Butyl alcohol, tertiary

Tertiary butyl alcohol, trimethyl carbinol, tertiary butanol. 2-methyl-2-propanol, Me3COH. Colourless prisms, m.p. 25°C, b.p. 83°C. Prepared by absorbing isobutene (2-methylpropene) in sulphuric acid, neutralizing and steam distilling the liquor. Converted to isobutene by heating with oxalic acid. Potassium-/-buloxide is a very strong base. 

The tendency to separate is expressed most often by the cloud point, the temperature at which the fuei-alcohol mixture loses its clarity, the first symptom of insolubility. Figure 5.17 gives an example of how the cloud-point temperature changes with the water content for different mixtures of gasoline and methanol. It appears that for a total water content of 500 ppm, that which can be easily observed considering the hydroscopic character of methanol, instability arrives when the temperature approaches 0°C. This situation is unacceptable and is the reason that incorporating methanol in a fuel implies that it be accompanied by a cosolvent. One of the most effective in this domain is tertiary butyl alcohol, TBA. Thus a mixture of 3% methanol and 2% TBA has been used for several years in Germany without noticeable incident. 

The reason for this is that reaction (i) is usually much slower than (ii) and (iii) so that the main reaction appears to be (Iv) (compare the preparation of tertiary butyl chloride from tertiary butyl alcohol and concentrated hydrochloric acid, Section 111,33). If the reaction is carried out in the presence of P3rridine, the latter combines with the hydrogen chloride as it is formed, thus preventing reactions (ii) and (iii), and a good yield of the ester is generally obtained. The differentiation between primary, secondary and tertiary alcohols with the aid of the Lucas reagent is described in Section III,27,(vii). 

The speed of the reaction depends both on the metal and on the alcohol, increasing as electropositivity iacreases and decreasiag with length and branching of the chain. Thus sodium reacts strongly with ethanol, but slowly with tertiary butyl alcohol. The reaction with alkaU metals is sometimes carried out ia ether, ben2ene, or xylene. Some processes use the metal amalgam or hydride iastead of the free metal. Alkaline earth metals and aluminum are often covered with an oxide film which hinders the reaction. 

Tertiary butyl alcohol (900 ml., 702 g., 9.47 moles) is dissolved in a solution prepared by mixing 28 ml. (0.50 mole) of concentrated sulfuric acid with 1.5 1. of water in a 5-1. round-bottomed flask (Note 1) equipped with a thermometer, stirrer, gas inlet tube, and two addition burets. One buret is charged with 86 ml. (1 mole) of 11.6iH hydrogen peroxide (Note 2), and the other with a solution of 278 g. (1 mole) of ferrous sulfate pentahydrate and 55.5 ml. (1 mole) of concentrated sulfuric acid in 570 ml. of water (Note 3). The reaction flask is swept out with nitrogen and cooled to 10° by means of an ice bath. Stirring is commenced and the two solutions are added simultaneously and equivalently over a period of 20 minutes. The temperature is held below 20°. 

The above-mentioned alcohols are by far the most common. Butyl alcohol is not as commonly used as the first four in the series, but it is used. Secondary butyl alcohol and tertiary butyl alcohol, so named because of the type of carbon atom in the... 

C4 cuts, after extraction of butadiene, are preferred as feed to isobutylene extraction units because the isobutylene concentration (about 30-40%) is higher than in C4 streams from catalytic cracking. The basic reaction in isobutylene extraction is the reversible hydration of isobutylene to tertiary butyl alcohol in the presence of sulfuric acid. 

On autoxidation by aeration in tertiary butyl alcohol containing potassium tert-butyl oxide, quininone yields quininic acid (98 per cent.) and meroquinenine terf-butyl ester, CgHi N. CO. O. C4H9, b.b. 127°/20 mm., dj 0-9832, [a]o° -(- 50-0° (EtOH), identified by hydrolysis to meroquinenine (meroquinene) and eonversion of this to the better-known ethyl ester (p. 438). (Doering and Chanley.)... 

A solution of 7.5 grams of retroprogesterone in 500 ml of freshly distilled tertiary butyl alcohol was refluxed with 12.75 grams of finely powdered chloranil, while stirring, for 5 hours in a nitrogen atmosphere. After cooling, 2 liters of water were added and extraction was performed three times with 200 ml of methylene dichloride. The combined extracts were then diluted with 1 liter of petroleum ether (40°-60°C) washed successively with 100 ml of diluted Na2S04, four times with 75 ml of 1 N NaOH, and then water to neutral reaction. 

Methyl acrylate, 28.0 g (0.4 mol) was added dropwise during one hour to a solution containing 54.8 g (0.4 mol) of isonicotinic acid hydrazide (isoniazid) and 10 ml of glacial acetic acid in 400 ml of tertiary butyl alcohol. The resulting solution then was heated for 18 hours on a steam bath. Concentration of the reaction mixture to 100 ml yielded 13.0 g of unreacted isonicotinic acid hydrazide. The filtrate was concentrated to a thick syrup which was triturated... 

