The work is devoted to technology electrochemical obtain powder of zirconium ion fluoride melts (set-ting parameters of the electrolysis method of washing powder Zr impurities from salt mixture components) on different substrates. Phase and element composition and cell size distribution of powdered zirconium was investigated.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3551

Protsenko, Z.М.

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PROCEEDINGS OF THE INTERNATIONAL CONFERENCE  NANOMATERIALS: APPLICATIONS AND PROPERTIES Vol. 2 No 4, 04NEA11(3pp) (2013)   2304-1862/2013/2(4) 04NEA11(3) 04NEA11-1  2013 Sumy State University Technology Features an Electrochemical Obtain Powdered Zirconium  Z.М. Protsenko*  Sumy State Pedagogical University, 87, Romenska Str., 40001 Sumy, Ukraine,    (Received 16 June 2013; published online 03 September 2013)  The work is devoted to technology electrochemical obtain powder of zirconium ion fluoride melts (set-ting parameters of the electrolysis method of washing powder Zr impurities from salt mixture components) on different substrates. Phase and element composition and cell size distribution of powdered zirconium was investigated.  Keywords: Powdered Zirconium, Electrolysis, Phase and Elemental Composition.    PACS numbers: 81.15.-z, 81.40.Cd PACS number(s): 00.00.Хх, 00.00.Хх                                                             * zoya.protsenko@i.ua  1. INTRODUCTION  Now there are several methods for preparing zirco-nium in powder, and massive state. Zirconium is widely used in nuclear energy, space technology, electronics, chemical industry and other branches of engineering. Ability to use zirconium in many cases depends on its purity. For nuclear power to create structural reactor blocks them (shells of fuel elements fuel, ducted pipes) are requirements for purity zirconium a relatively oxy-gen, nitrogen, carbon (less than 0.05, 0.006, 0.005 at.%, respectively). For example, in works [1, 2] paid atten-tion to obtaining high-purity and nuclear-purity zirco-nium. To obtain high-purity metals, including zirconi-um, the authors of work [1] proposed the application at various stages of refining of complex chemical or physi-cal and chemical methods. To obtain nuclear-pure zir-conium and alloys based on zirconium with magnesium thermal or iodide zirconium devoted to the work [2]. For the reprocessing of spent nuclear fuel, promis-ing electrochemical method for electron electroreduc-tion Zr fluoride of salt melts. Although the problem electroreduction of Zr salt melts considerable attention in the work of domestic and foreign authors [2-6], there are still many unexplored and clarified points, so the subject study on the electroreduction of fluoride Zr al-loys is important. The aim of this study was to establish the optimal process parameters of electrolysis, obtaining powdered Zr, washing it from impurities and establishment of phase and elemental composition and granule size dis-tribution of powder product.  2. EXPERIMENTAL МЕTHODIC  For the electrolysis was elected two eutectic mix-tures  based  on  NaF-ZrF4:  NaF  (50,5 ml.%) - ZrF4 (49,5 mol.%), 500 оC and  NaF (59,5 ml.%)-ZrF4 (40.5 ml.%), 512 оC. Anode served graphite was used as the cathode plate of copper, brass, bronze, zirconium, stain-less steel. Electrolysis was carried out for 2-4 hours in the galvanic static mode under argon. Temperature was asked within 570-770 оC, cathode current density of 0.2 - 0.5 A/cm2. Purified from salt impurities by de-cantation in hot water, acidified hydrochloric acid pow-der residue analyzed by X-ray diffraction (DRON dif-fractometer - 4.0 in К  radiation Cu) and  mass  spec-trometry (mass spectrometer MS-7201) analysis. The elemental and granule composition of the product was determined by scanning microscope REMMA-102-02.  3. EXPERIMENTAL RESULTS  Selection to melt electrolysis caused by both physi-cal and chemical properties of the salt mixture (rela-tively high melting point, no volatility, resistance to heat, the solubility of zirconia in it), and associated with the possible use of these systems in nuclear pow-er. The experiment was conducted in order to choose the material electrode - cathode, not corroded in the studied salt mixture is not formed from zirconium dep-osition temperature of its chemical compounds. The important point was to establish the parameters of the process of electrolysis to produce dense precipitate of zirconium powder with minimal salt impurities mini-mum loss (dissipation) powder in the melt and subse-quent easy removal of it from the substrate.  Dependence of mass increase cathode (for different materials) of the current density with a parabolic form, indicating the diffusion control process electroreduction zirconium.  When choosing the optimum current density and the cathode material into account primarily mass of sediment (at the same time and temperature electroly-sis), the content in the sediment of salt impurities, the density of sediment and the ease of its removal from the substrate. Note that in all cases the deposit on the substrate was in the form growths dendrites that are removed mechanically. As follows from the experi-mental data, the best results are obtained when using as substrate zirconium (the largest daily gain, the smallest impurities including salt), but it was great complications in the removal of sediment from the sub-strate, so we can recommend to use as a cathode sub-strates, brass, or copper. In addition, based on experi-mental data and Faraday's law was calculated output current for powdered zirconium, this value is 86%  Z.M. PROTSENKO PROC. NAP2, 04NEA11 (2013)   04NEA11-2 (cathode-zirconium), 80% (brass), 74% (steel). Reduced value of the output current can be ex-plained by the partial loss of zirconium in the melt and in washing. Obtained and purified from salt impurities zirconia powder was analyzed by X-ray diffraction analysis to determine the phase composition of the product. For example, Figure 1 shows a fragment of the X-ray pat-tern obtained on the substrate of zirconium.  