System methyl ethyl ketone

Eigure 2 iHustrates the situation for the system methyl ethyl ketone (MEIQ, methyl isopropyl ketone (MIPK), and water, and the problem of recovering a pure MIPK product from such mixtures. The bow-tie approximation of reachable compositions for several feeds is shown in Eigure 2a the exact reachable compositions are shown in Eigure 2b. 

Figure 12.17 Fugacities /, and f2 for the system methyl ethyl ketone(l)/toluene(2) at 50°C. dashed lines represent the Lewis/Randall rule.

To perform simulations with the model, the system methyl ethyl ketone (MEK)/polystyrene was used as a model system. The effect of the polymer molecular weight on the dissolution mechanism vm investigated. Figure 5 shows the solvent concentration profile in the polymer (Mn = 52,000) as a function of normalized position based on the undeformed coordinate system. The center of the slab is at =... 

Fig. 1 TLC and visible absorption spectra of synthetic colors extracted from a pickled vegetable under TLC/scanning densitometry. (A) Standards of tartrazine (Y-4), orange I (Or-I), and orange RN (Or-RN). (B) Standard of orange H (Or-II). (C) Extract of the sample. TLC/scanning densitometric conditions. Plate RP-18 (E. Merck). Solvent system methyl ethyl ketone-methanol-5 % sodium sulfate (1 1 1). Apparatus Shimadzu CS-9000. Wavelength scanning range 370 700 nm. Slit size 0.4 X 0.4 mm. Measuring mode reflecting absorption.

In relatively few instances the azeotropic composition lies outside the limits of solubility, as in the systems methyl ethyl ketone-water and phenol-water. In others, especially when the components have a very large difference in their boiling points, no azeotrope can form, as for ammonia-toluene and carbon dioxide-water. 

Kurmanadharao, K. V. Rao, C. V. Binary vapour-liquid equilibria of the systems methyl ethyl ketone -cyclohexane and actone - cyclohexane. Chem. Eng. Sci. 1957, 7, 97-101. 

Cool Flames. An intriguing phenomenon known as "cool" flames or oscillations appears to be intimately associated with NTC relationships. A cool flame occurs in static systems at certain compositions of hydrocarbon and oxygen mixtures over certain ranges of temperature and pressure. After an induction period of a few minutes, a pale blue flame may propagate slowly outward from the center of the reaction vessel. Depending on conditions, several such flames may be seen in succession. As many as five have been reported for propane (75) and for methyl ethyl ketone (76) six have been reported for butane (77). As many as 10 cool flames have been reported for some alkanes (60). The relationships of cool flames to other VPO domains are depicted in Figure 6. 

Fig. 2. Methyl ethyl ketone (MEK)—methyl isopropyl ketone (MIPK)—water system where A1 and A2 represent two different a2eotropes FI, F2, and F3, different feed compositions and Y)n the corresponding bottoms and distillates, respectively (—), the distillation boundary and (B), the reachable compositions for the various feeds (a) approximate bow-tie and (b) exact reachable compositions.

More frequently either methyl ethyl ketone peroxide or cyclohexanone peroxide is used for room temperature curing in conjunction with a cobalt compound such as a naphthenate, octoate or other organic solvent-soluble soap. The peroxides (strictly speaking polymerisation initiators) are referred to as catalysts and the cobalt compound as an accelerator . Other curing systems have been devised but are seldom used. 

Solvents acetone, methyl ethyl ketone (MEK), toluene, xylene, glycol, ethers, alcohol defats and dries skin some may be absorbed may carry other components through skin high volatility, exposure possible irritation central nervous system depression (e.g. dizziness, loss of coordination) low to high toxicity, longterm effects... 

Toxicity. Breathing moderate amounts of methyl ethyl ketone (MEK) for short periods of time can cause adverse effects on the nervous system ranging from headaches, dizziness, nausea, and numbness in the fingers and toes to unconsciousness. Its vapors are irritating to the skin, eyes, nose, and throat and can damage the eyes. Repeated exposure to moderate to high amounts may cause liver and kidney effects. 

SO as to end the air mixture to adsorber No. 2. The system is then fully automatic. Solvents which have been successfully recovered by the activated carbon adsorption method include methanol, ethanol, butanol, chlorinated hydrocarbons including perchlorethylene, which boils at 121 C (250 °F), ethyl ether, isopropyl ether, the acetates up to amyl acetate, benzene, toluene, xylene, mineral spirits, naphtha, gasoline, acetone, methyl ethyl ketone, hexane, carbon disulfide, and others. 

