The Chemistry of Uranium(VI) Orthophosphate Solutions Page: 3
The following text was automatically extracted from the image on this page using optical character recognition software:
were prepared froa reagent grade acids and their concen-
trations determined by titration against standardised sodiua
The nethod of continuous variations was applied to two
series of solutions. In one series, the acidity was adjusted
to approximately one solar with perchloric acid and the sun
of the analytical concentrations of uranlus(Vl) and phos-
phoric acid held at 0.137V. Twelve solutions were prepared
such that the uramlua(?l) concentration varied froa 16.7% to
100% of the sub of the uraniun(Vl) and phosphoric acid con-
In a second series of measurements, the acidity was
adjusted to approximately 0.1V with perchloric acid and the
sun of the uraniua(Vl) and phosphoric acid concentrations
was 0.014V. The ionic streugth of these solutions was held
approximately constant at 0.14V by the addition of C. P.
sodiua perchlorate. In these TJ. IV acid solutions, it was
necessary to reduce the uraniua( VT)-phosphoric acid concen-
tration level to 0.0141 in order to avoid the precipitation
of UO*HP04.4H20. As a result of this lover concentration,
it was found convenient to make optical density measurements
in the region of the ultraviolet (260-310 a/*)» where higher
aolar extinction coefficients are encountered, rather than
in the range 350-500 mp. used for the aore concentrated IV
RESULTS AND DISCUSSION
During the course of the continuous variation measure-
ments in one solar perchloric acid, coaplete spectral curves
were run on several of the solutions. These data are listed
in Table 1, and plotted in part in Figure 1. It Is evident
froa these curves that the addition of phosphoric acid
Increases the maxima of the uranlua(?I) absorption spectrua
and shifts thea to longer wavelengths.
The continuous rarlation results are plotted in
Figures 2 and 3 froa the data listed la Tables 2 and 3. In
the last column of these tables are Hated the calculated
values of the hydrogen ion concentration which would result
if no coaplexing occurred. These calculated final acidity
values are greater than one aolar because the D0t(ClO4)2
stock solution used in these measurements contained an
appreciable excess of free perchloric acid. The quantity
X which appears in the tables and figures is the ratio of
The total phosphate to the sun V of the total phosphate
and the total uranyl concentrat'fon in solution, t.e.,
Here’s what’s next.
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Baes, Charles F., Jr.; Schreyer, J. M. & Lesser, J. M. The Chemistry of Uranium(VI) Orthophosphate Solutions, report, June 22, 1953; [Oak Ridge, Tennessee]. (https://digital.library.unt.edu/ark:/67531/metadc172809/m1/6/: accessed May 20, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.