Use of Swing Preliminary Alkylation Reactors

Abstract

Alkylation systems and processes are described herein. The alkylation system generally includes a preliminary alkylation system containing a preliminary alkylation catalyst therein and adapted to contact an aromatic compound and an alkylating agent with the preliminary alkylation catalyst so as to alkylate the aromatic compound and form a preliminary output stream, wherein the preliminary alkylation system includes a first preliminary alkylation reactor and a second preliminary alkylation reactor connected in parallel to the first preliminary alkylation reactor and a primary alkylation system adapted to receive the preliminary output stream and contact the preliminary output stream and the alkylating agent with a primary alkylation catalyst disposed therein so as to form a primary output stream.

What is claimed: 
     
         1 - 7 . (canceled) 
     
     
         8 . An alkylation process comprising:
 providing an aromatic compound and an alkylating agent;   contacting the aromatic compound and the alkylating agent with a preliminary alkylation catalyst within a preliminary alkylation system so as to alkylate the aromatic compound and form a preliminary output stream, wherein the preliminary alkylation system comprises a first preliminary alkylation reactor and a second preliminary alkylation reactor connected in parallel to the first preliminary alkylation reactor, and wherein the preliminary alkylation system is operated at a temperature of from about 160° C. to about 270 ° C.;   passing the preliminary output stream to a primary alkylation system; and   contacting the preliminary output stream and the alkylating agent with a primary alkylation catalyst disposed therein so as to form a primary output stream.   
     
     
         9 . The process of  claim 8 , wherein the preliminary alkylation catalyst comprises a cerium promoted zeolite beta. 
     
     
         10 . The process of  claim 8 , wherein flow of the aromatic compound and the alkylating agent is terminated to one of the preliminary alkylation reactors for maintenance thereof, while flow of the aromatic compound and the alkylating agent continues in the other preliminary alkylation reactor. 
     
     
         11 . The process of  claim 10 , wherein the maintenance includes catalyst regeneration. 
     
     
         12 . The process of  claim 8 , wherein the preliminary alkylation catalyst has a catalyst life of at least 3 weeks prior to regeneration. 
     
     
         13 . The process of  claim 8 , wherein the preliminary alkylation output comprises less than 100 ppb alkylation catalyst poisons. 
     
     
         14 . The process of  claim 13 , wherein the process is absent a guard bed prior to the preliminary alkylation system. 
     
     
         15 . The process of  claim 10 , wherein the regeneration occurs within the preliminary alkylation system. 
     
     
         16 . The process of  claim 8 , wherein the preliminary alkylation catalyst in the preliminary alkylation system has a silica to alumina molar ratio ranging from 10 to 200. 
     
     
         17 . The process of  claim 16 , wherein the silica to alumina molar ratio of the preliminary alkylation catalyst is less than 100. 
     
     
         18 . The process of  claim 8 , wherein the preliminary alkylation system is operated at a pressure of from about 97 psi to about 1200 psi. 
     
     
         19 . The process of  claim 8 , wherein the preliminary alkylation catalyst comprises a cerium promoted zeolite Y catalyst. 
     
     
         20 . The process of  claim 8 , wherein the preliminary alkylation catalyst comprises a zeolite beta catalyst. 
     
     
         21 . The process of  claim 8 , wherein the primary alkylation catalyst has a silica to alumina molar ratio ranging from 10 to 200. 
     
     
         22 . An alkylation process comprising:
 contacting an aromatic compound and an alkylating agent with a preliminary alkylation catalyst within a preliminary alkylation system under liquid phase conditions at a temperature ranging from about 160° C. to about 270 ° C. and a pressure ranging from about 97 psi to about 1200 psi so as to alkylate the aromatic compound and form a preliminary output stream comprising less than 100 ppb alkylation catalyst poisons, wherein the preliminary alkylation system comprises a first preliminary alkylation reactor and a second preliminary alkylation reactor connected in parallel to the first preliminary alkylation reactor, wherein each of the first preliminary alkylation reactor and the second preliminary alkylation reactor contain the preliminary alkylation catalyst, wherein the preliminary alkylation catalyst has an silica to alumina molar ratio ranging from 10 to 200, and wherein the process is absent a guard bed prior to the preliminary alkylation system;   passing the preliminary output stream to a primary alkylation system; and   contacting the preliminary output stream and the alkylating agent with a primary alkylation catalyst disposed therein so as to form a primary output stream, wherein the primary alkylation catalyst has a silica to alumina molar ratio ranging from 10 to 200.   
     
     
         23 . The process of  claim 22 , wherein the preliminary alkylation output comprises less than 30 ppb alkylation catalyst poisons. 
     
     
         24 . The process of  claim 22 , wherein contacting the aromatic compound and the alkylating agent with the preliminary alkylation catalyst within the preliminary alkylation system reduces the level of poisons present in the alkylating agent by at least 10%. 
     
     
         25 . The process of  claim 22 , wherein the aromatic compound comprises at least 95 weight percent benzene. 
     
     
         26 . The process of  claim 22 , wherein the preliminary alkylation catalyst has an silica to alumina molar ratio ranging from 20 to 50,