Mobil/Badger ethylbenzene process

Two catalysts have emerged as commercially viable. The Mobil—Badger ethylbenzene process, which has been in commercial use since 1980, employs a ZeoHte catalyst and operates in the gas phase. A Hquid-phase ethylbenzene process joindy Hcensed by Lummus and UOP uses a Y-type ZeoHte catalyst developed by Unocal. This Hquid-phase process was commercialized in 1990. The same Y-type ZeoHte catalyst used for the production of ethylbenzene is being offered for the production of cumene but has not yet been commercialized. 

Mobil/Badger Ethylbenzene Benzene, polymer-grade ethylene EBMax process uses proprietary Mobil MCM-22 zeolite catalyst low capital cost 10 2000... 

Modem alkylation processes make use of solid catalysts based on zeolites. According to different technologies, the reaction can be performed in vapour or liquid phase. The selection of a suitable chemical reactor for ethylbenzene is discussed in the Example 8.3. A conceptual flowsheet is depicted in Fig. 7.31 for a vapour-phase process (Mobil-Badger), one of the most widely used. The reactor works at 390-440 C and 0.6-3 MPa. Besides the main product ethylbenzene (EB), polyethylbenzenes (PEB) are formed, their amount depending on the reaction conditions. Large excess of benzene, over 6 1, is needed to shift the equilibrium to the desired product. The reaction mixture is sent to the separation section. Final yield can increase over 99% by converting PEB s to EB in a separate transalkylation reactor. 

Figure 7.31 Vapour-phase Mobil-Badger ethylbenzene process...

Examples of commercial processes that use zeolitic catalysts for the alkylation of aromatics include the Mobil-Badger ethylbenzene process and the... 

The deactivation problem was overcome by using ZSM-5 as catalyst through the Mobil-Badger ethylbenzene synthesis. At present, more than ten plants are using this process, which works at 370 C, 14-27 bars. Diethylbenzene is the main subproduct, and its production is strongly decreased by adjusting the benzene ethylene ratio (208,209). 

In 1976, the Mobil/Badger ethylbenzene process was announced.This is a vapor-phase, fixed-bed process that utilizes ZSM-5. Because of the unique characteristics of the catalysts, aging rate is low and yields of nonselective byproducts are also low. The first commercial unit with a capacity of 50,000 t/y was streamed by the American Hoechst Corp. in 1980. Alkylation is carried out in the gas-phase at about... 

Vapor-Phase Processes. Although vapor-phase alkylation has been practiced since the early 1940s, it could not compete with Hquid-phase processes until the 1970s when the Mobil—Badger vapor-phase ethylbenzene process was introduced (Eig. 4). The process is based on Mobil s ZSM-5 zeohte catalyst (38,52,53). The nonpoUuting and noncorrosive nature of the process is one of its major advantages over the AlCl hquid-phase system. 

Eig. 4. Mobil—Badger process for ethylbenzene production H = heater Rx = reactor P = prefractionator BC = benzene recovery column ... 

Fig. 1. Mobil-Badger vapor-phase ethylbenzene process where PEB = polyethylbenzene.

ABB Lummus Crest Inc. and Unocal Corp. have Hcensed a benzene alkylation process usiag a proprietary zeoHte catalyst. Unlike the Mobil-Badger process, the Unocal-Lummus process is suitable for either ethylbenzene or cumene manufacture (27,28). 

All lation. An exceUent example of alkylation is the Mobil-Badger process, which uses ZSM-5-type zeoHte to produce ethylbenzene by alkylation of benzene with ethylene (12,40) ... 

Among the wide variety of organic reactions in which zeolites have been employed as catalysts, may be emphasized the transformations of aromatic hydrocarbons of importance in petrochemistry, and in the synthesis of intermediates for pharmaceutical or fragrance products.5 In particular, Friede 1-Crafts acylation and alkylation over zeolites have been widely used for the synthesis of fine chemicals.6 Insights into the mechanism of aromatic acylation over zeolites have been disclosed.7 The production of ethylbenzene from benzene and ethylene, catalyzed by HZSM-5 zeolite and developed by the Mobil-Badger Company, was the first commercialized industrial process for aromatic alkylation over zeolites.8 Other typical examples of zeolite-mediated Friedel-Crafts reactions are the regioselective formation of p-xylene by alkylation of toluene with methanol over HZSM-5,9 or the regioselective p-acylation of toluene with acetic anhydride over HBEA zeolites.10 In both transformations, the p-isomers are obtained in nearly quantitative yield. 

EBMax A continuous, liquid-phase process for making ethylbenzene from ethylene and benzene, using a zeolite catalyst. Developed by Raytheon Engineers and Constructors and Mobil Oil Corporation and first installed at Chiba Styrene Monomer in Japan in 1995. Generally similar to the Mobil/Badger process, but the improved catalyst permits the reactor size to be reduced by two thirds. 

The reachon of benzene with ethylene or propylene to form ethylbenzene or isopropylbenzene (cumene) is an industrially important transformahon, with ethylbenzene as the key building block for polystyrene and cumene as the feedstock for phenol produchon [55]. Fthylbenzene was originally produced with a Lewis acid catalyst consishng of AlCfi or a Bronsted acidic solid phosphoric acid (SPA) catalyst [56]. Both catalyst systems suffered from equipment corrosion so, in the 1980s the Mobil-Badger vapor phase alkylation process was introduced, which... 

A more recent development in ethylbenzene technology is the Mobil-Badger process,161,314-316 which employs a solid acid catalyst in the heterogeneous vapor-phase reaction (400-45O C, 15-30 atm). A modified H-ZSM-5 catalyst that is regenerable greatly eliminates the common problems associated with... 

Zeolite-Based Alkylation. Zeolites have the advantage of being noncot-rosive and environmentally benign. The Mobil-Badger vapor-phase ethylbenzene process was ihe lirsl zeolite-based process to achieve commercial success. It is based on a synthetic zeolite catalyst. ZSM-5. and has the desirable characteristics of high activity, low oligomerization, and low coke formation. See also Molecular Sieves. 

In the EBMax process, benzene is fed to the bottom of the liquid-filled multibed reactor. Ethylene is co-fed with the benzene and also between the catalyst beds. Polyethylbenzenes, which are almost exclusively diethylbenzenes, undergo transalkylation with benzene in a second reactor. Mobil-Badger offers both liquid phase and vapor phase transalkylation processes. The vapor phase process removes benzene feed coboilers such as cyclohexane and methylcyclopentane as well as propyl and butylbenzenes. Because the EBMax process produces very low levels of propyl and butylbenzenes, for most applications, the more energy efficient liquid phase process is preferred. Worldwide, there are currently ten licensed EBMax units with a cumulative ethylbenzene production capacity of five million metric tons per year. 

Application Process to manufacture styrene monomer (SM) by dehydrogenating ethylbenzene (EB) to styrene. Feedstock EB is produced by alkylating benzene with ethylene using the Mobil/Badger EBMax process. 

Figure 2.29 (a) Mobil/Badger s EBMax and (b) CDTECH EB processes for ethylbenzene (EB) production by benzene alkylation. Source adapted from Woodle [226]. 

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