Investigation of Various LiCl Waste Salt Purification Technologies

International Nuclear Information System (INIS)

Yung-Zun Cho; Hee-Chul Yang; Han-Soo Lee; In-Tae Kim

2008-01-01

Various purification research of LiCl waste molten salt generated from electroreduction process were tested. The purification of the LiCl waste salt very important in a various aspects, where the purification means separation of cesium and strontium form LiCl salt melts. In this study, for the separation of cesium and strontium from LiCl salt melts, precipitant agent addition techniques such as sulfate and carbonate addition method and, as a new attempt, zone freezing technique for concentration of cesium and strontium elements was investigated. As a results of this research, only strontium was carbonated by reaction with Li 2 CO 3 (cesium did not react with Li 2 CO 3 ). In case of sulfate addition method, both cesium and strontium were converted into their sulfate that is Cs 2 S 2 O 6 and SrSO 4 and maximum sulfate efficiency of cesium and strontium were about 72% and 95%, respectively. Cesium and strontium involved in LiCl molten salt could be concentrated in the molten salt by using zone freezing method. (authors)

Saturated steams pressure of HfCl4-KCl molten mixtures

International Nuclear Information System (INIS)

Salyulev, A.B.; Smirnov, M.V.; Kudyakov, V.Ya.

1980-01-01

A bellows null pressure gauge and the dynamic method were used to measure the total and partial pressures of saturated vapors of individual components of molten HfCl 4 -KCl mixtures, as a function of temperature (260 to 1000 deg C) and composition (1.9 to 64.3 mol.% HfCl 4 ). Empirical equations expressing the relationship between pressure and temperature are presented. It is shown that in molten mixtures of hafnium tetrachloride with chlorides of alkaline metals its partial pressure dramatically increases when potassium chloride substitutes for cesium chloride

Density of molten salt Mixtures of eutectic LiCl-KCl containing UCl{sub 3}, CeCl{sub 3}, or LaCl{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Zhang, C.; Simpson, M. F. [Dept. of Metallurgical Engineering, University of Utah, Salt Lake City (United States)

2017-06-15

Densities of molten salt mixtures of eutectic LiCl-KCl with UCl{sub 3}, CeCl{sub 3}, or LaCl{sub 3} at various concentrations (up to 13 wt%) were measured using a liquid surface displacement probe. Linear relationships between the mixture density and the concentration of the added salt were observed. For LaCl{sub 3} and CeCl{sub 3}, the measured densities were signifcantly higher than those previously reported from Archimedes’ method. In the case of LiCl-KCl-UCl{sub 3}, the data ft the ideal mixture density model very well. For the other salts, the measured densities exceeded the ideal model prediction by about 2%.

Voltammetry of uranyl chloride in the LiCl - KCl eutectic

International Nuclear Information System (INIS)

Fondanaiche, J.C.

1965-01-01

Spent UO 2 - PuO 2 fuels can be reprocessed in a molten salt media. Uranium dioxide can easily be dissolved as UO 2 Cl 2 in a molten salt bath using chlorine gas. A study of quantitative analysis of an uranyl chloride solution in the LiCl-KCl eutectic at 400 C has been performed here using voltammetry (a large area-graphite indicator electrode has been employed). The precision which is obtained is around 6 per cent for concentrations below 10 -2 M. Precision decreases slightly for more concentrated solutions. The study of polarization curves allowed to give a reduction mechanism for the UO 2 ++ ion. For dilute solutions, this reduction proceeds through the UO 2 + ion. But interpretation of current-potential curves is made difficult by the dismutation reaction of the UO 2 ion and by the fact that the surface of the indicator electrode is not renewed. (author) [fr

Saturated steams pressure of HfCl/sub 4/-KCl molten mixtures

Energy Technology Data Exchange (ETDEWEB)

Salyulev, A B; Smirnov, M V; Kudyakov, V Ya [AN SSSR, Sverdlovsk. Inst. Ehlektrokhimii

1980-02-01

A bellows null pressure gauge and the dynamic method were used to measure the total and partial pressures of saturated vapors of individual components of molten HfCl/sub 4/-KCl mixtures, as a function of temperature (260 to 1000 deg C) and composition (1.9 to 64.3 mol.% HfCl/sub 4/). Empirical equations expressing the relationship between pressure and temperature are presented. It is shown that in molten mixtures of hafnium tetrachloride with chlorides of alkaline metals its partial pressure dramatically increases when potassium chloride substitutes for cesium chloride.

