Effect on separation factor

Other system variables that will have an effect on the separation process are temperature and relative humidity of the gas. Increasing the temperature raises most permeabilities by about 10 to 15% per 10°C and has little effect on separation factors. The effect of relative humidity is variable depending upon the membrane used. High relative humidities, greater than 95%, are generally detrimental due to membrane plasticization. Contamination with liquid water has been found to dramatically reduce membrane performance for cellulose acetate ... 

Separation factors. Deuterium separation factors in the electrolytic plants described above, together with the types of cells used and operating conditions that may have had an effect on separation factor, are listed in Table 13.13. Separation factors of from 6 to 10 have been reported for the secondary plants, and from 3.8 to 7.0 for the primary plants. The lower values for the primary plants are attributed to their higher cell temperatures, their use of diaphragms, and the greater difficulty of keeping large equipment clean. 

Increasing the temperature raises most permeabilities by about 10 to 15% per I0°C and has little effect on separation factors (Schell and Hoemschemeyer, 1982). 

FIGURE 1.5 pH -effect on retention factors k and separation factors a. CSP 0-9- tert-butylcarbamoyl)quinine bonded to sihca column dimension, 150 x 4 mm ID eluent, methanol-ammonium acetate buffer (80 20, v/v) (adjusted with acetic acid) temperature, 25°C 1 mL min sample, N-benzoyl-leucine (Bz-Leu). (Reproduced from M. Lammerhofer et al., American Laboratory, 30 71 (1998). With permission.)... 

The discussion of IL-based stationary phases up to this point has centered around ILs that are either coated as a thin film on a capillary wall or on a solid support. Although ILs exhibit a variety of properties that allow them to be unique stationary phases, their most significant drawback lies with their drop in viscosity with increasing temperature. This results in an increased propensity for flowing of the IL within the capillary, which often produces pooling of the stationary phase and nonuniform film thickness throughout the column. These factors often contribute to diminished analyte retention time reproducibility as well as detrimental effects on separation efficiency. 

A K-factor correlation based on a convergence pressure of 5000 psia can be used in separator calculations for all of these reservoir systems. Surface separators for black oils typically operate at low pressures. Convergence pressure has little effect on K-factors at low pressure. 

Changes in solvation pattern on activation, and the effect on A factors for reactions involving charges and charge-separated species in solution... 

Capillary electrochromatography is a more complicated system than CE and HPLC due to the combination of both electrophoretic and chromatographic transport mechanisms. It is difficult to define an effective selectivity (separation factor) as in the case of general chromatography or general electrophoresis. To better illustrate the interactions that control selectivity, we defined a relative selectivity a,. =. tjt 2), and postulated a model that illustrates the effect of separation parameters on the enantioselectivity [10]. 

The Effect of Different Counter lons on Separation Factor... 

Figure 4.13 Effects of the relative amount of solvent on separation factor. From Ref. [85] with permission.

Figure 4.15 Effect of internal acid concentration on separation factors of Cu(II) and Ni(II) ions. From Ref. [84] with permission.

Table 13.6 Effect of deuterium content on separation factor in distillation of ammonia...

The number of theoretical stages is first determined by well-known shortcut methods and then by a multicomponent simulation of the separation process. Both parts can and will be used for analyzing the separation process with respect to the effect of separation factor, reflux ratio (the amount of top product reintroduced to the separation), degree of separation etc. on the number of theoretical stages. There, computational methods provide insight into the separation process without actually carrying out the separation. 

Table 21.1.4. The effect of entrainers on separation factor (Adapted from Brunnei )...

Figure 13.8-1. Effects of separation factor and pressure ratio on permeate purity. (Feed Xf = 0.30.) [From Membranes Separate Gases Selectively, by D. J. Stookey, C. J. Patton, and G. L. Malcolm, Chem. Eng. Progr., 82(11), 36 (1986). Reproduced by permission of the American Institute of Chemical Engineers,... 

The character of the diluent in a solvent extraction separation scheme generally can have a profound effect on the overall degree of extraction, but the effect of diluent on separation factors is usually much more subtle. Alteration of the diluent modifies metal-ion extraction equilibria primarily by its effect on the solvation of the hydro-phobic metal complex. Although few recent studies have been made of diluent effects in lanthanide/actinide separation (with no truly systematic investigations), enough historical reports exist to make some general observations of the effect of diluent on lanthanide/actinide separation. 

The effect of the surfaee porosity on separation factors for H2/CO for porous substrates and RM composite membranes is shown in Fig. 11.2. 

However, the separation characteristics of membrane interfaces do not depend solely on the physical form of surface features. In liquids, surface electrical properties and the adhesion of solutes to membrane surfaces may also have profound effects on separation performance. It is thus exceedingly fortunate that an atomic force microscope may also be used to determine both of these additional controlling factors. Finally, means may be devised to quantify all of these controlling factors in liquid environments that match those of process streams. 

Hertzian, M. H. Kirsanov, H.C. and Gordon, G.M. Effect of Separate Factors on Efficiency of Tapping of a Dust in Percussion Scrubbers. Works of Institute of Non-Ferrous Metals 1975,55, 112-117. 

The volume between the solvent mixing point and column inlet is defined as dwell volume, and the corresponding time it takes for the selected composition of mobile phase to reach the column is called dwell time. Although the dwell volume is not the part of the extra-column volume, it is discussed in this section, as it impacts chromatographic performance. Under gradient conditions, the dwell volume for an HPLC system can have a significant effect on separation parameters including retention times (tr) and apparent retention factors fc. ... 

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