For a number of applications curing at room temperature is desirable. This so-called cold cure is brought about by using a peroxy initiator in conjunction with some kind of activator substance. The peroxy compounds in these cases are substances such as methyl ethyl ketone peroxide and cyclohexanone peroxide, which as used in commercial systems tend not to be particularly pure, but instead are usually mixtures of peroxides and hydroperoxides corresponding in composition approximately to that of the respective nominal compounds. Activators are generally salts of metals capable of undergoing oxidation/reduction reactions very readily. A typical salt for this purpose is cobalt naphthenate, which undergoes the kind of reactions illustrated in Reactions 4.6 and 4.7. 

Maiti and Bhowmick also investigated the diffusion and sorption of methyl ethyl ketone (MEK) and tetrahydrofuran (THE) through fluoroelastomer-clay nanocomposites in the range of 30°C-60°C by swelling experiments [98]. A representative sorption-plot (i.e., mass uptake versus square root of time, at 45°C for all the nanocomposite systems is given in Figure 2.12. 

The results of intrinsic viscosity measurements for four polymer-solvent systems made at the -temperature of each are shown in Fig. 141. The four systems and their -temperatures are polyisobutylene in benzene at 24°C, polystyrene in cyclohexane at 34°C, poly-(di-methylsiloxane) in methyl ethyl ketone at 20°C, and cellulose tricapry-late in 7-phenylpropyl alcohol at 48°C. In each case a series of poly-... 

It will be observed that entropies of dilution (as indicated by i) are highly variable from one system to another. This is contrary to the theory developed from consideration of lattice arrangements, according to which pi should be approximately 1/2 and nearly independent of the system. For polystyrene in methyl ethyl ketone, the entropy of dilution is nearly zero i.e., this solvent is a poor one not because of an adverse energy of interaction but because of the low entropy. First neighbor interactions apparently contribute to the entropy as well as to the energy, a point which was emphasized in Chapter XII. It will be noted also that cyclic solvents almost without exception are more favorable from the standpoint of the entropy than acyclic ones. 

The butyl alcohol is pumped from storage to a steam-heated preheater and then to a vaporiser heated by the reaction products. The vapour leaving the vaporiser is heated to its reaction temperature by flue gases which have previously been used as reactor heating medium. The superheated butyl alcohol is fed to the reaction system at 400°C to 500°C where 90 per cent is converted on a zinc oxide-brass catalyst to methyl ethyl ketone, hydrogen and other reaction products. The reaction products may be treated in one of the following ways ... 

The above values are applicable only in the limiting case of infinite dilution. The interaction parameter varies with the volume fraction of polymer network as has been demonstrated for the PDMS-benzene system by Flory (47) and PDMS-methyl ethyl ketone, PDMS-methyl isobutyl ketone, PDMS-ethyl-n-butyl ketone, and PDMS-diisobutyl ketone by Shiomi et al. (48). Theoretically calculated and experimentally observed values of X as a function of volume fraction of polymer are given for PDMS in alkanes, aromatic hydrocarbons, and dimethyl siloxane oligomers by Gottlieb and Herskowitz (49). In the case of PDMS-alkanes, x was practically independent of the volume fraction of polymer. 

MEK-MIPK-water distillation system, 22 304-305, 306, 307 MEKPs (methyl ethyl ketone peroxides), 78 489... 

Methyl ethyl ether, 10 567 Methyl ethyl ketazine (MEK), 13 582, 583 Methyl ethyl ketone (MEK), 13 700 14 581 adipic acid solubility, l 555t azeotrope with methanol, 8 801 in MEK—MIPK—water system, 22 304-305, 306, 307 peroxide, 14 292... 

Altenkirch H, Wagner HM, Stoltenburg G, et al. 1982. Nervous system responses of rats to subchronic inhalation of n-hexane and n-hexane + methyl-ethyl-ketone mixture. J Neurol Sci 57 209-219. 

PMMA) film is quenched by permeation of methyl ethyl ketone (MEK), a good solvent for PMMA. A steady-state MEK concentration profile has been estimated from quenching data with existing sorption and light scattering data. The profile contains all the features of Case II diffusion the Fickian precursor, the solvent front, and the plateau region. However, the solvent front is not so steep as those observed in systems where penetrant diffusion is much slower. 

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