Iso-amylene

TAME can also be produced by the reaction of methanol with iso-amylenes. The reaction conditions are similar to those used with MTBE, except the temperature is a little higher ... 

The ether process combines an alcohol with an iso-olefin. In the United States, a weight percentage of oxygenate (2 wt.%) content is mandated for reformulated gasoline (RFG). The most common oxygenate currently used is methyl tertiary butyl ether (MTBE). Methanol and the iso-olefin form of isobutylene are reacted to form MTBE. Other alcohols, such as ethanol, may be reacted with iso-butylene to form ethyl tertiary butyl ether (ETBE). Methanol can be reacted with iso-amylene, another iso-olefin, to form tertiary amyl-methyl ether (TAME). Of all the mentioned ethers, MTBE is the one most widely used as a gasoline-blending component.16... 

Metbylbutylene-2 [Isopentene-2, p-iso-amylene, trimethiflethylene, isopropiflidenR-eihanc,... 

In order to simulate the RD column this was represented as an ensemble of three components corresponding to the software chemical operation modules available in HYSYS. The calculated iso-amylenes conversion was compared with measured values on a pilot plant RD unit. 

Due to the limited accuracy of instruments for flow rates measurement, the accuracy of experimental data is limited. An error of about 10 % in the evaluation of pilot plant iso-amylenes conversion has to be considered. 

The measured iso-amylenes conversion values in three runs of the pilot plant, under identical experimental conditions (Table 2) were 70.97 %, 81.26 % and 78.77 %. The simulated value, found for the same working conditions, is 76 %. As observed, taking into consideration the accuracy of the measurements, a fairly good agreement appears between the simulated and experimental conversion values. However, further improvements are needed concerning the kinetic data, the flow model of the reaction zone and the mass transfer limitations around the catalyst pellet. 

The final pressure-swing azeotropic distillation system presented in this chapter is the separation of pentanes from methanol. This application arises in the production of tert-amyl methyl ether (TAME), which is used as a high-octane gasoline blending component. TAME is produced in a reactive distillation column by the reaction of methanol with the unsaturated five-carbon iso-amylenes (2-methyl-1-butene and 2-methyl-2-butene). 

The process flowsheet has a prereactor, a reactive distillation column, and a methanol-recovery section. A methanol-recovery section is required because the inert C5 components coming in with the reactive iso-amylenes in the C5 fresh feed form azeotropes with methanol. The result is that a significant amount of methanol is present in the distillate from the reactive column. 

The ethers are manufactured by combining iso-olefms with alcohols. If the iso-olefm is isobutylene and the alcohol is methanol, the resultant ether is methyl tertiary butyl ether (MTBE). If die olefin is iso-amylene, one makes tertiary amyl methyl ether (TAME), and switching the alcohol to ethanol yields ethyl tertiary butyl ether (ETBE). 

The reaction is also liquid phase, being carried out under somewhat more severe conditions than MTBE. Reaction rates are slower for TAME than for MTBE and equilibrium conversion are lower. Conventional single-stage iso-amylene conversion is 65% (Chase, 1984). Catalytic distillation can improve the conversion and selectivity by continuous removal of the product TAME as it is being formed and shifting the TAME equilibrium. The combination of fixed bed recycle process followed by a catalytic distillation is claimed to achieve yields of TAME as high as 90% (D Amico, 1990). 

ISOMPLUS A process for isomerizing -butenes to isobutene and -pentane to iso-amylene, using aZSM-5 zeolite catalyst. Developed by CD Tech and Lyondell Petrochemical. One unit was operating in 1996. Used in their Channelview refinery, TX. 

Pentanone, see Methyl n-propyl ketone 3- Pentanone, see Diethyl ketone Pentene, see Amylene n-Pentyl acetate, see n-Amyl acetate sec-Pentyl acetate, see sec-Amyl acetate Pentyl alcohol, see n-Amyl alcohol Pentyl amine, see n-Amylamine iso-Pentyl nitrite, see Amyl nitrite Peracetic acid (40% acetic acid 1.23 41... 

Sulfuric acid and isoamylene under suitable conditions yield diisoamylene also. This polymerization reaction is used commercially in the formation of synthetic rubber from the octadiens. The specific action of the particular catalyst employed is shown also by the fact that iso-propyl bromide dissociated at the temperature of boiling amylene in the presence of asbestos, while the n-bromide did not. [D. Konowalow, Ber. 18, 2808 (1885).]... 

Aminothiarole n-Amy] acetate iso-Amvl acetate n-Atnyl alcohol 7-Amyl alcohol Inactive Amyl alcohol leo-Amy] alcohol sec-Amyl alcohol tert-Amyl alcohol n-Amylamine iso-Amylamine n-Amylbenzene iso-Amyl bromide iso-Amyl-n-butyrate iso-Amyl chlcu ide iso-Amyl cyanide iso-AmvIene Amylene bromide Aroylene chloride iso-Amyl ether iso-Amyl formate Amylidene chloride... 

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