Pressure effect, methyl ethyl ketone

There seems to be special promise in oxidizing liquefied hydrocarbon gases at temperatures and pressures approximating critical levels. That such reactions are highly effective is attested, for example, by the liquid-phase oxidation of butane, one of the simplest and most efficient methods of producing acetic acid and methyl ethyl ketone. 

The effect of solvents on the oxidation route as regards the composition of reaction products was investigated for methyl ethyl ketone at 145° to 160°C. at a pressure of 50 atm. (9, 10). The composition of products under these conditions is a function of the competition between two routes of the peroxy radical reactions ... 

G2. Pressure can have a large effect on the equilibrium data for nonideal systems. Your cortpany plans to process a mixture of acetone, methyl ethyl ketone, and methyl isobutyl ketone in an ordinary, single-feed distillation column with a total condenser and a partial reboiler. Feed flow rate is 200 kmol/h feed mole fractions acetone = 0.25 methyl ethyl ketone = 0.45 and methyl isobutyl ketone = 0.3. Feed can be made available at any desired pressure. Feed tenperature is 75°C, D = 50 kmol/h, and adiabatic column. The purpose is to produce pure acetone. 

The solvents recommended for ABS are methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, and methylene chloride. The solvent used should be quick drying to prevent moisture absorption yet slow enough to allow assembly of the parts. The recommended cure time is 12 to 24 hr at room temperature. The time can be reduced by curing at 55 to 65°C. A cement can be made by dissolving ABS resin in solvent up to 25 percent solids. This type of cement is very effective in joining parts that have irregular surfaces or areas that are not readily accessible. Because of the rapid softening actions of the solvent, the pressure and amount of solvent applied should be minimal. 

The radiation-initiated polymerization of vinylidene fiuoride is used on a laboratory scale only. The effect of polymerization conditions on the chain defects, content, and changes in the crystalline phases have been studied [528,536,537,544]. Doll and Lando [544] used a °Co source with an average dose rate of 0.33 Mrad/h. The polymerization was carried out between 0 and 400 °C at a pressure equal to the vapor pressure of the solvent-vinylidene fluoride mixture. Esters and ketones (acetone, methyl ethyl ketone, ethyl acetate, acetophenone), DMF, DMSO, and y-butyrolactone were used as solvents. All these solvents are good chain-transfer agents for vinylidene fluoride. The molding characteristics of the resulting polymers were very poor and the intrinsic viscosity of the sample polymerized in acetone solution was low (0.183 dL/g) compared to that of a suspension-polymerized polymer (1.68 dL/g) [544]. 

The effect of temperature on the yield of the main groups of butane oxidation products is shown in Fig. 10.15. The yield of oxygenates is promoted by a temperature reduction, whereas temperature rise increases the yield of olefins, first primary and then lower ones [248]. It is interesting that the composition of the gas-phase butane oxidation products is strikingly different from that of the liquid-phase oxidation products obtained at high pressure, when mainly acetic acid and methyl ethyl ketone are produced, with alcohols being present in small amounts [249]. 

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