0204060801001200 20 40 60 80 100  2θ, degree  Fig. 1 – X-ray pattern for powder product of electrolysis ob-tain on zirconium substrate  After decoding of radiographs, found that all the lines correspond to the same phase - the phase of zirco-nium impurity phases were found, although the X-ray analysis reveals no trace. Similar results we obtained in the case of a substrate with brass. In Table 1 for ex-ample the results of XRD analysis, the resulting pow-der lined with brass. Found that all the lines corre-spond to the phase of zirconia, but recorded each radio-graph as several lines (on the background), which can be attributed to the phase of ZrO2, ie powder contained not a large percentage of impurity phase (less than 1%).  Таble 1 – X-ray analysis of the electrolysis products (pow-dered zirconium) on brass substrate  № Experimental data Таble data for Zr 2θ, degree d, Å I, % d, Å I, % 1 31,85 2,8096 54 2,780 33 2 34,45 2,6033 51 2,573 32 3 36,35 2,4714 100 2,459 100 5 47,65 1,9084 47 1,894 17 6 56,70 1,6234 50 1,616 17 7 62,95 1,4764 46 1,463 18 8 68,05 1,3777 45 1,368 18 9 69,20 1,3576 41 1,350 12  Elemental and granular size distribution of powder precipitate Zr was determined by X-ray microanalysis (PMA) and electron microscopy. Microstructure on Fig. 2a clearly shows that dust does not have a clear crys-talline structure, their size is (2 - 20) microns. On Fig. 2b presents EDAX spectrum of powder products of elec-trolysis, shot wave dispersion spectrometer. In the in-set is represented the elemental composition (wt.%) zirconium powder precipitate corresponding Zr and doped elements K, Cl (artificially brought about during washing) and F, indicating a lack of clean sediment cathode.   a  b Fig. 2 – Microstructure of powder using secondary electrons (a) and EDAX spectrum of powder products of electrolysis (b)  The elemental composition of the powders as set by mass - spectrometric analysis method. Results of mass spectrometric analysis and X-ray diffraction data con-firm the microanalysis of the presence of zirconium in the product and no other impurity phases. In the mass spectrum clearly recorded five peaks, which corre-sponds to the natural prevalence of zirconium, with the main peak corresponds to 90Zr.  4. CONCLUSION  Thus on the basis of the studies found the various factors on the electroreduction of zirconium. Thus, with increasing temperature of the electrolyte on current yield partially reduced.  This can be explained by increasing the intensity of the chemical interaction of metals with salt phase, the formation of reaction products and other factors. There-fore, there is an optimum temperature at which the least likely occurring secondary and indirect processes that reduce output by current, while maintaining con-stant other physic and chemical properties of the elec-trolyte. This temperature for each different salt mix-tures, in our case we can recommend temperatures of 580-650 ˚ C. Exit from current increases with increasing current density. The main reason for the significant difference between the output current from Faraday's law of elec-trolysis in molten salts are metal loss due to its dissolu-tion in the electrolyte or dispersion in the melt in the  TECHNOLOGY FEATURES AN ELECTROCHEMICAL… PROC. NAP2, 04NEA11 (2013)   04NEA11-3 case of the formation of loose sediments. Very high cur-rent density increases the voltage drop in the electro-lyte layer and increases power consumption. Moreover, with increasing cathode current density increases ac-cordingly and anode current density at the anode and the anode effect occurs that violates the normal course of electrolysis (in our experiments at high anodic cur-rent density observed effect). At high current densities also possible occurrence of side processes - selection of the cathode along with the base metal in the metal present in the electrolyte, such as alkaline Na or K. The optimal process parameters of electrolysis for substrates of different materials: і  (0,1 - 0,3) А/sm2, U  (2,8-3,0) V, Т  600-650 С (zirconium); і  (0,2-0,4) А/sm2, U  2,6 - 2,8 V, Т  600-650 С (brass), і = (0,3-0,45) А/sm2, U  2,7 -2,8V, Т  580-630 С (steel). Investigated the microstructure of powdered zirco-nium, calculated crystallite sizes that are roughly equal to 2 - 50 microns, depending on the conditions of elec-trolysis. Determined the elemental composition of the powder corresponding zirconium.    REFERENCES  1. V.M. Аzhazha, P.N. V’yuhov, G.P. Kovtun, I.M. Neklyudov, VANT 6, 3 (2004). 2. N.N. Pilipenko, VANT 2, 66 (2008). 3. A. Shevtsov, M. Zemlyanyi, A. Doroshevich, http://www.db.niss.gov.ua/docs/energy/116.htm. 4. L.P. Polyakova, E.H. Polyakov, P.T. Stangrit, Rasplavy 1, 54 (1991).  5. S.F. Katyshev, L.M. Teslyuk, Electrokhimija 45 No7, 884 (2009). 6. R.N. Savchuk, N.M. Komporishenko and A.A Omelchuk, Ukr. Chemistry J. 69 No3, 26 (2003).  

