K-Butyl ether

J. B. Ott, K. N. Marsh, and A. E. Richards, "Excess Enthalpies, Excess Gibbs Free Energies, and Excess Volumes for (di-//-Butyl Ether-)- Benzene) and Excess Gibbs Free Energies and Excess Volumes for (di-n-Butyl Ether + Tetrachloromethane) at 298.15 and 308.15 K", /. Chem. Thermodyn., 13, 447-455 (1981). 

Meiliyi ten-butyl ether (j key iiniikntx. k ingredient in gasoline)... 

Baretto RD, KA Gray, K Anders (1995) Photocatalytic degradation of methyl-ferf-butyl ether in TiOj slurries a proposed reaction scheme Water Res 29 1243-1248. 

Steffan RJ, K McClay, S Vainberg, CW Condee, D Zhang (1997) Biodegradation of the gasoline oxygenates methyl ferf-butyl ether, ethyl ferf-butyl ether, and amyl tcrt-butyl ether by propane-oxidizing bacteria. Appl Environ Microbiol 63 4216-4222. 

Hatzinger PB, K McClay, S Vainberg, M Tugusheva, CW Condee, RJ Steffan (2001) Biodegradation of methyl terf-butyl ether by a pure bacterial culture. Appl Environ Microbiol 67 5601-5607. 

R. A. Deeb, H. Y. Hu, J. R. Hanson, K. M. Scow, and L. Alvarez-Cohen. Substrate interactions in BTEX [benzene, toluene, ethylbenzene, and xylene] and MTBE [methyl tert-butyl ether] mixtures by an MTBE-degrading isolate. Environ Sci Technol, 35(2) 312-317, 2001. 

Jhanson R, Ackerman CE, Scow KM (1999) Biodegradation of methyl ter/-butyl ether by abacterial pure culture. Appl Environ Microbiol 65 4788-4792 Kanaly RA, Bartha R, Watanabe K, Harayama S (2000) Rapid mineralization of benzo[a]pyrcnc by a microbial consortium growing on diesel fuel. Appl Environ Microbiol 66 4205-4211... 

Kortiim and Vogel (1955) drew attention to the fact that the spectroscopic determination of the K-values suffered from a degree of uncertainty because of the unknown extinction coefficients of the complexes. For this reason, the authors preferred to determine the constant by means of a solubility method which had already proved of value in analogous investigations of the systems dioxan-iodine and methyl butyl ether-iodine (Kortiim and Kortiim-Seiler, 1950). In this method the solubility of iodine is determined as a function of the composition of solvent mixtures. values obtained by this method are summarized in Table 13. 

Thermodynamic consistency of data on solutions can be tested by plotting In (71/72) against Xi and seeing whether the area between Zi = 0 and 0.5 is equal and opposite in sign to the area between 0.5 and 1.0. Such a plot is indicated in Figure 16.5 for solutions of methyl f-butyl ether and chloroform at 313.5 K (5). 

We shall use the data of Mato et al. [2] for the vapor pressure and vapor composition of mixtures of methyl tert-butyl ether [1] and chloroform (2) at 313.15 K to illustrate the procedures used to calculate as a function of composition. These data are plotted in Figure 17.3. 

Figure 17.3. Data for vapor pressure and composition of solutions of methyl rert-butyl ether Pi and chloroform p2 at 313.15 K. Data from Ref. 2.

TABLE 17.3. Vapor Pressure and Composition for Solutions of Methyl f-Butyl Ether and Acetonitrile at 313.15 K. 

The data in Table 17.3 are for vapor pressure and vapor and liquid composition of solutions of methyl tert-butyl ether (1) and acetonitrile (2), (9). The symbol Xi represents the mole fraction of (1) in the liquid phase, and yi represents the mole fraction of (1) in the vapor phase. P is the equilibrium vapor pressure of the solution. The temperature is 313.15 K. 

TABLE 18.8. Excess Volumes of Solutions of Methyl tert-Butyl Ether and Chloform at 198.15 K... 

Bouzas, A., Burguet, M.C., Montdn, J.B., and Munoz, R. Densities, viscosities, and refractive indices of the binary systems methyl fert-butyl ether -t 2-methylpentane, + 3-methylpentane, + 2,3-dimethylpentane, and + 2,2,4-trimethylpentane at 298.15 K, / Chem. Eng. Data, 45(2) 331-333, 2000. 

Munoz, R., Burguet, M.C., Morlanes, N., and Garci a-Usach, F. Densities, refractive indices, and excess molar volumes of binary and tertiary systems containing isobutyl alcohol, ethanol, 2-methylpentane, and methyl ferf-butyl ether at 298.15 K, J. Chem. Eng. Data, 45(4) 585-589, 2000. 

Shaffer. K.L. and Uchrin, C.G. Uptake of methyl tertiary butyl ether (MTBE) by groundwater solids. Bull. Environ. Contam. Toxicol, 59(5) 744-749, 1997. 