To a stirred solution of 1.00 gram of 17/3-hydroxy-17o -methyl-4-androsteno[3,2-c] pyrazole in 200 ml of tetrahydrofuran and 400 ml of liquid ammonia was added 2.12 grams of iithium wire during 5 minutes. The dark biue mixture was stirred for 45 minutes. A solution of 40 ml of tertiary-butyl alcohol in 160 ml of diethyl ether was added with stirring. 

Figure 9-6. A simplified flow diagram of a tertiary butyl alcohol pilot plant.

Oxygen was added as oxygenated hydrocarbon components methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE), ethanol, methanol, and tertiary butyl alcohol (TBA). The properties of oxygenates, as they relate to gasoline blending, are shown in Table 10-1. 

The common names of 2-methyl-2-propanol are tertiary-butanol and tertiary-butyl alcohol (commonly shortened to tert-butanol and tert-butyl alcohol or even t-butanol and t-butyl alcohol). 

De Luca et al. [1.48] showed, that the addition of 5 % tertiary butyl alcohol (tBA) to aqueous sucrose and lactose solutions (up to 40 %) resulted in a frozen matrix, which could be easily freeze dried. De Luca demonstrated by DSC that the melting point rose distinctly (with 60 % solution to -10 °C), but the endothermic of melting returned to 25 %, indicating that not much water had frozen. In solutions with 5 % tBA the exothermic of crystallization became more visible and the melting of tBA could be recognized. 

Kasrajan, K., De Lucca, P. O. Thermal analysis of tertiary butyl alcohol-water system and its implication on freeze-drying. Pharm. Res. 12 (4), p. 484—90, 1995... 

Oesterle, J., Franks, F., Auffret, T. The influence of tertiary butyl alcohol and volatile salts on the sublimation of ice from frozen sucrose solution Implications for freeze drying. Pharmaceutical Developments and Technology, 3 (2), p. 175-183, 1998. Copyright 1998 by Marcel Dekker, Inc., New York, N. Y., USA... 

The method is quite reliable and has been used for the correlation of configurations of various tertiary butyl alcohol. In this connection some empirical rules have been formulated for certain type of deviatives. 

In the dimerization of isobutene, tertiary-butyl alcohol (TBA, 2-methyl-2-propanol) has a strong role in modifying the selectivity of the reaction to Cg hydrocarbons and limits further oligomerization to C12 and Ci6 hydrocarbons [34]. Also, in the etherification of glycerol with isobutene the addition of TBA has a clear effect on the selectivity and on hydrocarbon distribution. The selectivity to ethers increased and the fraction of the Cu and Ci6 hydrocarbons decreased while the concentration of TBA was increased from 0 to 2.6 mol.%. As a conclusion, the formation of C12 and C16 hydrocarbons can be prevented in two ways either TBA should be added to the reaction mixture or the reaction should be carried out at high temperatures [8]. 

G. B. Dutt, S. Doraiswamy and N. Periasamy, Molecular dynamics of polar dye probes in tertiary-butyl alcohol-water mixtures,/. Chem. Phys. 94, 5360-5368 (1991). 

Alcohols, their corresponding olefins and alkyl cations are in equilibrium, with the alcohol generally predominating over the olefin (Purlee et al., 1955 Taft and Riesz, 1955 Boyd et al., 1960). The alkyl cation concentration is extremely low and this species never exists as more than a transient intermediate whose relation to the solvent is little known. In 5% H2SO4 the ratio of alcohol to olefin is about 1200 to 1 at 50° for the isobutylene-tertiary butyl alcohol system (Taft and Riesz, 1955). As the temperature increases the ratio of alcohol to olefin at equilibrium decreases (Boyd et al., 1960). This can be illustrated by examining the position of equilibrium in equation (8). Values of Kp, [alcohol (1)]/ [olefin (g)], were shown to vary from 5 54 at 50° to 1-34 at 70°. The equilibrium constant [alcohol (l)]/[olefin (1)] can be calculated from... 

In this range of acidity the intermediate carbonium ions do not fragment to smaller species. Isobutylene (C4) produces Cg and C12 olefins but no C5, C(), C7, C9 Cio or Cu products. This lack of fragmentation has been demonstrated for the co-polymerization of secondary and tertiary butyl alcohols and for mixed butyl and amyl alcohols (Whitmore and Mixon, 1941 Whitmore et al., 1941). 

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. 

High purity isobutylene is used in numerous applications beside the polyisobutylene just mentioned butyl rubber, 0x0 alcohols, tertiary butyl alcohols, di- and tri-isobutylene and methyl methacrylate. 

One of the commercial benefits of this route is the value of the coproducts, tertiary butyl alcohol (TBA) when isobucane is used, and styrene when ethylbenzene is used. TBA also can be easily hydro-treated back to isobutane if a recycle stream for PO manufacture is more advantageous. 

Unfortunately, secondary and tertiary butyl alcohols (SBA and TBA) cannot be made by the Oxo process. Instead they are produced either by indirect or direct hydration of the corresponding olefin. Normal butylene gives SBA and isobutylene gives TBA. The processes are similar to the corresponding routes to IPA. 

In Asia, Asahl and Mitsubishi have commercialized a process using isobutylene or tertiary butyl alcohol to malce methacrolein. Then they further oxidize it to methacryiic acid, MAA, which is then esterified with methanol to MMA. The same process might eventually start with iso butane oxidation to bypass the olefin step. 

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