MTBE decomposition

In conclusion, MTBE decomposition may be performed using reactive distillation equipment. The top product is fairly pure isobutene and will contain some methanol, which has to be separated downstream using conventional technology. 

Felthouse and Mills (321) report the amination of methyl ferf-butyl ether (MTBE) and isobutene to fert-butylamine using alumino- and borosilicate pentasil molecular sieve catalysts. The ether and alkene amination reactions were found to proceed preferentially under SCF conditions at temperatures on the order of 330°C and pressures greater than 193 bar. The smdy showed that MTBE can be used as a substitute raw material for terf-butylamine manufacture, but MTBE decomposition products of isobutene, methanol, and methanol conversion products are produced that require a more complicated product separation process than with isobutene as the only C4 substrate. 

L. Doron and S. Jose, Apparatus for producing phenol using reactive distillation, US Patent 6,411,252 (2002). K. J. Huang and S. J. Wang, Design and control of a methyl tertiary butyl ether (MTBE) decomposition reactive distillation colunm, Ind. Eng. Chem. Res. 46, 2508-2519 (2007). 

Shell-and tube-membrane reactor for pervaporation-assisted MTBE decomposition. (Adapted from Choi et al. Reprinted with permission from Elsevier, Copyright (2001).)... 

HuelsAG Isobutylene Methyl tertiary butyl ether (MTBE) Catalytic decomposition, high selectivity, high purity 1 1988... 

Methyl Ter Butyl Ether (MTBE), which is obtained by the action of methanol on isobutene in a C4 cut, is a compound of vital interest to refiners because of its antiknock properties, which allow it to improve the quality of commercial gasolines, and the possibility of introducing methanoHndirectly into them. It is also a valuable intermediate for petro emicals, in so far as its decomposition leads to the r eneration of the starting olefin in a high degree of purin% and because, by ensuring the virtually complete conversion of the isobutene, etherification facilitates subsequent separation operations on the residual C4 cut Hence two steps must be considered from this standpoint ... 

This review concerns the synthesis, characterization, and catalytic activity of microporous ferrierite zeolites and octahedral molecular sieves (QMS) and octahedral layer (OL) complexes of mixed valent manganese oxides. The ferrierite zeolite materials along with borosilicate materials have been studied as catalysts for the isomerization of n-butenes to isobutylene, which is an important intermediate in the production of methyltertiarybutylether (MTBE). The CMS materials have tunnels on the order of 4.6 to 6.9 A. These materials have been used in the total oxidation of CO to C02, decomposition of H2O2. dehydrogenation of CeHi4, C0H14 oxidation, 1-C4H3 isomerization, and CH4 oxidation. The manuscript will be divided into two major areas that describes zeolites and OMS/OL materials. Each of these two sections will include a discussion of synthesis, characterization, and catalytic activity. 

The vapor-phase decomposition of methyl-/-butyl ether (MTBE) into methanol and isobutene was examined in a shell- and tube-type catalytic membrane reactor by Choi and... 

Rg. 3.2. Process scheme of reactive separation for the production of isobutene by MTBE synthesis and subsequent decomposition of MTBE ((18), reprinted from Chem. Eng. Sci., Vol 57, Beckmann et al., Pages 1525-1530, Copyright 2002, with permission from Elsevier Science)... 

By analogy with MTBE synthesis, the decomposition of MTBE is also an acid-catalyzed and equilibrium-limited reaction. Ion-exchange resins were found to be suitable for this reaction. Besides catalyst activity and selectivity, a major requirement is to provide a catalyst lifetime of the same scale of time as the period of plant turnaround. Otherwise, catalyst replacement would require a shutdown of the entire unit. However, the results of run-time testing experiments have shown that the ion-exchange catalyst used provides high stability for more than 8000 h. Only slight decreases in catalyst activity have been observed. 

Figure 6.30 Selective decomposition of MTBE to produce pure isobutene using a sulphonic add catalyst specifically only surface functionalised to allow only short residence time.

Decomposition of (MTBE A) into isobutene (B) and methanol (C) follows the reaction scheme below ... 

An example of the use of extractor-type PlMRs in reactions other than esterification is the gas-phase decomposition of MTBE catalysed by tung-stophosphoric acid. Lee et reported the use of closed-loop recycle membrane reactors by using polycarbonate, polyarylate or cellulose acetate membranes to selectively permeate the formed methanol in a flat membrane reactor configuration, with the catalyst packed in the retentate side and by using helium as sweep gas in the permeate side. The authors also used a tube-and-shell reactor configuration with the catalyst packed in the shell side being the sweep gas fed to the tube side. 

Lee J K, Song I K and Lee W Y (1995), An experimental study on the application of polymer membranes to the catalytic decomposition of MTBE (methyl fert-butyl ether) , Catal Today, 25,345-349. 

Choi J S, Song I K and Lee W Y (2000), Simulation and experimental study on the polymer membrane reactors for the vapor-phase MTBE (methyl tert-butyl ether) decomposition, Catal Today, 56,275-282. 

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