Technology Features an Electrochemical Obtain Powdered Zirconium

SocioEconomic Challenges Journal (Sumy State University)

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE  
NANOMATERIALS: APPLICATIONS AND PROPERTIES 
Vol. 2 No 4, 04NEA11(3pp) (2013) 
 
 
2304-1862/2013/2(4) 04NEA11(3) 04NEA11-1  2013 Sumy State University 
Technology Features an Electrochemical Obtain Powdered Zirconium 
 
Z.М. Protsenko* 
 
Sumy State Pedagogical University, 87, Romenska Str., 40001 Sumy, Ukraine,   
 
(Received 16 June 2013; published online 03 September 2013) 
 
The work is devoted to technology electrochemical obtain powder of zirconium ion fluoride melts (set-
ting parameters of the electrolysis method of washing powder Zr impurities from salt mixture components) 
on different substrates. Phase and element composition and cell size distribution of powdered zirconium 
was investigated. 
 
Keywords: Powdered Zirconium, Electrolysis, Phase and Elemental Composition. 
 
  PACS numbers: 81.15.-z, 81.40.Cd PACS number(s): 00.00.Хх, 00.00.Хх 
 
 
                                                          
* zoya.protsenko@i.ua  
1. INTRODUCTION 
 
Now there are several methods for preparing zirco-
nium in powder, and massive state. Zirconium is widely 
used in nuclear energy, space technology, electronics, 
chemical industry and other branches of engineering. 
Ability to use zirconium in many cases depends on its 
purity. For nuclear power to create structural reactor 
blocks them (shells of fuel elements fuel, ducted pipes) 
are requirements for purity zirconium a relatively oxy-
gen, nitrogen, carbon (less than 0.05, 0.006, 0.005 at.%, 
respectively). For example, in works [1, 2] paid atten-
tion to obtaining high-purity and nuclear-purity zirco-
nium. To obtain high-purity metals, including zirconi-
um, the authors of work [1] proposed the application at 
various stages of refining of complex chemical or physi-
cal and chemical methods. To obtain nuclear-pure zir-
conium and alloys based on zirconium with magnesium 
thermal or iodide zirconium devoted to the work [2]. 
For the reprocessing of spent nuclear fuel, promis-
ing electrochemical method for electron electroreduc-
tion Zr fluoride of salt melts. Although the problem 
electroreduction of Zr salt melts considerable attention 
in the work of domestic and foreign authors [2-6], there 
are still many unexplored and clarified points, so the 
subject study on the electroreduction of fluoride Zr al-
loys is important. 
The aim of this study was to establish the optimal 
process parameters of electrolysis, obtaining powdered 
Zr, washing it from impurities and establishment of 
phase and elemental composition and granule size dis-
tribution of powder product. 
 
