Alcohol isobutyl

EPA Priority Pollutant under Solid and Hazardous Waste Category RCRA Hazardous Waste Number U140 

Synonyms 2-methyl-1-propanal isobutanol isopropyl carbinol 

Isobutanol is widely used in the production of isobutyl acetate for lacquers, isobutyl phthalate for plasticizers as a solvent for plastics, textiles, oils, and perfumes and as a paint remover. 

Isobutanol forms isobutylamine (toxic—erythema and blistering) with NH3 isobutyl chlorocarbonate, (CH3 )2CH—CH2—COOCl (eye and mucous membrane irritant) with phosgene and isobutyraldehyde (flammable) on air oxidation at 300°C (572°F) in the presence of Cu. 

Inhalation causes eye and throat irritation and headache. Ingestion may cause depression of the central nervous system. It is an irritant to the skin, causing cracking. Target organs are the eyes, skin, and respiratory system. 

Water Less than 0.05% by Karl Fischer titration Ultraviolet absorbance  

Refractive Index 1.3959 0.0011 at 20 C Bolling range 108-109 C Residue Less than five mg/1 Purity Greater than 99.0% by gc analysis 

Halonethanes Less than one ppb available on special ordar 

Electron capture gc No residue peaks greater than 4 ug/1 as heptachlor apoxlda. 

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Isobutyl alcohol, isobutanol, 2-methyl-propanol, isopropyl carbinol, Me2CHCH20H. B.p. 108°C. Occurs in fusel-oil. Oxidized by potassium permanganate to 2-methyl-propanoic acid dehydrated by strong sulphuric acid to 2-methylpropene. 

Referring to Fig. IV-4, the angles a and /3 for a lens of isobutyl alcohol on water are 42.5° and 3°, respectively. The surface tension of water saturated with the alcohol is 24.5 dyn/cm the interfacial tension between the two liquids is 2.0 dyn/cm, and the surface tension of n-heptyl alcohol is 23.0 dyn/cm. Calculate the value of the angle 7 in the figure. Which equation, IV-6 or IV-9, represents these data better Calculate the thickness of an infinite lens of isobutyl alcohol on water. 

Methyl 1 propanol Isobutyl alcohol or 2 methylpropyl alcohol 2 Methyl 2 propanol tert Butyl alcohol or 1 1 dimethylethyl alcohol... 

Isobutyl alcohol [78-83-1] forms a substantial fraction of the butanols produced by higher alcohol synthesis over modified copper—zinc oxide-based catalysts. Conceivably, separation of this alcohol and dehydration affords an alternative route to isobutjiene [115-11 -7] for methyl /-butyl ether [1624-04-4] (MTBE) production. MTBE is a rapidly growing constituent of reformulated gasoline, but its growth is likely to be limited by available suppHes of isobutylene. Thus higher alcohol synthesis provides a process capable of supplying all of the raw materials required for manufacture of this key fuel oxygenate (24) (see Ethers). 

The reaction of V2O5 with H PO to form VOHPO O.5H2O can be carried out in either an aqueous or organic medium such as isobutyl alcohol [78-83-1] (70,123). Two possible routes are as follows. 

Most large-scale industrial methacrylate processes are designed to produce methyl methacrylate or methacryhc acid. In some instances, simple alkyl alcohols, eg, ethanol, butanol, and isobutyl alcohol, maybe substituted for methanol to yield the higher alkyl methacrylates. In practice, these higher alkyl methacrylates are usually prepared from methacryhc acid by direct esterification or transesterification of methyl methacrylate with the desired alcohol. 

Formaldehyde. Pure formaldehyde, CH2O, is a colorless, pungent smelling reactive gas (see Formaldehyde). The commercial product is handled either as soHd polymer, paraformaldehyde (13), or in aqueous or alcohoHc solutions. Marketed under the trade name Formcel, solutions in methanol, / -butanol, and isobutyl alcohol, made by Hoechst-Celanese, are widely used for making alcohol-modified urea and melamine resins for surface coatings and treating textiles. 

A wide selection of amino resin compositions is commercially available. They are all alkylated to some extent in order to provide compatibiUty with the other film formers, and formulation stabiUty. They vary not only in the type of amine (melamine, urea, ben2oguanamine, and glycolutil) used, but also in the concentration of combined formaldehyde, and the type and concentration of alkylation alcohol (/ -butanol, isobutyl alcohol, methanol). 

The amino group is readily dia2oti2ed in aqueous solution, and this reaction forms a basis for the assay of sulfas. Aldehydes also react to form anils, and the yellow product formed with 4-(dimethylamino)hen2a1dehyde can be used for detection in thiu-layer and paper chromatography. Chromatographic retention values have been deterrnined in a number of thiu layer systems, and have been used as an expression of the lipophilic character of sulfonamides (23). These values have corresponded well with Hansch lipophilic parameters determined in an isobutyl alcohol—water system. 

