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Radiochemistry and Nuclear Chemistry
1
Selective Extraction of Americium Over Lanthanides
From Nitric Acid by DPTP
TANG Hong-bin，CHENG Qi-fu，YE Guo-an，YE Yu-xing，
JIANG De-xiang，ZHU Wen-bin，CHEN Hui
2,6-bis (5,6-di-n-propyl-1,2,4-triazin-3-yl)-pyridine (DPTP) was synthesized by using an improved
method. Considering the good solubility of DPTP and avoiding 3th-phase formation，30% octanoldodecane(ODOD) was selected as diluent. The distribution ratios of Am(Ⅲ) and Eu(Ⅲ) were studied as a
function of a number of parameters such as contact time，nitrate ion and the nitric acid concentrations in
aqueous phase，the concentration of DPTP in the organic phase. The results show that 5 min are enough to
reach the extraction equilibrium for Am(Ⅲ) and Eu(Ⅲ)，DM values increase obviously with increasing
aqueous nitric acid concentration，but the separation factor，SFAm/ Eu，are nearly constant in the range of
－
100-120 for this system. The distribution radios of La，Ce，Nd，Sm，Gd were measured to be 10 2 for
0.02 mol/L DPTP/ODOD.
Radiation stability of DPTP was studied，and the results show that DM was kept fixed when the
radiation dose is ≤103 Gy，and decreased obviously when the radiation dose is over 5104 Gy. The
americium can be re-extracted effectively from organic phase by 0.01 mol/L HNO3.
2 Study on Extraction Behavior of Am(Ⅲ) and Ln(Ⅲ) With iPr-BTP
CHENG Qi-fu，TANG Hong-bin，JIANG De-xiang，YE Guo-an，YE Yu-xing，ZHU Zhi-xuan
By using 30% n-octanol/n-dodecane as diluent ， the extraction behavior of Am(Ⅲ) and
lanthanides(Ⅲ) from nitric acid solution was studied with 2,6-bis-(5,6-di-i-propyl-1,2,4-triazin3-yl)-pyridine (iPr-BTP). The effect of some parameters，such as the concentration of nitric acid，the
concentration of iPr-BTP，diluent composition，ionic strength and the contact time on the distribution ratio
of Am(Ⅲ) and lanthanides(Ⅲ) is also investigated. The results show that the extraction equilibrium of Am
is reached within 5 min，however the kinetics of the extraction of Eu is slower，since equilibrium is only
reached after 15 min. When the concentration of HNO3 is in the range of 0.2-1.0 mol/L，the distribution of
Am(Ⅲ) and lanthanides(Ⅲ) is nearly constant. In addition，the composition of the extraction complexes
and the extraction reaction equation are examined，and it is found that the extraction reaction equation
may be expressed as follows：
M3+ +3NO3£- +3(iPr-BTP)O
M(NO3 )3  3(iPr-BTP)O
Finally，a conclusion is drawn that the capability of extracting Am by iPr-BTP is more than that of
extracting Eu，and the Am/Eu separation factor (SFAm/Eu) is 300 at 25 ℃，0.5 mol/L HNO3.
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
3
159
Study on Separation of Americium From Europium in Nitric Acid
by DPTP in Octanol-Dodecane
TANG Hong-bin，CHENG Qi-fu，YE Guo-an，YE Yu-xing，JIANG De-xiang，ZHANG Hu
According to our previous experiment results，0.02 mol/L DPTP/30% octanol-dodecane (ODOD)
was selected as the organic phase to separate americium from europium in 1.0 mol/L HNO3. After 4 stages
cross-flow extraction，the recovery of Am is 91.04%，only 2.93％ Eu follows with Am in the organic
solvent.
In order to increase the recovery of Am，a counter-current cascade (10 mL glass tube with plug)
extraction experiment was carried out with 0.04 mol/L DPTP/ODOD. In this experiments，the flow rate
ratio is as follow：X∶F∶ S=2.5∶ 4∶ 1，BF∶ BX =1∶ 1；the feed solution is Eu(Ⅲ)+1.0 mol/L HNO3，
scrubbing solution is 1.0 mol/L HNO3，stripping reagent is 0.01 mol/L HNO3. The results show that in the
extraction section the recovery of Am is 98.42％，only containing ＜0.9% Eu in the organic solvent，and
the stripping efficiency of Am and Eu is 99.9%，99%，respectively. The total separation factor is over 104.
