Solvent extraction data of

In the first step, the hydrolysis constant for Zr, (OH) formation was obtained by re-interpretation of a series of data (solvent extraction data of [75TRI/SCH] and heat capacity data of [76VAS/LYT]). The data of [75TRI/SCH] were re-evaluated (see Appendix A) in terms of Zr, (OH) formation. The authors of [75TRI/SCH] assumed ZrOH to be the dominant monomeric hydrolysis species in 4 m HCIO4. In contrast, the first hydrolysis constant, y ,, (see Section V.3.1.1.1) clearly indicates that Zr is the dominant species in the experimental solutions. The observed increase in polymer concentration, proportional to the third power of the monomeric Zr concentration, therefore, indicates trimer formation not with the composition Zr, (OH) (as invoked by [75TRI/SCH]) but of Zr, (OH) according to the reaction ... 

The calculated uncertainties in A(.G° /RT will increase with the uncertainty in the interaction parameters and with increasing ionic strength. We have used the studies of [1963ALL/MCD] and the solubility investigations of many sulphate solids (see Section IX.1.3.3) to explore this effect, because the chemical system is simple, with Th(S04)3 as the dominant species. The solvent extraction data of [1963ALL/MCD], where the ionic strength varies from a very low value up to 4.5 m, were used as a first test of the impact of uncertainties in interaction parameters on the fitted values of AfG° /RT (Th(S04)3 ), as it is expected that this system will provide maximum variability in the calculated values. The values of all of the ion-interaction parameters involved in this system ate Usted in Table D-1 and the AjG° /RT values of all of the species considered in interpretation ate hsted in Table D-2. The fitted AfG° /RT (Th(S04)3 ) value was found to be -(1209.511 +0.086) when maximum values of all the ion interaction parameters, based on the uncertainties reported in Table D-1, were used and -(1209.348 + 0.088) when the minimum values were used. These compare with the value of A G° /RT (Th(S04)3 ) = -(1209.432 + 0.086) found when the mean values of the ion interaction parameters were used (see Section IX. 1.3.2). 

From adsorption analysis data, it is possible to calculate theoretical yields of deoiled wax, asphalt, resins, and solvent extraction yields of waxy raffinate. Nearly 100 different stocks have been so evaluated by California Research Corp. during the past few years and many of these data have been correlated with operations in refinery equipment and with pilot plant operations. 

The intent of this article was to demonstrate, based on a wealth of relatively new experimental data, that there is sufficient analytical selectivity and sensitivity to accept polarimetry and CD as viable and easy-to-use analytical detection methods. In contrast to other detectors, they provide the capability of making direct analytical assays after a sample work-up that is a simple solvent extraction and of measuring enantiomeric purities in the ranges specified by the FDA for the pro-... 

The Am thiocyanates have been studied intensively because of the separation of lanthanide and actinide elements in thiocyanate media. Three complexes of general formula Am(SCN) n = 1-3) have been identified from spectroscopic and solvent extraction data. 

A new approach for the chemical removal of pyritic sulfur from coal is described. The process is based on the discovery that aqueous ferric salts selectively oxidize the pyritic sulfur in coal to chemical forms which can be removed by vaporiza-tion, steam, or solvent extraction. Data for removal of the pyritic sulfur from four major coals (Lower Kittanning, Illu nois No. 5, Herrin No. 6 and Pittsburgh) are presented together with a discussion of the process chemistry. The effect of variables, such as coal particle size, acid and iron concern tration, reaction time, and temperature are discussed. The results show that near complete removal of pyritic sulfur can be obtained under mild conditions, resulting in a reduction of the total sulfur content of the coals from 40 to 80%, depending on the original pyritic sulfur content. 

Since these latter reactions have been neglected in the analysis of the solvent extraction data, it is most probable that the hydrolysis constants have been overestimated. For example, employing the numerical technique used in the paper, the limit as [OH-] approaches zero for the first function Gi[OH-] is correctly written as ... 

One aspect of the present review that is different from earher voltrmes is that a fitting code incorporating the SIT model, NONLINT-SIT, has been used in some systems to optimise the values of /RT of the relevant sohd and aqueotts species and the SIT ion-interaction parameters, using all the experimental solubility, ion-exchange, and solvent extraction data. From these, the optimised values of the different quantities can be compared with the other reported values. Appendix D describes the modus operand of the NONLINT-SIT program, with an illustrative example. 

Thus the solvent extraction data at constant ionic strength can be interpreted by taking into account only the changing composition of the HCIO4-HX media. For the data from... 

Evaluation of TTA solvent extraction data for Th" in 4.0 M (H,Na)C104-(H,Na)Cl using alternatively the chloride complexation approach and the ion interaction approach with... 

Stock solutions are typically prepared on a weight percent (PEGs or salts), molar (salts), or molal (salts) concentration basis. Equal aliquots by volume of each stock solution are combined and mixed to yield an ABS. The total system composition can be calculated and the phase compositions taken from the appropriate phase diagram and tie line data. This method of reporting allows the results to be more readily compared with solvent extraction data. 

Partition or liquid-liquid chromatography is similar to solvent extraction. In fact, solvent-extraction data can be used to predict partition coefficients for LLC. The resolving power and speed of LLC are considerably greater than that of solvent extraction, however, since the equivalent of several thousand partitions takes place as the sample components move down a column. LLC is generally better suited to analytically separating complex mixtures, whereas extraction is used more for large-scale preparative separations or for separating relatively simple mixtures. 

A very great deal of research on liquid-liquid extraction systems for Pu has been carried out in the development of large-scale processes, and a large portion of the solvent extraction data reported in this section was taken under the spur of the seemingly never-ending quest for more specific extractants, better radiation stability, and the like. The basic data on the extractive properties of a given solvent are, of course, equally applicable in the laboratory or industrial situation. 

Extraction isotherms of nitric, sulphuric, and hydrochloric acids in comparison with solvent extraction data (Figure 8.15) show that extraction capacity of TBP in TVEX resins. An increase of TBP capacity in TVEX-TBP is caused by the extractant state in the polymer matrix. The extraction capacity of mineral acids by TVEX-TBP decreases in the sequence HNO3 > H2SO4 > HCI (Figure 8.15a,b,c), and when compared with TBP solvent extraction performance, the capacity of the impregnated polymers exceeds 1.5 times the capacity of HNO3, 3.5 times that of HCI, and several times that of H2SO4. 

A considerable portion of the published data dealing with californium concerns the complexation and solvent extraction chemistry of Cf(iii). This is in part a consequence of the fact that a large amount of this information could be obtained using tracer quantities of the more abundant Cf isotope. In addition, there was an impetus to perform this type of study during the investigation/development of californium s separation chemistry. A compilation of stability constants for californium complexes and chelates is given in Table 11.9. 

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