Fluorescence Resonance Energy Transfer of the Tb(III)-Nd(III) Binary System in Molten LiCl-KCl Eutectic Salt

Energy Technology Data Exchange (ETDEWEB)

Kim, B. Y. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yun, J. I. [KAIST, Daejeon (Korea, Republic of)

2015-05-15

The lanthanides act as a neutron poison in nuclear reactor with large neutron absorption cross section. For that reason, very low amount of lanthanides is required in the recovered U/TRU ingot product from pyrochemical process. In view of that, the investigation of thermodynamic properties and chemical behaviors of lanthanides in molten chloride salt are necessary to estimate the performance efficiency of pyrochemical process. However, there are uncertainties about knowledge and understanding of basic mechanisms in pyrochemical process, such as chemical speciation and redox behaviors due to the lack of in-situ monitoring methods for high temperature molten salt. The spectroscopic analysis is one of the probable techniques for in-situ qualitative and quantitative analysis. Recently, a few fluorescence spectroscopic measurements on single lanthanide element in molten LiCl-KCl eutectic have been investigated. The fluorescence intensity and the fluorescence lifetime of Tb(III) were decreased as increasing the concentration of Nd(III), demonstrating collisional quenching between donor ions and acceptor ions. The Forster distance (..0) of Tb(III)-Nd(III) binary system in molten LiCl-KCl eutectic was determined in the specific range of .... (0.1-1.0) and .. (1.387-1.496)

Study of an F center in molten KCl

International Nuclear Information System (INIS)

Parrinello, M.; Rahman, A.

1983-05-01

It is shown that a discretized version of Feynman's path integral provides a convenient tool for the numerical investigation of the properties of an electron solvated in molten KCl. The binding energy and the pair correlation functions are calculated. The local structure around the solute electron appears to be different from that of an F center in the solid

Stabilization of molten salt materials using metal chlorides for solar thermal storage.

Science.gov (United States)

Dunlop, T O; Jarvis, D J; Voice, W E; Sullivan, J H

2018-05-29

The effect of a variety of metal-chlorides additions on the melting behavior and thermal stability of commercially available salts was investigated. Ternary salts comprised of KNO 3, NaNO 2, and NaNO 3 were produced with additions of a variety of chlorides (KCl, LiCl, CaCl 2 , ZnCl 2 , NaCl and MgCl 2 ). Thermogravimetric analysis and weight loss experiments showed that the quaternary salt containing a 5 wt% addition of LiCl and KCl led to an increase in short term thermal stability compared to the ternary control salts. These additions allowed the salts to remain stable up to a temperature of 630 °C. Long term weight loss experiments showed an upper stability increase of 50 °C. A 5 wt% LiCl addition resulted in a weight loss of only 25% after 30 hours in comparison to a 61% loss for control ternary salts. Calorimetry showed that LiCl additions allow partial melting at 80 °C, in comparison to the 142 °C of ternary salts. This drop in melting point, combined with increased stability, provided a molten working range increase of almost 100 °C in total, in comparison to the control ternary salts. XRD analysis showed the oxidation effect of decomposing salts and the additional phase created with LiCl additions to allow melting point changes to occur.

Molten salt corrosion behavior of structural materials in LiCl-KCl-UCl3 by thermogravimetric study

Science.gov (United States)

Rao, Ch Jagadeeswara; Ningshen, S.; Mallika, C.; Mudali, U. Kamachi

2018-04-01

The corrosion resistance of structural materials has been recognized as a key issue in the various unit operations such as salt purification, electrorefining, cathode processing and injection casting in the pyrochemical reprocessing of spent metallic nuclear fuels. In the present work, the corrosion behavior of the candidate materials of stainless steel (SS) 410, 2.25Cr-1Mo and 9Cr-1Mo steels was investigated in molten LiCl-KCl-UCl3 salt by thermogravimetric analysis under inert and reactive atmospheres at 500 and 600 °C, for 6 h duration. Insignificant weight gain (less than 1 mg/cm2) in the inert atmosphere and marginal weight gain (maximum 5 mg/cm2) in the reactive atmosphere were observed at both the temperatures. Chromium depletion rates and formation of Cr-rich corrosion products increased with increasing temperature of exposure in both inert and reactive atmospheres as evidenced by SEM and EDS analysis. The corrosion attack by LiCl-KCl-UCl3 molten salt, under reactive atmosphere for 6 h duration was more in the case of SS410 than 9Cr-1Mo steel followed by 2.25Cr-1Mo steel at 500 °C and the corrosion attack at 600 °C followed the order: 9Cr-1Mo steel >2.25Cr-1Mo steel > SS410. Outward diffusion of the minor alloying element, Mo was observed in 9Cr-1Mo and 2.25Cr-1Mo steels at both temperatures under reactive atmosphere. Laser Raman spectral analysis of the molten salt corrosion tested alloys under a reactive atmosphere at 500 and 600 °C for 6 h revealed the formation of unprotected Fe3O4 and α-as well as γ-Fe2O3. The results of the present study facilitate the selection of structural materials for applications in the corrosive molten salt environment at high temperatures.