4 Study on Reaction Kinetics of Nitrous Acid With Acetohydroxamic Acid
in HNO3 Medium
ZHENG Wei-fang，YAN Tai-hong，BIAN Xiao-yan
The kinetics of reaction of AHA with nitrous acid is studied in HNO3 medium. The reaction rate
equation was obtained as following：－ dc(HNO 2 )/dt=kc(HNO 2 )c 0 . 2 5 (AHA)c(HNO 3 ). In the case of
－
－
－
t=10 ℃，I=0.5 mol·kg 1，the reaction rate constant k is (0.481 4 ± 0.037 5) L1.25·mol 1.25·s 1. Reaction
－
rate constant k is increased a little with the increase of ion strength in the range of 0.5-3.0 mol·kg 1. The
effect of temperature on the reaction rate is also studied. The results show that with the increase of
temperature，the reaction rate increases quickly. The thermodynamic function of reaction under given
conditions was calculated，and ΔE is 46.92 kJ/mol. The mechanism of the reaction is discussed briefly.
5
Studies on Reaction Kinetics of Nitrous Acid With Acetohydroxamic Acid
in HClO4 Medium
YAN Tai-hong，ZHENG Wei-fang，BIAN Xiao-yan
The existence of HNO2 in the Pruex process will oxidate Pu(Ⅲ) to Pu(Ⅳ) quickly，so HNO2 must be
eliminated in the U/Pu cycle in order to stabilize Pu(Ⅲ). There are many papers report the reaction of
hydroxylamine, aldehyde, hydroxyurea and their derivatives. But the reaction of AHA with nitrous acid
has not been studied. So the kinetics of reaction of AHA with nitrous acid is studied in HClO4 medium.
The reaction rate equation is obtained as following：－dc(HNO2)/dt=kc(HNO2)c0.75(AHA) c0.5(HClO4). In
－
－
－
the case of t=5 ℃，I=0.5 mol·kg 1, the reaction rate constant k is (2.366 8 ± 0.214 7) L1.25·mol 1.25·s 1.
Reaction rate constant k is increased little with the increase of ion strength in the range of 0.5-2.0 mol·
－
kg 1. The effect of temperature on the reaction rate is also studied. The results show that with the increase
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Annual Report of China Institute of Atomic Energy 2005
of temperature，the reaction rate increases quickly. The thermodynamic function of reaction under given
conditions is calculated，and E is 99.02 kJ/mol. The mechanism of the reaction is discussed briefly.
6 Synthesis and Characterizations of Complexes of Rare Earth With Me-BTP
CHENG Qi-fu，TANG Hong-bin，YE Guo-an，YE Yu-xing
The salt RE(NO3)3·6H2O dissolved in ethanol is added to a CH3CN solution of ligand at room
temperature (the molar ratio of Me-BTP and RE(NO3)3·6H2O is 1∶ 1)，after being stirred at room
temperature for 6 h，and then mixture is standed overnight at 4 ℃. The precipitates produced in the
solution are separated by filtration，washed with CH3CN-ethanol (1∶ 1)，and dried. The yield of pure
product is 60%. Rear earth complexes with 2,6-bis-(5,6-di-methyl-1,2,4-triazin-3-yl)-pyridine (Me-BTP)
are prepared，and characterized by using elemental analysis，1H NMR，IR spectra and molar conductivity.
At 25 ℃，the molar conductivity of the complexes(1.0 mmol/L Nd(NO3)3 (Me-BTP)) is measured to
－
be 135 S·cm2·moL 1 (dissolved in DMSO). This fact shows the complexes are 1∶ 2 electrolyte. In
addition，Me-BTP is proved terdentate ligand，and three nitrogen atoms of the ligand are coordinated with
－
the metal ion by 1H NMR and IR spectra. The bands of 1 485 and 1 287 cm 1 in the complex are the two
split bands of the coordinated nitrate，which indicates that the nitrate is coordinated to the metal ion in a
－
bidentate fashion，and the bands at 1 384 cm 1 is assigned to the non-coordinated nitrate. These results are
accordant with the molar conductivity of the complex. Therefore，the compositions of rare earth
complexes may be confirmed to be [RE(NO3) (Me-BTP)] (NO3)2 (RE= La，Ce，Nd).
7
Measurement of Thermal Neutron Cross Section of 135Cs
WANG Xiu-feng，ZHANG Sheng-dong，QIAN Li-juan1，SUN Hong-qing，
GUO Jing-ru，CUI An-zhi，YANG Lei，DING You-qian
(1 College of Chemistry and Chemical Engineering，Lanzhou University，Lanzhou 730000，China)
The thermal neutron cross sections of the long-lived fission products are important for the study of
nuclei structure，partitioning-transmutation of radioactive waste，neutron activation analysis，and so on.
