Solvent strip

Inversion ofMon cjueous Polymers. Many polymers such as polyurethanes, polyesters, polypropylene, epoxy resins (qv), and siHcones that cannot be made via emulsion polymerization are converted into latices. Such polymers are dissolved in solvent and inverted via emulsification, foUowed by solvent stripping (80). SoHd polymers are milled with long-chain fatty acids and diluted in weak alkaH solutions until dispersion occurs (81). Such latices usually have lower polymer concentrations after the solvent has been removed. For commercial uses the latex soHds are increased by techniques such as creaming. 

Density Difference Between Particle and Liquid. Separation cannot take place if A6 = 0. Some mineral oils have the same density as water at room temperature. If it is heated to 80°C, the reduction of the density of water is less than that of the mineral oil, resulting ia the water becoming heavier. Therefore separation is possible. Dilution of a Hquid by a solvent, eg, molasses by water or heavy oil by naphtha, results ia lower density and lower viscosity of the Hquid. Solvent stripping takes place at a later stage. 

Recovery of the solvent, sometimes by chemical means but more often by distillation, is almost always required, and the recoveiy system ordinarily is considered an integral part of the absorption-system process design. A more efficient solvent-stripping operation normally will result in a less costly absorber because of a smaller concentration of residual dissolved solute in the regenerated solvent however, this may increase the overall cost of solvent recoveiy. A more detailed discussion of these and other economic considerations is presented later in this section. 

No solvent-stripping or recovery process is required, and product contamination by solvent or solvent impurities is avoided. The chemical reaction may take place in the melt... 

The mass spectra of mixtures are often too complex to be interpreted unambiguously, thus favouring the separation of the components of mixtures before examination by mass spectrometry. Nevertheless, direct polymer/additive mixture analysis has been reported [22,23], which is greatly aided by tandem MS. Coupling of mass spectrometry and a flowing liquid stream involves vaporisation and solvent stripping before introduction of the solute into an ion source for gas-phase ionisation (Section 1.33.2). Widespread LC-MS interfaces are thermospray (TSP), continuous-flow fast atom bombardment (CF-FAB), electrospray (ESP), etc. Also, supercritical fluids have been linked to mass spectrometry (SFE-MS, SFC-MS). A mass spectrometer may have more than one inlet (total inlet systems). 

Film Formation. A novel feature of these Au-organic solvent colloids is their film forming properties that can be induced simply by solvent stripping. In this sense they are "living" colloidal particles. Films formed in this way are conductive, but less so than pure metals. (in ) The higher resistance of the films is due to the incorporation of substantial portions of the organic solvent, which can partially be removed by heating, and resistivity then decreases.(M1)... 

The disadvantages of sulfur dioxide are its high vapor pressure and its low solvent power under normal operating conditions. Fortification of sulfur dioxide with benzene to increase solvent power has been successful in some applications (4). On the other hand, the high volatility of sulfur dioxide results in easy solvent stripping, and its low viscosity aids rapid settling. 

Behavior of Viscous Polymers during Solvent Stripping or Reaction in an Agitated Thin Film... 

To characterize heat transfer of solvent stripping processes in the Luwa high-viscosity machine, two different heat transfer coefficients have been defined ... 

Significant impact on the environment and generation of wastes (mainly associated with the less than 100% selectivity in the reduction and oxidation steps - formation ofhydroxyanthrones, anthrones, anthracenes, and epoxide, some solvent stripping by air used in the oxidation step, and in the crude H202 stream). 

L. A. S. Gorman and J. S. Dordick, Organic solvents strip water off enzymes, Biotechnol. Bioeng. 1992, 39, 392-397. 

II). trans-m-Bromocinnamic acid (14.8 g), ethanol (173 ml) and concentrated sulfuric acid (0.4 ml) were combined and heated at reflux for 15 hours. About 150 ml of the ethanol was distilled off, and the remaining solution was poured into ice/water (140 ml). The cold mixture was made strongly alkaline with 40% sodium hydroxide and extracted with methylene chloride (4x60 ml). The combined methylene chloride extract was dried over anhydrous potassium carbonate. The potassium carbonate was removed by filtration and the solvent stripped off under reduced pressure. trans-ethyl-3-Bromocinnamate, was obtained as a partially solidified oil. (IR spectrum was consistent with this compound). 

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