Direct reduction of uranium oxide(U3O8) by Li metal and U-metal(Fe, Ni) alloy formation in molten LiCl medium

International Nuclear Information System (INIS)

Cho, Young Hwan; Kim, Tack Jin; Choi, In Kyu; Kim, Won Ho; Jee, Kwang Yong

2004-01-01

Molten salt based electrochemical processes are proposed as a promising method for the future nuclear programs and more specifically for spent fuel processing. The lithium reduction has been introduced to convert actinide oxides into corresponding actinide metal by using lithium metal as a reductant in molten LiCl medium. We have applied similar lab-scale experiments to reduce uranium oxide in an effort to gain additional information on rates and mechanisms

Study of an F center in molten KCl

Energy Technology Data Exchange (ETDEWEB)

Parrinello, M.; Rahman, A.

1983-05-01

It is shown that a discretized version of Feynman's path integral provides a convenient tool for the numerical investigation of the properties of an electron solvated in molten KCl. The binding energy and the pair correlation functions are calculated. The local structure around the solute electron appears to be different from that of an F center in the solid.

In-line monitoring of an oxide ion in LiCl molten salt using a YSZ based oxide ion selective electrode

International Nuclear Information System (INIS)

Cho, Young Hwan; Jeon, Jong Seon; Yeon, Jei Won; Choi, In Kyu; Kim, Won Ho

2004-01-01

The electrode potential characteristics of a YSZ based membrane metal oxide electrode have been studied in molten LiCl at 700 .deg. C by the potentiometric method. The electrode exhibited a good potential response to log[O 2 ] and data reproducibility. The calibration plot (potential vs. log[O 2 ] was found to be linear, obeying the nernst equation. The electrode potential showed a good reversibility corresponding to increase/decrease of the oxide ion present in the molten LiCl. The physical and chemical durability appeared to be sound after several repeated uses, resulting in reproducible results. However, 'the proposed electrode' failed when metallic Li was present in the melt

Electrochemical Behavior of LiBr, LiI, and Li2Se in LiCl Molten Salt

International Nuclear Information System (INIS)

Choi, In Kyu; Do, Jae Bum; Hong, Sun Seok; Seo, Chung Seok

2006-03-01

The effect of fission products on the electrolytic reduction of uranium oxide has been studied. It has been reported that volatile fission products, such as Br, I, and Se, react with Li metal which is a reductant in the process to give LiBr, LiI, and Li 2 Se. These compounds are dissociated as corresponding anions and cations in the LiCl molten salt at 650 .deg. C. In this experiment, oxidation and reduction reaction of 3wt% of each compound in LiCl molten salt were investigated by cyclic voltammetry. For LiBr, redox reactions of cation and anion were reversible, while redox reactions of Li + and I - were irreversible. For Li 2 Se, about half of the produced Li metal was disappeared at the cathode and two anodic current curves were appeared. After the cyclic voltammetric measurements for each compound, chronopotentiometric experiment was carried out for one hour with 100 - 400 mA. After the electrolysis, no compounds gave Li metal in the porous MgO filter in which Li metal was produced at the cathode. However, LiCl salt was covered with Br 2 for LiBr electrolysis. Dark red color of Br 2 was easily removed by water. For LiI electrolysis, salt gave black color and I 2 was deposited on the Pt anode. For Li 2 Se electrolysis, black fine powders were precipitated in the salt. After the separation and dryness of the precipitates, it was analyzed with XRD and it turned out PtSe 2 . From the electrochemical experimental results, it was concluded that these compounds may affect the electrolytic reduction process of uranium oxide in the spent fuel

Investigation of the evaporation of rare earth chlorides in a LiCl-KCl molten salt

International Nuclear Information System (INIS)