135Cs
emits pure β ray，and it has a half-life of 2.3×106 a and the high yield of 6.56% in 235U thermal
neutron induced fission. It is one of the most important nuclides for the disposal of high-level waste. Its
thermal neutron cross section has been measured for three times，but the two values of these results which
agreed well with each other were obtained by mess spectrometric method.
The thermal neutron cross section (σa) of 135Cs was measured by relative fission yield method in this
235U
target through measuring the radioactivity of
135Cs
atoms in the fission products by the fission
work. We obtained the fission number occurring in the
fission monitor
yields of
135Cs
137Cs，and
and
calculated the number of
137Cs. 197Au
and
55Mn
were selected to serve as neutron flux monitors when 135Cs was
activated. HPGe detector was used to measure the radioactivity of 136Cs for the activation of 135Cs.
In this work，235U targets were prepared and irradiated in heavy water research reactor(HWRR) of
CIAE. Each target contains about 100 g 235U solution. The solution was poured into a quartz tube with a
diameter about 4 mm，then dried under an infrared lamp. The tube was sealed and wrapped with an
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
161
aluminium foil，then housed in an aluminium can. The target was irradiated in HWRR for 7.2 d.
After cooling for seven months，the quartz target was dissolved and the cesium was separated. The
zirconium phosphate inorganic exchanger was used to separate carrier-free cesium from other fission
product nuclides. Because there is some undepleted U in the fission products，anion exchange resin
column must be used to decontaminate U. After fission product solution was passed through two times
zirconium phosphate column and two times anion exchange column，the chemical recovery of
137
Cs is
63%，the decontamination factor is 2.5×10 ，1.9×10 ，4.7×10 ，5.0×10 ，respectively Ce， Ce，
3
3
3
3
144
141
103
Ru，95Zr- 95Nb.
The target containing
137Cs
and
135Cs
was prepared，then the target and the neutron flux monitors
were housed in an aluminium can together for irradiation in HWRR of CIAE for 8 h. We measure the
radioactivity of
198Au
and
56Mn
at once after the irradiation，then calculate the neutron flux of the
activation. In the experiment，we found the measurement of 136Cs is interfered by 181Hf，185Hf and 24Na，
causing by the impurities of hafnium and sodium in the solution. After purifying it for the second time，the
interferents were removed.
The thermal neutron cross section of 135Cs is obtained by relative fission yield method in this work，
shown in Table 1. Comparing our value with the three reported values，the discrepancy is large. The
reason for this is checking and some detailed experiments will be performed.
Table 1
Thermal neutron cross section a of 135Cs
Author，time
Method
1028a/m2
Sugarman，1949
Radiochemical
14.5±4
Baerg et al.，1958
MS
8.7±0.5
Hatsukawa et al.，1998
MS
8.3±0.3
This work，2005
NAA-relative fission yield
2.55±0.10
8
Preparation of 242Cm
YANG Lei，ZHAO Ya-ping，JIN Xiao-jun1，ZHANG Sheng-dong，CUI An-zhi，GUO Jing-ru
(1 College of Chemistry and Chemical Engineering，Lanzhou University，Lanzhou 730000，China)
This work concerns in the preparation of carrier-free 242Cm (T1/2=162.8 d，α-decay). The 242Cm was

β
produced via reaction 241 Am(n, γ) 242 Am 
 242 Cm . The reaction cross section is 553×
T1/ 2 16 h
－28
10
m2，few reaction products are produced simultaneously. In order to prepare radiochemical pure
242Cm，the
anion ion exchange method in methanol-nitric acid system was adopted.
HZ210 anion resin with the size of 0.125-0.096 mm was selected and the exchange column’s
dimension is 1.7 mm×125 mm. Preliminary batch studies show that increasing concentrations of
CH3OH(75%，80%，90%) and HNO3(0.05，0.20，0.50，1.00，1.50 mol/L)，the distribution coefficient
of 241Am on HZ201 resin is increased. At the same time，the content of CH3OH in CH3OH-HNO3 system
had much less influence on distribution of
241Am
while acidity is raised. Therefore，the separation
conditions were established as follows：90%CH3OH-1.5 mol/L HNO3 as washing solution，90%
CH3OH-0.05 mol/L HNO3 as eluate，and flow rate of 0.043 mL/min. The eluant was monitored using a
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Annual Report of China Institute of Atomic Energy 2005
NaI(Tl) γ-spectrometer，a α-spectrometer and a HPGe γ-spectrometer. Finally，the results of separation are
as follows：total recovery of
242
Cm is more than 90% and decontamination factor of
241
Am is over 103
while a fit fraction is choosed by elution curve .
