Alcohols tertiary butyl ethers

Ethyl Tertiary-Butyl Ether. Similar to methanol in the MTBE reaction, ethanol can react with isobutylene to produce ETBE. Which alcohol is used to make the ether is highly dependent on the relative cost of the alcohols. To make ethanol more economically competitive with methanol, the federal tax credit for biomass-based ethanol used in fuel also appHes to ethanol used to make ETBE in the United States (24). 

Ethanol, or grain alcohol, is an alcohol fuel widely used as automotive fuel. It can be made from a variety of feedstocks, mainly grains, forest resides, and solid waste. It can be used in its pure form, but is more widely used in a blended form. Gasoline blends (90% gasoline/10% ethanol) have been widely used in many areas of the country. Ethyl tertiary butyl ether (ETBE) is a feedstock for reformulated gasoline based on ethanol. 

Cation-exchange resins are used as catalysts in the produdion of MTBE (methyl tertiary-butyl ether, 2-methoxy-2-methylpropane) and various other oxygenates and, lately, also in the dimerization of isobutene [30]. Other commercial applications of the cation-exchange resins indude dehydration of alcohols, alkylation of phenols, condensation readions, alkene hydration, purification of phenol, ester hydrolysis and other reactions [31]. The major producers of ion-exchange resins are Sybron Chemicals Incorporated [32] (Lewatit resins), Dow Chemical Company [33] (DOWEX resins), Purolite [28] (Purolite resins), and Rohm and Haas Company [27] (Amberlyst resins). 

Isobutylene is the most chemically reactive of the butylene isopiers. If the objective is just to get the isobutylene out of the C4 stream, it can be removed by reaction with methanol (CH3OH) to make MTBE (methyl tertiary butyl ether), by reaction with water to make TBA (tertiary butyl alcohol), by polymerization, or by solvent extraction. After that, butene-1 can be removed by selective adsorption or by distillation. That leaves the butene-2 components, together with iso- and normal butane, which are generally used as feed to an alkylation plant. 

Methanol, CH3OH, the simplest alcohol, is made by reacting CO and H2 at high pressures over a catalyst. Methanol is a liquid at room temperature and is highly toxic. It is used to make formaldehyde, acetic acid, and other chemical intermediates. It is also used as a feedstock for MTBE (methyl tertiary butyl ether), a gasoline-blending component. 

Oxygenated fuels Ethanol 10% (ElO), Methanol, Methyl tertiary butyl ether (MTBE), Ethyl tertiary butyl ether (ETBE), Tertiary butyl alcohol (TBA), and Tertiary amyl methyl ether (TAME)... 

A pilot-scale Rayox system, which included a GAC treatment component, was installed at the Charnock Wellfleld site in Santa Monica, California. Groundwater at the site was contaminated with methyl tertiary butyl ether (MTBE) and tertiary butyl alcohol (TBA). Capital costs for the proposed 3500 gpm full-scale system are projected to be 4 million to 5 million. These costs do not include expenses associated with installing the technology or purchasing property to house the system (40,000 ft are required). Operating costs are projected to be 1.50 to 1.75 per 1000 gal of water treated (D22276E, pp. 50, 51). 

The technology is applicable to chlorinated and nonchlorinated VOCs methyl tertiary butyl ether (MTBE) dichloroethylene (DCE), trichloroethylene (TCE), and tetrachloroethylene (per-chloroethylene, PCE) dichloroethane (DCA) vinyl chloride alcohols ethers ketones and halogenated and nonhalogenated paraffinic, olefinic, aliphatic, and aromatic hydrocarbons. It is very effective at treating benzene, toluene, ethylbenzene, and xylene (BTEX) compounds and any oxygenate, such as acetone or isopropanol. 

Methyl-tertiary-butyl ether (MTBE) is one of the leading chemicals currently being made from isobutylene (methyl propene) via the acid-catalyzed addition of methyl alcohol. MTBE has been added to gasoline as a required oxygenate. Eiowever, it is under attack as a groundwater contaminant and is being phased out. 

Methanol, also known as wood alcohol, is another widely discussed potential source (or carrier) of hydrogen.31 Chemically, methanol, ch oh, is a clear liquid, the simplest of the alcohols, with one carbon atom per molecule. Methanol is extensively used today— U.S. demand in 2002 exceeded 2 billion gallons. The largest U.S. methanol markets are for producing the gasoline additive mtbe (methyl tertiary butyl ether) as well as formaldehyde and acetic acid. 

There can be little doubt that oxygen-containing hydrocarbons (oxygenates) will play an increasingly prominent role as components of motor fuels and, potentially, as raw materials for other petrochemical-based processes. The last decade has seen increasing use of oxygenates, including alcohol blends and methyl tertiary butyl ether (MTBE), as octane... 

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... 

Catalysts containing niobia supported on various oxides have been the subject of considerable recent interest [1-4]. The molecular structures and reactivity of niobium oxides supported on alumina, titania, zirconia and silica have been intensively investigated over the last few years. Niobia supported on silica has been shown to be active for the dehydrogenation and dehydration of alcohols, photo-oxidation of propene and oxidative decomposition of methyl tertiary butyl ether. Titania supported niobia is active for the selective catalytic reduction (SCR) of NO by NH3. 

McGregor DB, Cruzan G, Callander RD, May K, Banton M (2005) The mutagenicity testing of tertiary-butyl alcohol, tertiary-butyl acetate, and methyl tertiary-butyl ether in Salmonella typhimurium. Mutat Res 565 181-189... 

Methanol, ethanol, and methyl tertiary butyl ether (MTBE) are OxHCs added to fuels to decrease tailpipe emissions of NMHCs and CO. Some alcohols, aldehydes, and ketones are emitted from biogenic sources others are also produced in the atmosphere through photochemical oxidation. The levels of some of the light OxHCs (e.g., acetaldehyde, methanol, ethanol, and acetone) are substantial. In the rural atmosphere, these can dominate the VOCs distribution (see,... 

Oxygenates such as methanol, methyl tertiary butyl ether (MTBE) and/or tert-butyl alcohol (TBA) are used as "selectivator" to improve selectivity of the dimerization reaction while avoiding formation of heavier oligomers. 

The pervaporation for the water-alcohol and methanol-methyl tertiary butyl ether (MTBE) mixture showed a decreased permeation flux and increased water content in the permeate for water-alcohol mixture. The complex membrane showed a high separation factor up to 4,000 and 19,000... 

The most important solvents to be treated are the light alcohols, ethanol, the propanols, and butanols. Other solvents are esters like ethyl and butyl acetate, ketones like acetone, butanone (MEK) or methyl isobutyl ketone, ethers like tet-rahydrofuran (THF) or methyl tertiary butyl ether, or acetonitrile, or mixtures of these solvents. The selectivity of the polymeric membranes for all components in such mixtures is high and fairly similar, multicomponent mixtures can thus... 

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