2. EXPERIMENTAL МЕTHODIC 
 
For the electrolysis was elected two eutectic mix-
tures  based  on  NaF-ZrF4:  NaF  (50,5 ml.%) - ZrF4 
(49,5 mol.%), 500 оC and  NaF (59,5 ml.%)-ZrF4 (40.5 
ml.%), 512 оC. Anode served graphite was used as the 
cathode plate of copper, brass, bronze, zirconium, stain-
less steel. Electrolysis was carried out for 2-4 hours in 
the galvanic static mode under argon. Temperature 
was asked within 570-770 оC, cathode current density 
of 0.2 - 0.5 A/cm2. Purified from salt impurities by de-
cantation in hot water, acidified hydrochloric acid pow-
der residue analyzed by X-ray diffraction (DRON dif-
fractometer - 4.0 in К  radiation Cu) and  mass  spec-
trometry (mass spectrometer MS-7201) analysis. The 
elemental and granule composition of the product was 
determined by scanning microscope REMMA-102-02. 
 
3. EXPERIMENTAL RESULTS 
 
Selection to melt electrolysis caused by both physi-
cal and chemical properties of the salt mixture (rela-
tively high melting point, no volatility, resistance to 
heat, the solubility of zirconia in it), and associated 
with the possible use of these systems in nuclear pow-
er. The experiment was conducted in order to choose 
the material electrode - cathode, not corroded in the 
studied salt mixture is not formed from zirconium dep-
osition temperature of its chemical compounds. The 
important point was to establish the parameters of the 
process of electrolysis to produce dense precipitate of 
zirconium powder with minimal salt impurities mini-
mum loss (dissipation) powder in the melt and subse-
quent easy removal of it from the substrate.  
Dependence of mass increase cathode (for different 
materials) of the current density with a parabolic form, 
indicating the diffusion control process electroreduction 
zirconium.  
When choosing the optimum current density and 
the cathode material into account primarily mass of 
sediment (at the same time and temperature electroly-
sis), the content in the sediment of salt impurities, the 
density of sediment and the ease of its removal from 
the substrate. Note that in all cases the deposit on the 
substrate was in the form growths dendrites that are 
removed mechanically. As follows from the experi-
mental data, the best results are obtained when using 
as substrate zirconium (the largest daily gain, the 
smallest impurities including salt), but it was great 
complications in the removal of sediment from the sub-
strate, so we can recommend to use as a cathode sub-
strates, brass, or copper. In addition, based on experi-
mental data and Faraday's law was calculated output 
current for powdered zirconium, this value is 86% 
 Z.M. PROTSENKO PROC. NAP2, 04NEA11 (2013) 
 
 
04NEA11-2 
(cathode-zirconium), 80% (brass), 74% (steel). 
Reduced value of the output current can be ex-
plained by the partial loss of zirconium in the melt and 
in washing. 
Obtained and purified from salt impurities zirconia 
powder was analyzed by X-ray diffraction analysis to 
determine the phase composition of the product. For 
example, Figure 1 shows a fragment of the X-ray pat-
tern obtained on the substrate of zirconium. 
 
0
20
40
60
80
100
120
0 20 40 60 80 100
 
 2θ, degree 
 
Fig. 1 – X-ray pattern for powder product of electrolysis ob-
tain on zirconium substrate 
 
After decoding of radiographs, found that all the 
lines correspond to the same phase - the phase of zirco-
nium impurity phases were found, although the X-ray 
analysis reveals no trace. Similar results we obtained 
in the case of a substrate with brass. In Table 1 for ex-
ample the results of XRD analysis, the resulting pow-
der lined with brass. Found that all the lines corre-
spond to the phase of zirconia, but recorded each radio-
graph as several lines (on the background), which can 
be attributed to the phase of ZrO2, ie powder contained 
not a large percentage of impurity phase (less than 1%). 
 