The 241Am target containing 27.6 μg 241Am was irradiated in the reactor with an average neutron flux
－2
density of about 2×1013 cm
－1
·s
for 8 d. After cooling half month，the irradiated target was dissolved in
1 mol/L HNO3 solution and converted to 0.5 mL 90%CH3OH-1 mol/L HNO3 solution. Using the above
procedure，the total activity of
some products such as
9
140
242Cm
140
is 3.96 MBq and the
95
95
103
241Am
La， Ba， Nb， Zr， Ru and
activity is 0.045% and γ-activity from
152
Eu is about 0.003%.
Study on Preparation Radiochemical of Pure 91Sr
YANG Zhi-hong，DING You-qian，ZHANG Sheng-dong，Cui An-zhi
For measuring the decay data of 91Sr，it is necessary that the radiochemical pure 91Sr is firstly
prepared. Based on the analysis of the correlative decay chains shows in Fig.1，twice delay separation
method[1] is adopted to prepare radiochemical pure 91Sr. In this method 235U target is irradiated for short
time，and delayed for about 1 min to allow 92Rb and 93Rb completely decay to 92Sr and 93Sr，then Rb is
quickly separated；Delaying for about 10 min to allow the 91Rb decaies to 91Sr，and then 91Sr is separated
and purified from other impurities.
Fig.1
Correlative decay chains
An 18-crown-6(DCHC) exists obvious aperture-diameter effect on Sr，and can efficiently extract Sr[2].
The crown ether was synthesized an extraction chromatographic resin (Sr·spec EIChrom Industries，Inc.)
that can rapidly separate Sr from a number of other elements at 3 mol/L HNO3 medium，while Ba is more
strongly retained than most other interfering species. Ba can be removed by washing with a sufficient
volume of nitric acid (30 free column volumes)，and Sr can easily be elutriated by H2O or 0.05 mol/L
HNO3.
Based on the Sr·spec resin，we prepared a similar material. The 18-crown-6 was loaded on Kel-F and
Amberlite XAD-7 inert supports，respectively，and the sorption and elution experiments were performed
using the
85Sr
tracer. The results indicate that above two chromatographic materials can be used to
separate Sr. A procedure of using two crown ether extraction chromatographic columns was designed，and
the first column was used to abstract Rb，the second column to purify Sr. A rapid automatic separation
device of 91Sr was made. Using this device，the separation procedure of 91Sr was validated by the mixed
fission products. The first separation of Rb/Sr is performed within 50 s，and whole procedure separation
time is 200 s. The chemical recovery of Sr is (93±5)%，and the decontamination factors of radionuclides
are higher than 103.
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
163
References：
[1]
DING Youqian，CUI Anzhi，YANG Zhihong，et al. Separation of 142La from fission products by HDEHP[J]. J Nucl
Radiochem，2003，25(4)：219-222.
[2]
HORWITZ E P，CHIARIZIA R，DIETZ M L. A novel strontium-selective extraction chromatographic resin[J]. Sol
Extr Ion Exch，1992，10(2)：313-336.
10
Separation of Trace 173,174Lu From Gramme Yb
DING You-qian，MAO Guoshu，YANG Zhi-hong，CUI An-zhi，
ZHAO Ya-ping，SONG Zhi-jun，SHI Keliang
173,174Lu
are produced by Yb(p, n) and (p, 2n) reactions on tandem accelerator. In order to measure
decay data of 173,174Lu，the separation of trace 173,174Lu from gramme Yb is necessary. Simultaneously Yb
amount must be less than 50 μg in the sample for measuring 173,174Lu with mass spectrography.
This work concerns in the separation of trace 173,174Lu from gramme Yb，and some conditions were
studied with a cation exchange column and α-HIBA (α-hydroxyisobutyric acid) as eluent. The influences
of column temperature and Yb loading amount were studied by two exchange columns with 4 mm×
500 mm and 20 mm×500 mm, respectively. The results show that the separation efficiency increases
with increasing temperature and decreases，especially at 40 ℃，with increasing Yb loading amount. At
80 ℃，if the load of small column is over 60 mg and big column is over 200 mg，the precipitation will
occur in the exchange column. Based on above experimental results，20 mm×500 mm cation exchange
column at the temperature of 55 ℃ were selected.
After cation exchange separation，the Yb amount in the separated sample is much greater than
50 g，and the α-HIBA solution must be eliminated for measuring 173,174Lu with the mass spectrography.
