CDTech MTBE process

Figure 3.31 Flowsheet of the CDTech MTBE process. Source [51].

Figure 3.33 shows a schematic of the CDTech MTBE/ETBE/TAME process. This is essentially the same as the CDTech MTBE process presented earlier. The process is unique in the sense of using a boiling point reactor and catalytic distillation (CD) [61]. The C4 feed and methanol is fed to the boiling point reactor (1). This is a fixed-bed downflow adiabatic reactor, in which the liquid is heated to its boiling point by the heat of reaction and... 

Should MTBE be banned, what would be the logical replacement(s) There are several options available. Several refiners opted to build MTBE capacity and avoid purchasing the ether on the open market. MTBE units were an option to use the facility s isobutylenes. Several licensed processes can be used to convert existing MTBE units. Kvaerner and Lyondell Chemical Co. offer technologies to convert an MTBE unit to produce iso-octane, as shown in Fig. 18.27.12 Snamprogetti SpA and CDTECH also have an iso-octene/iso-octane process. These processes can use various feedstocks such as pure iso-butane, steam-cracked C4 raffinate, 50/50 iso-butane/iso-butene feeds, and FCC butane-butane streams. The process selectively dimerizes C4 olefins to iso-octene and then hydrogenates the iso-octene (di-iso-butene) into iso-octane. The processes were developed to provide an alternative to MTBE. The dimerization reactor uses a catalyst similar to that for MTBE processes thus, the MTBE reactor can easily be converted to... 

Figure 3.33 Flowsheet of the CDTech MTBE/ETBE/TAME process. (1) boiling point reactor, (2) CD column, (3) extraction column, (4) methanol recovery column. Source [61].

CDTECH MTBE Mixed C hydrocarbons High-conversion catalytic distillation process for MTBE using C s and methanol 107 2000... 

CDTECH/Snamprogetti SpA Isobutylene Mixed C4 hydrocarbons Integrated MTBE and MTBE backcracking processes to selectively recover high-purity (99.9%) isobutylene 7 1991... 

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. 

CDTech uses catalytic distillation to convert isobutene and methanol to MTBE, where the simultaneous reaction and fractionation of MTBE reactants and products takes place [51], A block diagram of this process is shown in Figure 3.31. The C4 feed from catalytic crackers undergoes fractionation to extract deleterious nitrogen compounds. It is then mixed with methanol in a BP reactor where 90% of the equilibrium reaction takes place. The reactor effluent is fed to the catalytic distillation (CD) tower where an overall isobutene conversion of 97% is achieved. The catalyst used is a conventional ion-exchange resin. This process selectively removes MTBE from the product to overcome the chemical equilibrium limitation of the reversible reaction. The MTBE product stream is further fiactionated to remove pentanes, which are sent to gasoline blending, whereas the raffinate from the catalytic distillation tower is washed with water and then fractionated to recover the methanol. 

CDTECH Isobutylene MTBE Back-cracking process yields high-purity isobutylene (99.9%) and methanol 8 1997... 

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