ANALYTICAL CHEMISTRY
612
present in the original solution. The effiuents coiitaining dichromic acid were titrated to the second end point n-hich corresponded to the chromate rather than the dichromate ion. At the above flow rate through the column the resin capacity a-as about 3 to 4 meq. per cubic centimeter of wet resin. .I wmple could be analyzed in approximately 20 minutes including titration time. The resin was regenerated easily by washing with 3M sulfuric acid followed by distilled water. Using the procedure described, nine samples were an:dyzeti for sulfate. The mole equivalent ratio of sulfate to uranium was varied from 0.75 to 1.12. Additional analyses were made in the same manner a t approximately 0.83, 1.0, and 1.25 equivalents of anion per equivalent of uranium; the anion was, in succession, nitrate, chloride, perchlorate, and dichromate. The expeeriment:iI data are given in Table I. DISCUSSION
T h e nver:tye dcviution of tlic icsultq from the actual amount
of anion present was about =tO.l5%. Investigations by other groups at this laboratory (1, 3 ) have indirated equal success with uranyl fluoride solutions. The bulk of this investigation was carried out with the above mentioned resin; however, later work has shown that elution times can be shortened by using a snialler mesh resin. LITERLTURE CITE11
(1) 1I;dgci.ton J. H.. et a [ . , .Inalytical (’hemistry Division, Ridge Xational Laboratory, Oak Ridge, Te:in., private munication, 1952. ( 2 ) Samuelson, O., “Ion Exchangers in .In:tlytical C h e m i s t q , ” York, John TViley 8: Sons, 1953. (3) Stephens. I,. d.,et al., .Ina!ytical Chemistry Division, Plant, Oak Ridge, Tenn., g r i r a t e communication, 1952.
Oak comSen-
T-12
RECEIVED f o r review lfarcli 2 6 . 1953. Accepted riugust 20. 19.53.
Preparation and Properties of 4,7-Dimethylindan JACOB ENTEL Coal Research Laboratory, Carnegie Institute of Technology, Pittsburgh,
infrared and ultraviolet spectra and other physical proper1 ties of synthetic 4,i-dimcthylindan are reported, and are a useful supplement to the table of properties which have been
I
THE
I
Pa. I
I
I
I
5 2 q -.
I
-
givcn for 10 previously described methylated indans ( 1 ) . No further work is contemplated on this series of compounds. 20
EXPERIJIEYTLL
--
.-
-
w
Three hundred sixty grams of 4,7-dimethyl-l-indanone, prepared as described by Hart and Tebbe (a), was reduced as described by Plattner and WVSP(3). The resulting product was carefully fractionated in a column of 20 theoretical plates to yield 273 grams or 62% of theory of 1,i-tliniethylinclaii.
” 0
I 1.5
-
j ~~
-~~
Physical Properties of 4,i’-Dimethyliiidan
B.P., C. 2 2 7 . 6 at 745.5 mni.
71’D”
1.5321
da”
0.9478
Specific Refraction 0.3273
Molar
-
ACKNOWLEDGMEST
!+ ,t
10220
260
300
Refraction Olisd. Calcd.
47.80
w i t h t (3). ported h o s e The p r e vinfrared i o u s l y and reultraviolet spectra of 4;T-dimethylindan are shown in Figures 1 and 2. The methods for the determination of these properties have been described ( I ) .
-
4,7- OIMETHYLINDAN
Table I .
~ o n i l ~ u i i dIvhich , are sliown in Table I, are in agreement
47.20
The “heart cut” of this fractionation was used for measurcments of physical properties. The physical properties of this
Figure 1. Infrared Spectrum of 4,?-Uimethylindan
The assistance of Joseph B. Sinisic and Daniel T. Muth is gratefully acknowledged.