Catalytic distillation alkylation

CD-Cumene A process for making cumene for subsequent conversion to phenol and acetone. The cumene is made by catalytic alkylation of benzene with propylene in a catalytic distillation reactor. Developed in 1995 by CDTech. 

Zhang J, Li D, Fu J, Cao G. Process and apparatus for preparation of ethylbenzene by alkylation of benzene with dilute ethylene contained in dry gas by catalytic distillation. U.S. Patent Appl. 2001018545, 2001. 

Catalytic distillation Adsorption Olefinic alkylation Extractive mass... 

Application Advanced technology to produce high-purity cumene from propylene and benzene using patented catalytic distillation (CD) technology. The CDCumene process uses a specially formulated zeolite alkylation catalyst packaged in a proprietary CD structure and another specially formulated zeolite transalkylation catalyst in loose form. 

Application To produce ethylbenzene (EB) by alkylating benzene with ethylene using a patented ethylbenzene (EB) fixed-bed, catalytic distillation technology with a zeolite catalyst. 

CDTECH Ethylbenzene Benzene, ethylene Patented fix-bed, catalytic distillation technology uses zeolite catalyst to alkylate benzene with ethylene NA NA... 

The CDTECH alkylation reactor consists of two main sections—a catalytic distillation section and a standard distillation section—as shown in Fig. 6. Benzene is fed to the top of the alkylation reactor and ethylene is fed as a vapor below the catalytic distillation section, creating a countercurrent flow of... 

The catalytic distillation section uses a zeolite catalyst that is packaged into specially engineered bales. The catalyst bales function similarly as typical column structured packing and are designed to optimize both the distillation and the chemical reaction processes that occur in this portion of the alkylator. ... 

Phanse, G. Catalytic distillation the next step in aromatic alkylation. AIChE Spring Meeting New Orleans, LA, Mar 10-14, 2002. 

The first commercial and most well-known application of CD was in the production of MTBE. Besides etherification for the production of MTBE, CD could be applied in a number of processes such as alkylation, hydrogenation, isomerization, esterification, desulfurization, aldol condensation, oligomerization, hydration, hydrolysis, amination, and halogenation. Catalytic Distillation Technology (CDTECH), a partnership between ABB Lummus Global and Chemical Research and Licensing, is the leader in the development and commercialization of CD processes particularly related to the refining, petrochemical, and chemical industries. However, there are many more potential applications of CD that could be developed. 

A number of advantages of CD were obtained for the exothermic alkylation process and particularly noteworthy is the increased catalyst lifetime and enhanced selectivity to monoalkylated rather than dialkylated or trialkylated product. Catalytic Distillation Technology commercialized the production of ethylbenzene using the CD EB technology in 1994 at the Mitsubishi Petrochemical in Yokkaichi, Japan. The CD Cumene process was first brought onstream in 2000 at a capacity of 270,000 MTA by Formosa Chemicals and Fibre Corporation, Taiwan, and was expanded to double the capacity since 2004. 

Wang, E. Li, C. Simulation of suspension catalytic distillation for the synthesis of linear alkyl benzene. Chin. J. Chem. Eng. 2003,11 (5), 520-525. 

Other industrial processes that have taken advantage of the process intensification deriving from the introduction of reactive (catalytic) distillation are (i) production of high purity isobutene, for aromatic alkylation (ii) production of isopropyl alcohol by hydration of propylene (iii) selective production of ethylene glycol, which involves a great number of competitive reactions and (iv) selective desulfurization of fluid catalytic cracker gasoline fractions as well as various selective hydrogenations. Extraction distillation is also used for the production of anhydrous ethanol. 

If a chemical reaction occurs inside a distillation colmnn, with reactants and products subject to the usual requirements of the distillation process (phase eqniUbria, fractionation, and contacting device hydraulics), it is possible to shift the reaction eqnilibrimn in a favorable direction. A soluble or insoluble catalyst is likely to be involved thns, the operation is often known as catalytic distillation. Reactive distillation has been nsed snccessfnlly for etherification and esterification reactions and, to some extent, for alkylation, nitration, and amidation reactions. In most applications, the reaction has occurred in the liqnid phase, and an example of this application, where methyl acetate is produced from methanol and acetic acid nsing a solnble catalyst, has been described in detail. Flows for a generalized reactive colmnn are shown in Figm-e 12.21. 

Data were calculated for different types of refineries all having primary (crude oil) distilling capacities in the order of 5 million tonnes/annum, followed by various configurations of secondary upgrading facilities (reformer, catalytic cracker, alkylation, etc.) gasoline production was about 700,000 tons/annum in each case. 

Pentylamine Petroleum distillates, acid-treated middle Petroleum distillates, alkylate Petroleum distillates, catalytic reformer fractionator residue, low boiling Petroleum distillates, heavy hydrotreated naphthenic Petroleum distillates, heavy thermal cracked Petroleum distillates, hydrotreated light, low-boiling Petroleum distillates, hydrotreated middle Petroleum distillates, light hydrocracked Petroleum raffinates, sorption process... 

Certain fractions from the distillation of crude oil are further refined in thermal cracking (visbreaking), coking, catalytic cracking, catalytic hydrocracking, alkylation. 

A similar benzene alkylation process is being used by CDTECH in a catalytic distillation column (Called Catstill) (Dixon, 1989). In this case, the reformate does not have to be split prior to the reaction. Rather the entire reformate is sent to the bottom of the tower (Figure 6) where it is fractionated. FCC off-gas is then added ftirther up the column where it is reacted... 

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