ethylbenzene and steam is supplied into the inlet of a tubular reactor containing a dehydrogehation catalyst. Within the reactor, the feedstock flows through at least a portion of the reactor along a spiral flow path extending longitudinally of the reactor. The resulting styrene product is then recovered from a downstream or outlet section of the reactor. The spiral flow path through which the feedstock is passed is located at least adjacent the inlet side of the reactor and at least a portion of the spiral flow path contains a particulate dehydrogenation catalyst. The spiral flow path may extend throughout a major portion of the elongated tubular reactor and may contain a particulate dehydrogenation catalyst in a substantial portion there.
Abstract:
An alkylation/transalkylation process involving vapor phase alkylation of a benzene feedstock in a multi-stage alkylation zone having a plurality of series connected catalyst beds containing a pentasil aromatic alkylation catalyst, such as silicalite, coupled with intermediate separation and recirculation steps and liquid phase transalkylation over a transalkylation catalyst comprising a molecular sieve having a pore size greater than the pore size of the silicalite. The benzene containing feedstock is supplied to the multi-stage alkylation reaction zone along with a C.sub.2 -C.sub.4 alkylating agent operated under temperature and pressure conditions to maintain the benzene in the gas phase. Alkylated product is recovered from the alkylation zone and supplied to a benzene recovery zone for the separation of the benzene from the alkylation product. Benzene from the benzene recovery zone is recycled to the reaction zone. A higher boiling bottom fraction containing a mixture of monoalkylated and polyalkylated aromatic components is supplied to a secondary separation zone from which a monoalkylated aromatic component, e.g. ethylbenzene, is recovered overhead with a heavier polyalkylated aromatic recovered as a bottom fraction. The bottom fraction may be applied to a tertiary separation zone.
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.