METHYLETHYLKETONE

Oil content (waxes) NFT 60-120 ISO 2908 ASTM D 721 Soluble portion in methylethylketone at -32°C... 

In another case an unlabeled drum smelled like methylethylketone (MEK), so it was assumed to be MEK and was fed to the plant. Actually, it contained ethanol and a bit of MEK. Fortunately, the only result was a ruined batch. 

Acetone Carbon tetrachloride, chloroform/o-chlorophenol, chloroform// -cresol, chloroform/hexafluoroisopropanol, chloroform/methanol (up to 60%), o-dichlorobenzene, dimethylformamide, dimethyl sulfoxide, dioxane, ethylacetate, FC-113, haxane, methylethylketone, N-methylpyrrolidone, pyridine, quinoline, cyclohexane, dodecane... 

The main disadvantage of precipitation with a polar (water-soluble) solvent is the need for a costly distillation stage to recover the relatively laige volumes of solvent used. Another disadvantage is the precipitation of proteins, salts and, in some cases, pigments which reduces the purity and leads to discoloration of the product. To overcome these problems, precipitation using less polar solvents, such as methylethylketone, has been proposed. Only 23% (w/v) methylethylketone is sufficient to saturate the aqueous phase and precipitate exopolysaccharides quantitatively. 

MethyloU2-Butanol (2-Methyl-l,3-butanediol or a >Dioxy-/3-methylbutane). CH3.CH(OH).CH(CH2OH).CH3 mw 104.15, viscous oil, bp 200° 98—99° at 9mm. Sol in w, v sol in ale and eth. Can be prepd either by reduction of the corresponding aldehyde, 2-methylbutanol(3)-al-(l) with A1 amalgam (Ref 1), or by electrolytic reduction in 10% sulfuric acid of the corresponding ketone ale. In the latter case, methyl-2-butanone-3-ol-(l), obtained by the condensation of methylethylketone with formaldehyde, can be used. On nitration, it yields an expl dinitrate Refs 1) Beil 1,482,(250) 2)L.P.Kyria-kides, JACS 36, 535(1914)... 

Fig. 21. Liquid-liquid phase behavior in the system methylethylketone-water [from Timmermans (T3)].

In Figure 3 the merits of the two processes for p-xylene oxidation are compared. The main disadvantages of the Eastman Kodak/Toray cooxidation method are the need for a cosubstrate (acetaldehyde of methylethylketone) with concomitant formation of a coproduct (0.21 ton of acetic acid per ton product) and high catalyst concentration. The Amoco MC process, on the other hand, has no coproduct and much lower catalyst concentrations but has the disadvantage that the bromide-containing reaction mixture is highly corrosive, necessitating the use of a titanium-lined reactor. 

Dissolution/reprecipitation processes were evaluated for the recycling of poly-epsilon-caprolactam (PA6) and polyhexamethyleneadipamide (PA66). The process involved solution of the polyamide in an appropriate solvent, precipitation by the addition of a non-solvent, and recovery of the polymer by washing and drying. Dimethylsulphoxide was used as the solvent for PA6, and formic acid for PA66, and methylethylketone was used as the non-solvent for both polymers. The recycled polymers were evaluated by determination of molecular weight, crystallinity and grain size. Excellent recoveries were achieved, with no deterioration in the polymer properties. 33 refs. 

In an industrial application dissolution/reprecipitation technology is used to separate and recover nylon from carpet waste [636]. Carpets are generally composed of three primary polymer components, namely polypropylene (backing), SBR latex (binding) and nylon (face fibres), and calcium carbonate filler. The process involves selective dissolution of nylon (typically constituting more than 50wt% of carpet polymer mass) with an 88 wt % liquid formic acid solution and recovery of nylon powder with scCC>2 antisolvent precipitation at high pressure. Papaspyrides and Kartalis [637] used dimethylsulfoxide as a solvent for PA6 and formic acid for PA6.6, and methylethylketone as the nonsolvent for both polymers. 