So，the following purification based on the hydroxide precipitation and extraction chromatography
processes is necessary. The hydroxide precipitation method is more effective and convenient for the
isolation of α-HIBA in the sample with much Yb amount，and the ion extraction chromatography method
is suitable for the sample with less Yb amount.
The typical separation process is as follows：
1) The irradiated sample about 600 mg is dissolved in 5 mL concentrated HCl solution；
2) The solution is evaporated to dry and dissolved in 2 mL 0.01 mol/L HNO3 solution；
3) The dissolved solution is adsorbed in 20 mm×500 mm cation exchange column，and then is
elutriated with 0.07 mol/L α-HIBA with pH=6.13 at flow rate of 5 mL/min and temperature of 55 ℃；
4) Collecting the eluate 10 mL in a centrifuge tube，and the amount of
173,174Lu
NaI(Tl) γ-spectrometer，Yb is measured by spectrophotometer，the recovery ratio of
are measured by
173,174Lu
is over 99%
and the Yb amount is 108 mg in all collected fractions；
5) The collected eluate is adjusted with saturated NaOH solution to pH=13-14，and the Lu(OH)3 and
Yb(OH)3 are precipitated quantitatively，the precipitants are filtrated and dissolved in 6 mol/L HNO3
solution，then 2) and 3) steps are repeated，73,174Lu about 98% and Yb <40 g are obtained in the 6 mol/L
HNO3 solution；
6) The HNO3 solution is adjusted to be pH=1.0-1.5 with concentrated HCl，and is absorbed in the
chromatographic column，then is desorbed with 40 mL 9 mol/L HCl solution at flow rate of 1.5 mL/min
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Annual Report of China Institute of Atomic Energy 2005
and room temperature；
7) The solution obtained from 6) is evaporated to dry and solubilized in 3 mL 0.5 mol/L HNO3
solution，the solution can directly be used for measuring
173,174Lu
and Yb with HPGe detector and mass
spectrometer，respectively.
11
Separation of Carrier-Free 107Pd From High-Level Liquid Waste
LIANG Xiao-hu，ZHANG Sheng-dong，GUO Jing-ru，MAO Guo-shu，SUN Hong-qing
is a long-lived fission product with a half-life of 6.5×106 a. Nuclear data measurements of 107Pd
are very important to both the basic research and the disposal of the high-level wastes. In this work we
developed a new separation method to separate carrier-free 107Pd with high radiochemical purity from the
high-level liquid waste.
The separation methods of Pd from high-level liquid waste(HLLW) include precipitation，liquid
extraction and ion-exchange. Based on the high selectivity of the complex of Pd2+ and dimethylglyoxime
(DMG)，we developed the chromatography.
The chromatogram column with 5 mm diameter is filled with 0.15 g AmberliterXAD-7 resin loaded
1 mg DMG. The 1 mL 1 mol/L HNO3 solution containing HLLW is fed to the resin column，the palladium
is adsorbed on the resin due to format DMG-Pd complex. Then the column is eluted with 10 mL 1 mol/L
HNO3 to remove impurities，Finally，5 mL methanol was added to desorb palladium from the column. All
of the elution operations are controlled at a flow rate of 0.1-0.15 mL/min.
Using 109Pd as a tracer the palladium recovery of this process was determined to be 75%-95% and
the decontamination factors(DF) of some nuclides are given in Table 1.
107Pd
Table 1
Decontamination factors of the main nuclides
Nuclide
DF
Nuclide
DF
90Sr
3.5×106
95Zr
2.6×104
103Ru
1.2×103
144Ce
>1.4×104
95Nb
1.8×104
75Se
8.2×103
123Sn
1.3×103
137Cs
1.8×105
99Tc
8×102
237Np
5×102
233U
8.1×103
111Ag
23.5
125Sb
6.3×103
12
Sorption Behavior of Hafnium on Ion Exchangers
YANG Lei，MAO Guo-shu，ZHANG Sheng-dong，GUO Jing-ru
In this work，we have studied the sorption behavior of hafnium on anion and cation resins.
The type of anion resin is 201×7 (74-100 μm) and cation resin type is 2×8 (50-120 μm). The volume
of exchange column (Vc) is 0.8 mL (3 mm×12.2 cm). The eluents are 0.5 mol/L HCl-0.001 mol/L HF，
0.05 mol/L HCl-0.001 mol/L HF，respectively. The flow rate is 0.25 mL/min and 0.07 mL/min，
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
165
respectively in anion and cation exchange columns. Counts of γ-rays were measured with NaI(Tl) and
HPGe. The trace of hafnium is 175Hf (T1/2=70 d)，which was produced by irradiating HfO2 in miniature
neutron source reactor (MNSR) at China Institute of Atomic Energy.
