Concentration distribution ratio

The partitioning of the potassium ion between the resin and solution phases is described by the concentration distribution ratio, D ... 

The foregoing equation reveals that essentially the concentration distribution ratio for trace concentrations of an exchanging ion is independent of the respective solution of that ion and that the uptake of each trace ion by the resin is directly proportional to its solution concentration. However, the... 

Concentration distribution ratio.. Ratio of the analytical concentration of a component in the stationary phase to its analytical concentration in the mobile phase. 

IUPAC recommendations for defining D are [7] distribution coefficient, D the ratio of the total (analytical) amount of a solute per gram of dry ion exchanger to its analytical concentration (total amount per cm ) in the solution concentration distribution ratio, D the ratio of the total (analytical) concentration of a solute in the ion exchanger to its concentration in the external solution (dimensionless) the concentrations are calculated per cm of the swollen ion exchanger and cm of the external solution volume distribution coefficient, D, the ratio of the total (analytical) concentration of a solute in the ion exchanger calculated per cm of the column or bed volume to its concentration (total amount per cm ) in the external solution. 

A ratio expressing the total concentration of solute in one phase relative to a second phase all forms of the solute are considered in defining the distribution ratio (D). 

In evaluating the efficiency of an extraction, however, we must consider the solute s total concentration in each phase. We define the distribution ratio, D, to be the ratio of the solute s total concentration in each phase. 

If the ligand s concentration is much greater than the metal ion s concentration, the distribution ratio is given as ... 

The problem with a simple extraction is that the separation only occurs in one direction. In a liquid-liquid extraction, for example, we extract a solute from its initial phase into the extracting phase. Consider, again, the separation of an analyte and a matrix interferent with distribution ratios of 5 and 0.5, respectively. A single liquid-liquid extraction transfers 83% of the analyte and 33% of the interferent to the extracting phase (Figure 12.1). If the concentrations of A and I in the sample were identical, then their concentration ratio in the extracting phase after one extraction is... 

The physical process of Hquid—Hquid extraction separates a dissolved component from its solvent by transfer to a second solvent, immiscible with the first but having a higher affinity for the transferred component. The latter is sometimes called the consolute component. Liquid—Hquid extraction can purify a consolute component with respect to dissolved components which are not soluble in the second solvent, and often the extract solution contains a higher concentration of the consolute component than the initial solution. In the process of fractional extraction, two or more consolute components can be extracted and also separated if these have different distribution ratios between the two solvents. 

Impurities present in the organic phase may sometimes be removed by backwashing. The organic extract when shaken with one or more small portions of a fresh aqueous phase containing the optimum reagent concentration and of correct pH will result in the redistribution of the impurities in favour of the aqueous phase, since their distribution ratios are low most of the desired element will remain in the organic layer. 

Distribution Ratio (DR) The DR relates the concentration of an amine present in the steam phase to that concentration in the condensate phase (vapor-liquid distribution ratio). Consequently, it identifies in which condensate production region of a steam-condensate system any particular amine will concentrate and thus provide protection against corrosion. It also helps to indicates the portion of amine loss due to vaporization in a condenser or venting of a deaerator. The expression for DR is shown here ... 

The early field studies revealed that elevated concentrations of fallout plutonium correlated with Increased concentrations of dissolved organic carbon. Experiments at Argonne National Laboratory corroborate this correlation the explanation Is probably that the organic compounds complex Pu(IV), and, hence, decrease the distribution ratio between water and sedlments(27). In these experiments the distribution ratio (Kj) between sediment and natural waters was measured as a function of DOC. Measurements of Kj In both field and laboratory experiments show an unmistakable effect of DOC upon the distribution ratio. Figure 4 shows the Inverse correlation between the K, of plutonium and concentration of DOC. 

Fission Product Extraction. Tables IV and V list the distribution ratios for most of the fission products produced in spent fuel. Also included are corrosion products Cr, Fe, and Ni. Extractant concentrations for DHDECMP, HHDECMP, and 0c >D[IB]CMP0 were selected on the basis of data in Figure 2. The aqueous acidity... 

Conceptual Flowsheet for the Extraction of Actinides from HLLW. Figure 5 shows a conceptual flowsheet for the extraction of all the actinides (U, Np, Pu, Am, and Cm) from HLLW using 0.4 M 0< >D[IB]CMP0 in DEB. The CMPO compound was selected for this process because of the high D m values attainable with a small concentration of extractant and because of the absence of macro-concentrations of uranyl ion. Distribution ratios relevant to the flowsheet are shown in previous tables, IV, V, VI, and VII and figures 1 and 2. One of the key features of the flowsheet is that plutonium is extracted from the feed solution and stripped from the organic phase without the addition of any nitric acid or use of ferrous sulfamate. However, oxalic acid is added to complex Zr and Mo (see Table IV). The presence of oxalic acid reduces any Np(VI) to Np(IV) (15). The presence of ferrous ion, which is... 

Calculated O radical concentration distributions for total spark energy of 0.7mJ. (a) Ratio of capacity spark energy 20%. (b) Ratio of capacity spark energy 80%. 

Under transient conditions the concentration distribution depends not only on the coordinate but also on time. The relevant functions can be found by considering the linear diffusion occurring along the x-axis in a volume element (iU bounded by the two planes S which are a distance dx apart (Fig. 11.1) it is obvious that dV=S dx. The rate of concentration change dcj/dt in this volume is given by the ratio of -S dJj (the... 

The concentration distributions found at different times after the start of current flow are shown in Fig. 11.4. It is a typical feature of the solution obtained that the variable parameters x and t do not appear independently but always as the ratio Like Eq. 11.15), this indicates that the diffusion front advances in proportion to the square root of time. This behavior arises because as the diffusion front advances toward the bulk solution, the concentration gradients become flatter and thus diflusion slows down. 

The above relationship shows that a high distribution ratio can be achieved by maintaining a high nitrate ion and TBP concentrations. The process based on TBP is outlined in Figure 5.33. 

The distribution ratio D is used only in the context of ionizable molecules [229,270-276]. Otherwise, D and P are the same. The partition coefficient P, defined in Eq. (4.2), refers to the concentration ratio of a single species. In contrast,... 

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