Factors affecting the accumulation of ansamitocins P-2, P-3, and P-4 in JSbocardia sp. C-15003 have been studied (246) the addition of isoleucine, propionate, ptopionaldehyde, or -ptopyl alcohol to the fermentation medium resulted in the increased production of P-2 the addition of valine, isobutyrate, isobutyraldehyde, or isobutyl alcohol increased the production of P-3, reaching more than 90% of the total ansamitocins produced and the addition of leucine, isovalerate, isovaleraldehyde, or isoamyl alcohol increased the production of P-4. 

The most common chromatogram in the distilled spirits industry is the fusel oil content. This consists of / -propyl alcohol, isobutyl alcohol, and isoamyl alcohol. Other common peaks are ethyl acetate, acetaldehyde, and methanol. The gc columns may be steel, copper, or glass packed column or capillary columns. Additional analyses include deterrninations of esters, total acids, fixed acids, volatile acids, soHds or extracts (used to determine... 

Common Name CAS Registry Number -Butyl alcohol [71-36-3] Isobutyl alcohol [78-83-1] j -Butyl alcohol [78-92-2] /-Butyl alcohol [75-65-0]... 

Fig. 2. Liquid viscosity of butyl alcohols A, 1-butanol B, isobutyl alcohol C, 2-butanol D, /-butyl alcohol.

Butanol and isobutyl alcohol are aminated with ammonia over alumina at 300—350°C to give the corresponding mono-, di-, and tributylainines. 

The principal commercial source of 1-butanol is -butyraldehyde [123-72-8] obtained from the Oxo reaction of propylene. A mixture of n- and isobutyraldehyde [78-84-2] is obtained in this process this mixture is either separated initially and the individual aldehyde isomers hydrogenated, or the mixture of isomeric aldehydes is hydrogenated direcdy and the n- and isobutyl alcohol product mix separated by distillation. Typically, the hydrogenation is carried out in the vapor phase over a heterogeneous catalyst. For example, passing a mixture of n- and isobutyraldehyde with 60 40 H2 N2 over a CuO—ZnO—NiO catalyst at 25—196°C and 0.7 MPa proceeds in 99.95% efficiency to the corresponding alcohols at 98.6% conversion (7,8) (see Butyraldehydes Oxo process). 

Commercial isobutyl alcohol is made almost exclusively from the hydrogenation of isobutyraldehyde obtained by the hydroformylation of propylene. However, this alcohol is also commonly obtained as a coproduct in the Eischer Tropsch synthesis of methanol (16,17). 

Historically, isobutyl alcohol was an unwanted by-product of the propylene Oxo reaction. Indeed, isobutyraldehyde the precursor of isobutyl alcohol was occasionally burned for fuel. However, more recentiy isobutyl alcohol has replaced -butyl alcohol in some appHcations where the branched alcohol appears to have preferred properties and stmcture. However, suppHes of isobutyl alcohol have declined relative to overall C-4 alcohols, especially in Europe, with the conversion of many Oxo plants to rhodium based processes which give higher normal to isobutyraldehyde isomer ratios. Further the supply of isobutyl alcohol at any given time can fluctuate greatly, since it is the lowest valued derivative of isobutyraldehyde, after neopentyl glycol, methyl isoamyl ketone and certain condensation products (10). 

The principal industrial appHcation for isobutyl alcohol is as a direct solvent replacement for 1-butanol. It is also used as a process solvent in the flavor and fragrance, pharmaceutical, and pesticide industries. The maximum employment of isobutyl alcohol was in the mid-1980s when it had a distinct price advantage over 1-butanol (10). More recently, however, with increased demand for other value added derivatives of isobutyraldehyde, the price differential between isobutyl and -butyl alcohols has diminished resulting in a switching back by some consumers to 1-butanol. 

Some efforts were made in the early 1980s to employ isobutyl and -butyl alcohols as octane extenders in gasoline. American Methyl Corporation in 1983, under a special waiver of the 1977 Clean Air Act (24), marketed a gasoline blend called Petrocoal containing methanol and a C-4 alcohol which was principally isobutyl alcohol. About 10,000 t of isobutyl and 5000 t of -butyl alcohol were consumed in this appHcation (10). In 1984, the EPA attempted to rescind this waiver and demand for isobutyl alcohol as a gasoline additive dropped to 136.3 t (10). Ultimately, the waiver was rescinded and no isobutyl or -butyl alcohol has been marketed for gasoline additive end use since 1984. 

Sulfuric acid is about one thousand times more reactive with isobutylene than with the 1- and 2-butenes, and is thereby very useful in separating isobutylene as tert-huty alcohol from the other butenes. The reaction is simply carried out by bubbling or stirring the butylenes into 45—60% H2SO4. This results in the formation of tert-huty hydrogen sulfate. Dilution with water followed by heat hydrolyzes the sulfate to form tert-huty alcohol and sulfuric acid. The Markovnikov addition implies that isobutyl alcohol is not formed. The hydration of butylenes is most important for isobutylene, either directiy or via the butyl hydrogen sulfate. 

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