The experimental steps are as follows：
1) Adding some 175Hf tracer solution on the top of exchange column；
2) Eluting by 0.05 mol/L HCl-0.001 mol/L HF or 0.5 mol/L HCl-0.001 mol/L HF mixed solution；
3) Receiving the eluent every 0.2 mL in γ counting tube.
First，we use 0.5 mol/L HCl-0.001 mol/L HF mixed solution as the eluent to study the sorption
behavior of hafnium on cation and anion resins. The elution curve is given in Fig.1.
Fig.1
Elution curve of hafnium
◇—Anion resin exchanger；△—Cation resin exchanger
From Fig.1 it is seen that the sorption of hafnium is very weak on the anion exchanger. While the
sorption of hafnium on the cation exchanger is to some extent，so hafnium is eluted out from the 10 Vc and
finished till the 17 Vc. Therefore，it is confident that hafnium should be some kind of cation form，like
－
HfF62 .
Then the 0.05 mol/L HCl-0.001 mol/L HF was used as elution. In the case of 0.05 mol/L HCl0.001 mol/L HF medium the sorption behavior of hafnium is opposite to that in 0.5mol/L HCl-0.001
mol/L HF medium. For cation exchanger，hafnium is eluted out with 1.5Vc，and strongly sorbed for anion
－
exchanger. The fact indicates that the existence form of hafnium is anion，probably HfF62 .
13 Sorption Behaviour of W on Ion Exchangers
MAO Guo-shu，YANG Lei，ZHANG Sheng-dong
The half-life of 182Hf is long (T1/2=9×106 a) and the content of 182Hf is very low，accelerator mass
spectrometry(AMS) must be used to detect it. However，the stable isobar 182W is a main interference for
the AMS measurement of 182Hf. Therefore，the research on the behaviour of W is interesting in the process
of separating Hf.
The ion exchangers method was adopted to separate Hf，and the sorption behaviour of W on cation
and anion exchangers at HCl/HF mixed medium. In our experiment，187W(T1/2=23.9 h，from 186W(n,
γ)187W reaction) was used as a tracer of W.
The HZ 201 anion exchanger resin (74-100 μm) and 2×8 cation exchanger resin (50-120 μm) is filled
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Annual Report of China Institute of Atomic Energy 2005
to the columns(3 mm×12.2 cm) with the volume of column(Vc) of 0.8 mL，respectively. The elution was
operated at flow rates of 0.25 mL/min (anion column) and 0.07 mL/min (cation column). Count of γ-rays
from 187W was measured with NaI(Tl) and HPGe γ-spectrometers.
0.05 mol/L HCl-0.001 mol/L HF solutions used as eluent，the sorption behaviour of stable W with
various quantities on cation and anion exchangers was studied.
Results show that for 0.05 mol/L HCl-0.001 mol/L HF mixed medium W (mW<4.2 g) is adsorbed
strongly on anion exchanger，it passes beyond the cation exchanger with a recovery of 98% within 2Vc. It
proves W is anion ion in 0.05 mol/L HCl-0.001 mol/L HF mixed medium.
Using 0.5 mol/L HCl-0.001 mol/L HF solutions as the eluent，the sorption behaviour of W with
various quantities on cation and anion exchangers is also studied. The result is shown in Fig. 1.
Fig.1
Elution curve of W on anion exchanger(a) and cation exchanger(b)
in the case of 0.5 mol/L HCl-0.001 mol/L HF mixed medium
From the elution curves it is seen that W passes beyond the anion and cation exchangers at 0.5 mol/L
HCl-0.001 mol/L HF mixed medium. But the elution curves of W on anion and cation exchangers
represent a little different. 98% of W is eluted within 4Vc on cation exchanger，however，98% of W is
eluted within 10Vc on anion exchanger.
14
Development of Target (Source) Preparation Technique
With Pulse Electroplating
YANG Chun-li，SU Shu-xin，ZHANG Sheng-dong
Electroplating，also called as electrodeposition，is the most widely used method in the preparation of
sources and targets of actinides. This method has many advantages，such as high deposition yields，simple
devices，easily operation and can obtain homogeneous and adherent deposition on the film.
The common electrodeposition method is applied with direct current power supply. The source
prepared with this method has high interstress，limited thickness and easily cracks. In recent years，a kind
of new technique for source preparation was developed. This new technique adopts pulse power supply
which can not only improve current efficiency but also the density，purity and homogeneity of the source.