Plummer invented a process for the biodesulfurization of hydrocarbons [157], in which organic sulfur compounds contained in liquid hydrocarbons are converted to elemental sulfur. The reaction is carried out in the presence of a biocatalyst and hydrogen, by dissolving completely the liquid hydrocarbons in an organic solvent, such as a nucleophilic and/or electrophilic solvent(s). The nucleophilic solvent should have a pKa greater than 2, and the electrophilic solvent more negative than -2. Recommended nucleophilic solvents include -butylamine, diethylamine, butanediamine, ethylenimine, toluene, pyridine, aniline, and acetophenone. The electrophilic solvents could be methylethylketone, pyrrole, or benzaldehyde. 

The almost quantitative oxidation/complexation of palladium(O) in powder or foils by Me2dazdt 2I2 in THF, acetone, acetonitrile, and methylethylketone (MEK) to afford [Pd(Me2dazdt)2](I3)2 makes this synthetic route appealing for practical industrial applications. A selective process for Pd-recovery from model three-way car converters was simulated obtaining a Pd-extraction yield > 90%, and was proposed as an alternative to hydrometallurgical processes.62... 

Supported cationic rhodium(I) phosphine complexes, chiral at a men-thyl moiety, effected hydrogenation of ketones, but the 2-butanol produced from methylethylketone was optically inactive (348). Polystyrene-or silica gel-supported DIOP systems, however, are particularly effective for production of optically active alcohols (up to 60% ee) via asymmetric hydrosilylation of ketones (10, 284, 296, 366, 368 see also Section III, A,4). 

Therefore, in such systems an inhibitor may occur either in the free form or as a complex held together by hydrogen bonds. The hydrogen bonding between phenols and methylethylketone is characterized by the following equilibrium constants Kn parameters [46]. 

As the reaction temperature increases, the equilibrium constant diminishes, since complex formation is accompanied by heat liberation. Sterically hindered phenols form loose complexes because of the impeding effect of voluminous alkyl substituents in the ortho-position. Hydrogen bonding reduces the activity of phenols, which was first observed in the studies of the effects of cyclohexanol and butanol on the inhibitory activity of a-naphthol in cyclohexane [9]. This phenomenon was investigated in detail with reference to the oxidation of methylethylketone [10]. The k7 values for some inhibitors of the oxidation of ethylbenzene and methylethylketone are given below (333 K) [10,46] ... 

Another factor influencing the reactivities of polar particles is their nonspecific solvation. Since both the individual particles, namely phenol and peroxyl radicals and their complex are polar, rate constants must depend on the polarity of the medium, its permittivity s, in particular. This was confirmed in experiments with mixtures of benzene and methylethyl-ketone, which showed that kq diminishes as the concentration of methylethylketone decreases provided the hydrogen bonding between the benzene and methylethylketone molecules are taken into account [10]. The dependence of ogkq on the medium permittivity s is described by the formula... 

Let us now examine a simple numerical model for the mixing of substituent orbitals into the spectroscopic orbitals of the carbonyl chromophore. For this purpose we consider the triplet 3n— Tt excited state of the model amine derivative of methylethylketone shown in Fig. 3.75. 

P.Y.173, an isoindolinone pigment, affords somewhat dull, greenish yellow shades. It shows average fastness to organic solvents, especially to alcohols (ethanol), esters (ethyl acetate), and ketones (including methylethylketone and cyclohexanone). Its solvent resistance equals step 3 on the 5 step scale. P.Y.173 is almost completely to completely fast to mineral spirits and xylene. 

P.Y.182, which has been available for some years, provides somewhat reddish shades of yellow and is tinctorially strong. It is sensitive to a variety of organic solvents, especially to ketones such as methylethylketone and cyclohexanone, as well as to aromatic solvents such as toluene or xylene. In this respect, the pigment equals step 2 on the 5-step scale (Sec. 1.6.2.1). P.Y.182 is targeted for the paint and the plastics industry. 

The method described serves for the preparation of various 5-substituted or 5,5-disubstituted hydantoins, using appropriate cyanohydrins. With methylethylketone cyanohydrin there was obtained a 75 per cent yield of 5-methyl-5-ethylhydantoin, m.p. i4i-5°-... 

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