Wallington, T.J., Dagaut, P., Liu, R., and Kurylo, MJ. Gas-phase reactions of hydroxy radicals with the fuel additives methyl f-butyl ether and f-butyl alcohol over the temperature range 240-440 K, Environ. Sci. TechnoL, 22(7) 842-844, 1988c. Wallington, T.J. and Japar, S.M. Atmospheric chemistry of diethyl ether and ethyl ferf-butyl ether. Environ. Sci TechnoL, 25(3) 410-415, 1991. 

The LLE for another ternary system, ethyl terf-butyl ether (ETBE) -t ethanol -l- [C4CiIm][TfO], at 298.15 K was studied by Arce et al. [35]. To determine the tie-line compositions, they used the NMR spectroscopy. The values of the solute distribution ratio fi = XEtoH V. EtoH / where II refers to an IL-rich phase) and selectivity (S = /SEtoH// EXBE) were calculated from tie-line data. In general, both the solute distribution ratio and the selectivity decreased as the molar fraction of efhanol in the organic-rich phase increased, the maximal values being ca. 3.5 and ca. 22, respectively. The ETBE + ethanol + IL system was compared to the ETBE + ethanol + water system. 

This is also true of vinyl alkyl ethers. Thus the Tg of polyethyl vinyl ether is lower (244 K) than the Tg of polymethyl vinyl ether (263 K). However, branched alkyl groups increase the Tg, mainly through imparted steric restrictions. Hence the Tg values of polyvinyl -butyl ether, polyvinyl isobutyl ether, and polyvinyl /er/-butyl ether are 221, 255, and 361 K, respectively. 

The synthesis of methyl /-butyl ether (MTBE) from isobutylene and methanol on TS-1 has been investigated. This reaction is catalyzed by acids and the industrial production is carried out with sulfonic acid resin catalysts. It has been reported that at 363-383 K the reaction proceeds in the presence of the acidic HZSM-5, but also on TS-1, which is much more weakly acidic. However, the characterization of the catalysts used is not completely satisfactory for instance, the IR spectra reported do not show the 960-cm 1 band that is always present in titanium-containing silicas. It is therefore possible that the materials with which the reaction has been studied are not pufe-phase TS-1. The catalytic activity for MTBE synthesis is, in any case, an interesting result, and further investigations with fully characterized catalysts are expected to provide a satisfactory interpretation of these results (Chang et al., 1992). 

Fig. 3. Kinetics of n-butyl alcohol consumption (a) and dehydration (b) in HZSM-5 (flow microreactor, sample I, 399 K) (A) Water ( ) di-n-butyl ether, n-butene (X) unreacted n-butyl alcohol.

For instance, the activation energy for butene formation from n-butyl alcohol is 140 lOkJmol-1 on HZSM-5 and only 95 lOkJmol-1 on AAS. At 378 K, 94% ether plus 6% butene are formed over HZSM-5, whereas 43% ether and 57% butene are formed over AAS. Bearing in mind that butyl alcohol molecules, as well as those of intermediates and products of their dehydration, have dimensions closely similar to the diameter of the zeolite channels, we infer that a liquid-like packing of butyl alcohol molecules and other reaction participants occurs in the channels (as schematized in Fig. 5). We opine that some specific ordering of the adsorbed species in the catalyst channels may be induced by hydrogen bonding and hydrophobic interactions between them. 

The rate constants for the reactions between OH and a range of ethers and hydroxy ethers have been reported at 298 K233 as well as those for reactions between dimethyl ether and methyl f-butyl ether over the range 295-750 K.234 Data from the former study show deviations from simple structure-activity relationships which were postulated to arise due to H-bonding in the reaction transition states.233 The atmospheric lifetime of methyl ethyl ether has been determined to be approximately 2 days.235 Theoretical studies on the H-abstraction from propan-2-ol (a model for deoxyribose) by OH have been reported using ab initio methods (MP2/6-31G ).236 The temperature dependence (233-272 K) of the rate coefficients for the reaction of OH with methyl, ethyl, n-propyl, n-butyl, and f-butyl formate has been measured and structure-activity... 

N. K. Kochetkov, V. A. Derevitskaya, and E. M. Klimov, Synthesis of glycosides via tert.-butyl ethers of alcohols, Tetrahedron Lett., 10 (1969) 4762-4769. 

Suzuki et al. [Ill] screened three solvents—methylene chloride, diethyl ether, and benzene—to determine their ability to produce optimum elution of phthalic acid monoesters sorbed on a styrene divinylbenzene polymer (Figure 2.40). The effect of elution solvent strength on the recovery of the free acid form of the monomethyl (MMP), ethyl (MEP), -propyl (MPRP), K-butyl (MBP), K-pentyl (MPEP), and -octyl (MOP) phthalates is compared. The phthalic acid monoesters are arranged in Figure 2.40 in the order of increasing number of carbons in the alkyl chain, which in turn is roughly correlated with an increase in hydrophobicity. 

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