This new method can be used to prepare thicker source and target with the thickness above 150 mg/cm2. It
breaks through the restriction of direct current electroplating method and proves to be a very promising
technique for source and target preparation.
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
167
On the basic of feasibility verifying of pulse electroplating in 2005，various parameters of pulse
electroplating for U in DMF were investigated，including current density，deposition time，concentration
of the electroplating solution and so on. The optimum condition of pulse electroplating is preliminarily
determined as follows：anode，Pt spiral wire with 1 mm；cathode，stainless steel piece with 30 mm；
current density，1-5 mA/cm2；solution volume，10 mL DMF；deposition time，30 min；U concentration
of electroplating solution，0.2-5 g/L.
Under this condition，an adherent and homogeneous uranium source was prepared. The surface
density prepared U source reaches above 3 mg/cm2，which far exceeds the density of that prepared by the
direct current electroplating. In addition，the layer is more adherent.
At the same time，two characterizations for the uranium sources are made，including homogeneity
and the morphological structure measurement. In order to measure the homogeneity，α counting and
thickness measurements instrument were used. The results of measurement show that U is not uniformly
distributed on the substrate and the deposition on the center of the layer is more uniform and thicker than
that on the edge. The thickness is in the range of 1.3 μm and 7.4 μm. The observation for the
morphological structure shows that there are many cracks on the layer. Some of the cracks plunge into the
substrate，which demonstrates that the deposition is difficult to peel and is highly adherent.
15 Study and Installation of Graphite Crystal Pre-diffraction Energy Dispersion
X-ray Fluorometry and Application in Anglicizing HLLW Sample
WU Ji-zong，ZHENG Wei-ming，JIN Li-yun，HUANG Qing-liang，
SONG You，LIU Gui-jiao，ZHANG Li-hua，FAN De-jun
A graphite crystal pre-diffraction-EDXRF analysis system is designed and constructed with an
appropriative low-power Ag target X-ray tube as exciting source. The minimum detection limit of this
analysis system is 0.26 μg/mL for uranium. A series of actinide and fission products in energy range of
13-20 keV can be determined simultaneously. Ag target scattered X-ray as internal standard methods were
developed. The methods can effectively correct the variations of voltage-current and matrix absorption
effects. The actinide and fission products can be determined nondestructively and directly. The precision
of method(RSD) is 2%-11%. The traditional cell of Mylar film window are substituted by a kind of
commercial cell to ensure safe operation of 1AW sample. The contents of U and Zr in HLLW was
determined by this analysis system，the result is consistent with the result determined by photo-spectrometry after separation. U, Np, Mo, Zr, Ru, Tc in 1AW sample from nuclear fuel reprocessing frame
experiments is analyzed rapidly. It’s an ideal control analysis method for 1AW sample.
16
Separation and Determination of Pu and Np in Existence
of Large Quantityof Uranium:
Establishment and Application
of Argon Pressurized Anion-Exchange Evacuated Column System
LIU Quan-wei，XIAO Guo-ping，WU Ji-zong，YANG Da-ting，ZHANG Yong-zhen
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Annual Report of China Institute of Atomic Energy 2005
Np and Pu in the uranium product must strictly be controlled in spent fuel reprocessing process.
Determination of Np，Pu in uranium product needs accuracy，stability and efficiency for uranium product
quality control. Direct measurement of them is not applicable because both the U/Pu and U/Np ratios are
extraordinary large. So，the development of the high efficiency separation procedure for measurement of
Np and Pu in the uranium product is important for the quality control in spent fuel reprocessing process.
In this study，argon pressurized anion-exchange evacuated column system was established for
effective separation of Pu and Np from the simulated uranium product specimen at one time. After
separation, Np and Pu were measured with large area grid ionization chamber-alpha spectrometry. The
result shows argon pressurized anion-exchange evacuated column system effectively improves the
decontamination factor of uranium and accelerates the separation process. Consequently，the determination of Np, Pu in uranium product meets the requirement of uranium product quality control. the
separation coefficients of Pu and Np are greater than 105，and the recovery is 78% and 87%，respectively
for Np and Pu.
