Volatility of solvents

Cho HJ, Jaffe PR, Smith JA. 1993. Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments. Water Resour Res 29 3329-3342. 

The multicomponent mobile phase must not be used repeatedly because the volatility of solvents produces a continuous modification of the solvent ratio, which negatively affects the chromatographic results. 

Volatilization of solvent components can become a problem when the system is operated at elevated temperatures or in hot climates. The human toxicity of solvent components is a generally unknown factor and could be a problem in a system enclosed in a building. 

Toxicity/symptoms nervous system, reproductive system, and death General facts long history of use (alcohol), high volatility of solvents results in inhalation exposure to vapors... 

Extractive Distillation Recovery of Isoprene. A typical flowsketch and material balance of distillation and solvent recovery towers for extracting isoprene from a mixture of cracked products with aqueous acetonitrile appears in Figure 13.26. A description of the flowsheet of a complete plant is given in Example 2.10. In spite of the fact that several trays for washing by reflux are provided, some volatilization of solvent still occurs so that the complete plant... 

Each solvent investigated is quantified in the same manner using their respective calibration curve and formula. Because an absolute calibration is used, sample analysis and calibration must be performed on the same day. Standards more than one day old should be scrutinized for variations in concentration due to volatilization of solvent from the carbon disulfide into the head space. 

Olabisi, O., "Volatility of Solvents from Polysulfone Melt," J. Appl. Polym. Sci., 22, 1021 (1978). 

As described in earlier chapters, the volatility of solvents is of crucial important in their applications. In 2007, the groups of Liotta, Eckert and Jessop first reported on the formation and use of piperylene sulfone (PS) as a recyclable alternative to dimethyl sulfoxide (DMSO) (Figure 9.11). DMSO, in addition to dimethylformamide (DMF) and hexamethylphosphoramide (HMPA), is a widely used dipolar, aprotic solvent. However, it is difficult to remove from products by distillation and is rarely recycled. In contrast, PS decomposes cleanly at temperatures above 100°C to give ra -l,3-pentadiene and sulfur dioxide, which reform PS at room temperature (Figure 9.11). 

Bognitzki et al. examined the relationship between the volatility of solvents used and the pore structure of fibers. They inferred that the solidification of fibers is controlled by onset of glass transition or by onset of crystallization (Bognitzki et al. 2001). Tetrahydrofuran MacDiarmid et al. have electrospun... 

One way to estimate the volatility of solvents at room temperature is to saturate pieces of filter paper with solvent, and time how long it takes for all the solvent to evaporate. Alternatively, the boiling point of a solvent may be taken as a rough indication of its volatility. One of the most volatile solvents available in the laboratory is ethoxyethane (diethyl ether), with a normal boiling point of 34.5°C (see Box 10.3). 

The electrodeposition which is commercially most important is that of A1 by the NBS process . The plating bath is a mixed electrolyte solution of LiAlH. (0.2-O.4 M) and AICI3 (3 M) in anhydrous DEE. Attempts have been made to reduce the volatility of solvent (flammability), to improve the operating life of the bath, to increase the current density, and to find substitutes for LiAlH. ... 

The internal stresses in adhesive-bonded joints arise for two reasons. In the course of setting of the adhesive, its volmne decreases due to volatilization of solvents, polymerization or physical structurization. As a result of the adhesion interaction of the adhesive and the substrate, the film can contract only in thickness, which is why stresses that appear in it are parallel to the siuface. The film extends while contraction stresses appear in the substrates. Rapid growth of stresses, which tend to reduce the length of the film, begins from the moment the polymer loses yield. 

The high volatility of solvents, e. g., VOCs and the fast biotransformation rate (in the environment and within the human body) for most of the solvents. 

Differences in the volatility of solvents with similar molecular weights will thus be a reflection of the strength of their intermolecular forces. This is highlighted by solvents in Table 2.4 which have been ranked according to increasing boiling point, indicative of stronger molecular interactions. 

Expression of evaporation tendency. The more volatile a liquid, the lower its boiling point and the greater its flammability. The volatility of solvents can be precisely determined by tests for evaporation rate also, it can be estimated by tests for flash point and vapor pressure, and by distillation tests. 

When choosing an optimum mobile phase composition, along with the search for the best selectivity value, a number of considerations should be kept in mind. These include parameters such as solvent viscosity, sample solubility in the mobile phase, pH, volatility of solvents/ buffers, solvents cost, and safety hazards. 

Daniels et al. (1986) and Du et al. (1995) found that striation is reduced when spincoating is conduced in a closed chamber or in an atmosphere filled with solvent vapor. Therefore, solvents of low volatility are expected to suppress the formation of striations. In order to study the effect of the volatility of solvents on the formation of striations, spincoating films were prepared from TEOS solutions containing various alcohols (Kozuka, 2004c). 

Photometric detection, 208-210 Photomultipliers, 378-379 Physical methods of detection, 206-211 photometric detection, 208-210 visual detection, 206-208 Physical phenomena in TLC, 49-53 broadening of chromatographic spots, 50-53 capillary flow, 49-50 volatility of solvents, 53 Pigments. See Natural pigments Planar chromatography (instrumental TLC), 3, 129-148,373-385 automation in, 131,382-384 chromatogram development, 135-140 automated multiple development (AMD), 138-140... 

Theoiy and mechanism] basic physical phenomena, 49-53 browning of chromatographic spots, 50-53 ciq>illa]y flow, 49-50 volatility of solvents, 53 measures of chromatographic system efficiency, 54-58... 

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