) 67Ga
331.1
1418.2
65Zn
1.3
5.6
As shown in Table. 3, distribution coefficients un-
3.2.2. Relation between extraction time and ex-
der the kinetic condition were 5% (for Ga) and 9% (for
change ratio ( F) on the column
Zn) higher than ones under the static condition. Equilib-
Variation of exchange ratio of 67Ga (non-radioactive
rium coefficient of Ga was 253.3 times higher than one
Ga concentration; 450μg·mL-1) by time on extractant
of Zn. It showed that extraction rate of Ga was faster resin column was shown as Fig. 1.
than Zn, respectably.
% , 1,2
o
ati
1
reg 0,8
anh 0,6
c
277K
x e 0,4
289K
Ga
308K
0,2
0
0
5
10
15
20
25
extraction time,min
Figure 1. variation of extractability of Ga by time on extractant resin column
As shown in Fig.1, on extractant resin column ex-
67Ga extraction velocity constants and film distribu-
traction equilibrium time of 67Ga was 11min at 308K,
tion coefficient on the column by temperature were
18min at 291K and 24min at 277K.
shown in Table.4.
3.2.3. Kinetics of 67Ga extraction on the column
Table 4.
67Ga extraction rate constants and film distribution coefficient on the column by temperature Temperature (K)
277
289
308
Rate constant ( β)
0.107
0.074
0.218
film distribution coefficient ( Df)
8.0×10-6
5.8×10-5
1.12×10-5
48
Журнал «Интернаука»
№ 16 (145), часть 3, 2020 г.
By experimental results, it was found that during
and Bt was determined while 67Ga was extracted on early period of column process, film diffusion was rate-extraction chromatograph column. Relation between t determining step and after that, gel diffusion was rate-and Bt at 289K was shown in Fig.2.
determining step. So relation between extraction time
3,5
3
Bt
2,5
2
1,5
1
0,5
0
0
5
10
15
20
t, min
Figure 2. Relation between t and Bt (289K) for Ga extraction on the column
By t-Bt relation at 289K, extraction reaction rate static condition and column equilibrium constant of Ga
constant was 0.23cm-1. So on extractant polymer resin was 254.7times higher than Zn. While 67Ga extracted to
column, extraction process of 67Ga was assumed to be extractant resin was back extracted with 0.05mol·L-1
simultaneous process of film diffusion and gel diffusion.
HCl solution, back-extractability under the static condi-
Activation energy of extraction reaction on the column tion was only 15~20%, but was 94% under the dynamic
determined from relation between lnβ and 1/T was condition and it was found that dynamic condition had E*=14.92kJ·mol-1.