17 Accurate Measurement of Isotope Ratio of Trace Plutonium in Uranium Matrix
by Multi-collector Inductively Coupled Plasma Mass Spectrometry
LI Li-li，LI Jin-ying，ZHAO Yong-gang，ZHANG Ji-long，WANG Tong-xing
An efficient separation procedure for trace plutonium from uranium matrix by TBP and aliphatic
quaternary amine chromatographic extraction was developed. Various factors in the chromatographic
extraction separation process were optimized experimentally. The decontamination factors of the
separation procedure attain to 107 for uranium and the recovery of plutonium is more than 98% when the
－
content of uranium is 0.1 g and that of plutonium is 610 9 g. The separation procedure is considered to
be suitable totally for the request of the accurate measurement of the isotope ratio of trace plutonium with
uranium matrix by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). A series
of experiments which optimize the factors affecting the isotope ratio of trace plutonium have been
performed in MC-ICP-MS with plutonium reference material，and an operating prescript has been
formalized. By applying the process of extraction chromatography and the MC-ICP-MS，the isotope ratios
of trace plutonium in reprocessed uranium samples were measured accurately.
18 Study on Rapid Determination of Uranium in Uranium Line of Purex Process
WU Ji-zong，ZHANG Li-hua，QIAN Hong-Juan，LIU Huan-liang
A new masking and buffer system (Zn-EDTA-EDTA) is proposed by studying the rules of EDTA
reaction with the analyte (UO22+) and interferents (Fe3+，Zr4+，Cr3+). A system composing of Zn-EDTA and
EDTA can be used as masking agent instead of DCTA which is prone-precipitation. And the system also
can be used as buffer agent instead of chloroacetic acid and its salt which will erode the stainless steel
FUNDAMENTAL AND APPLIED FUNDAMENTAL RESEARCH·Radiochemistry and Nuclear Chemistry
169
facilities such as the waste liquid tube.
A fast analytical procedure for determination of the uranium concentration in the uranium line of
Purex process is established. Conformity to Beer’s law was obtained within the scope of 0.04-1.5 g/L. For
determination of uranium，the precision is better than 0.54%．The procedure can be performed with two
steps. The acidity of sample in the range of 0.1-2 mol/L have no obvious deference in the analysis results.
The procedure is very useful for process control and can be automated easily.
19
Determination of U and Zr in Special Organic Radioactive Sample
by Graphite Crystal Pre-diffraction-EDXRF Analysis
ZHENG Wei-ming，SONG You，LIU Gui-jiao
A method is proposed for the graphite crystal pre-diffraction EDXRF analysis of U and Zr
concentration in jelly organic waste after decades deposition from spent fuel reprocessing plant. After
pre-processing，the jelly is divided into two parts，aqueous phase and organic phase. The concentration of
Zr in some aqueous phase samples is so high that the influence of Zr to U can’t be eliminated by Ag
scattering inner standard method，so two steps are adopted to detect the aqueous phase samples. Firstly，
the concentration of Zr is obtained by calibration curve of Zr，then，Zr with known amount is added into
the standard series of U，and the concentration of Zr must be equal to the determied value，so the influence
of Zr to U is eliminated by matrix-matching. Finally，the concentration of U is obtained by measuring the
sample and the standard series of U. It’s necessary to prepare the standard of Zr in organic phase because
no commercial referrence material can be obtained. ZrO(NO3)2·2H2O powder is dissolved in 7 mol/L
HNO3 and deposited a day，the solution is filtrated and the concentration of Zr in the filtrate is detected by
titrating using EDTA. The Zr in the aqueous phase is extracted by TBP-OK(30%)，then the concentration
of Zr in aqueous phase is determined in the same way above. The concentration of Zr in organic phase can
be obtained from the concentration difference of Zr in the aqueous phase pre-and-after extraction.
20
Determination of Lithium in Organic Phase by Spectrophotometry
ZHANG Li-hua，LIU Huan-liang，ZHANG Yong-zhen
In the study of extracting lithium with crown ether，it is necessary to determine the concentration of
the lithium in organic phase. Based on the fact that the organic phase containing lithium is easily resolved
in the measuring medium，a simple and exact method for determination of trace lithium in organic phase
is developed．
Experimentally，the best measuring condition for determination of the lithium in organic phase is
obtained as follows：0.2% thoron is used as developer，20% potassium hydroxide is used to adjust
alkalescence of the solution in the method，lithium-thoron complex is developed in acetone-water
medium，485 nm is the measuring wavelength.
A procedure for determination of trace lithium in organic phase is established，and the interference of
－
Ca，Mg，Zr，Fe，Na，SCN ，NH4+ and crown ether to determination of the lithium concentration in organic
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Annual Report of China Institute of Atomic Energy 2005
phase is examined. The conformity to Beer’s law is obtained within the scope of 0.1-5 g of lithium per
10 mL. The precision of measurement is 4.0%，and the recover of lithium is 97%-107%.