Таble 1 – X-ray analysis of the electrolysis products (pow-
dered zirconium) on brass substrate 
 
№ 
Experimental data 
Таble data 
for Zr 
2θ, degree d, Å I, % d, Å I, % 
1 31,85 2,8096 54 2,780 33 
2 34,45 2,6033 51 2,573 32 
3 36,35 2,4714 100 2,459 100 
5 47,65 1,9084 47 1,894 17 
6 56,70 1,6234 50 1,616 17 
7 62,95 1,4764 46 1,463 18 
8 68,05 1,3777 45 1,368 18 
9 69,20 1,3576 41 1,350 12 
 
Elemental and granular size distribution of powder 
precipitate Zr was determined by X-ray microanalysis 
(PMA) and electron microscopy. Microstructure on Fig. 
2a clearly shows that dust does not have a clear crys-
talline structure, their size is (2 - 20) microns. On Fig. 
2b presents EDAX spectrum of powder products of elec-
trolysis, shot wave dispersion spectrometer. In the in-
set is represented the elemental composition (wt.%) 
zirconium powder precipitate corresponding Zr and 
doped elements K, Cl (artificially brought about during 
washing) and F, indicating a lack of clean sediment 
cathode. 
 
 
a 
 
b 
Fig. 2 – Microstructure of powder using secondary electrons 
(a) and EDAX spectrum of powder products of electrolysis (b) 
 
The elemental composition of the powders as set by 
mass - spectrometric analysis method. Results of mass 
spectrometric analysis and X-ray diffraction data con-
firm the microanalysis of the presence of zirconium in 
the product and no other impurity phases. In the mass 
spectrum clearly recorded five peaks, which corre-
sponds to the natural prevalence of zirconium, with the 
main peak corresponds to 90Zr. 
 
4. CONCLUSION 
 
Thus on the basis of the studies found the various 
factors on the electroreduction of zirconium. Thus, with 
increasing temperature of the electrolyte on current 
yield partially reduced.  
This can be explained by increasing the intensity of 
the chemical interaction of metals with salt phase, the 
formation of reaction products and other factors. There-
fore, there is an optimum temperature at which the 
least likely occurring secondary and indirect processes 
that reduce output by current, while maintaining con-
stant other physic and chemical properties of the elec-
trolyte. This temperature for each different salt mix-
tures, in our case we can recommend temperatures of 
580-650 ˚ C. 
Exit from current increases with increasing current 
density. The main reason for the significant difference 
between the output current from Faraday's law of elec-
trolysis in molten salts are metal loss due to its dissolu-
tion in the electrolyte or dispersion in the melt in the 
 TECHNOLOGY FEATURES AN ELECTROCHEMICAL… PROC. NAP2, 04NEA11 (2013) 
 
 
04NEA11-3 
case of the formation of loose sediments. Very high cur-
rent density increases the voltage drop in the electro-
lyte layer and increases power consumption. Moreover, 
with increasing cathode current density increases ac-
cordingly and anode current density at the anode and 
the anode effect occurs that violates the normal course 
of electrolysis (in our experiments at high anodic cur-
rent density observed effect). 
At high current densities also possible occurrence of 
side processes - selection of the cathode along with the 
base metal in the metal present in the electrolyte, such 
as alkaline Na or K. 
The optimal process parameters of electrolysis for 
substrates of different materials: і  (0,1 - 0,3) А/sm2, 
U  (2,8-3,0) V, Т  600-650 С (zirconium); і  (0,2-0,4) 
А/sm2, U  2,6 - 2,8 V, Т  600-650 С (brass), і = (0,3-
0,45) А/sm2, U  2,7 -2,8V, Т  580-630 С (steel). 
Investigated the microstructure of powdered zirco-
nium, calculated crystallite sizes that are roughly equal 
to 2 - 50 microns, depending on the conditions of elec-
trolysis. Determined the elemental composition of the 
powder corresponding zirconium. 
 
 
 
REFERENCES 
 
1. V.M. Аzhazha, P.N. V’yuhov, G.P. Kovtun, I.M. Neklyudov, 
VANT 6, 3 (2004). 
2. N.N. Pilipenko, VANT 2, 66 (2008). 
3. A. Shevtsov, M. Zemlyanyi, A. Doroshevich, 
http://www.db.niss.gov.ua/docs/energy/116.htm. 
4. L.P. Polyakova, E.H. Polyakov, P.T. Stangrit, Rasplavy 1, 
54 (1991).  
5. S.F. Katyshev, L.M. Teslyuk, Electrokhimija 45 No7, 884 
(2009). 
6. R.N. Savchuk, N.M. Komporishenko and A.A Omelchuk, 
Ukr. Chemistry J. 69 No3, 26 (2003). 
 


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Technology Features an Electrochemical Obtain Powdered Zirconium

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