Sung Bin Park; Dong Wook Cho; Moon Sik Woo; Sung Chan Hwang; Young Ho Kang; Jeong Guk Kim; Hansoo Lee

2011-01-01

Uranium dendrites which were deposited at a solid cathode of an electrorefiner contained a certain amount of salts. These salts should be removed for the recovery of pure metal using a cathode processor. In the uranium deposits from the electrorefining process, there are actinide chlorides and rare earth chlorides in addition to uranium chloride in the LiCl-KCl eutectic salt. The evaporation behaviors of the actinides and rare earth chlorides in the salts should be investigated for the removal of salts in the deposits. Experiments on the salt evaporation of rare earth chlorides in a LiCl-KCl eutectic salt were carried out. Though the vapor pressures of the rare earth chlorides were lower than those of the LiCl and KCl, the rare earth chlorides were co-evaporized with the LiCl-KCl eutectic salt. The Hertz-Langmuir relation was applied for this evaporation, and also the evaporation rates of the salt were obtained. The co-evaporation of the rare earth chlorides and LiCl-KCl eutectic were also discussed. (author)

Electrochemical Behavior of La on Liquid Bi electrode in LiCl-KCl molten salt

Energy Technology Data Exchange (ETDEWEB)

Kim, Beom Kyu; Han, Hwa Jeong; Park, Byung Gi [Soonchunyang University, Asan (Korea, Republic of)

2016-05-15

Pyroprocessing technology aims to achieve a grouped and efficiently separation of all actinide for recycling with a sufficient decontamination of fission products generating the minimum. The main steps of the pyroprocess is electrowinning process, where the remaining elements in a molten salt after electrorifinning process. That process is U, MAs are concurrently recovered at the liquid metal. Recently, a study of the liquid metal and molten salt using an electrochemical is carried out in a variety of fields. However, there is deficient information about the electrode reaction of lanthanide and actinide on the liquid bismuth metal electrodes. In this paper, the electrochemical behavior of La(III), with liquid bismuth was investigated by the electrochemical method. The aim of this study is to investigate the electrochemical behavior of lanthanum or neodymium among lanthanides in molten LiCl-KCl salt at liquid metal bismuth electrode cyclic voltammetry and derive the thermochemical properties. The electrochemical behavior of La was studied in LiCl-KCl-LaCl{sub 3} molten salts using electrochemical techniques Cyclic Voltammetry on liquid Bi electrodes at 773K. During the process of cyclic voltammetry electrolysis, intermetallic compound were observed of La, Lax-Biy, Li-Bi. The diffusion coefficient of La was measured by cyclic voltemmetry and was found to be 8.18x10{sup -5}cm{sup 2}/s.

Raman spectroscopic study of the oxidation state of Eu in molten LiCl-KCl

Energy Technology Data Exchange (ETDEWEB)

Park, Seung; Yun, Jong-Il [KAIST, Daejeon(Korea, Republic of)

2016-10-15

Spectroscopy can provide high reliability for the quantitative analysis of such system. The molar absorptivity of Eu(II) at 325 nm is reported as about 1645 M{sup -1}cm{sup -1}, which is too high to apply to higher concentration. A high-temperature Raman spectroscopy has been set and employed for analyzing the molecular structure and coordination complex and investigating the oxidation state of europium in molten LiCl-KCl. Europium can be present in divalent state while many other lanthanides exist in trivalent state. The thermodynamic properties of europium ions have been studied using electrochemical methods, spectroscopic methods, and EPR technique. Although there has been discrepancy of the reduced amount of europium in previous works, the majority of Eu(III) is thought to be reduced to Eu(II) in molten LiCl-KCl spontaneously at relatively low concentration (< 7.5 × 10{sup -4} M). Raman spectroscopy was employed to investigate the oxidation state of EuClx in LiCl-KCl at 500 .deg. C. The Raman scattering results suggest the majority of trivalent europium is reduced to divalent state with the composition change by vaporization. The Raman bands show highly asymmetric structure, quite different from regular octahedral structure.

Partitioning of actinides and fission products using molten salt electrorefining process

International Nuclear Information System (INIS)

Barbero, Jose A.; Wiesztort, Andres; Azcona, Alejandra; Bollini, Edgardo; Forchetti, Alberto; Orce, Alan

1999-01-01

Electrorefining is the key step of pyrometallurgical processing for separating actinides from fission products. In this work, the electrorefining process is carried out in a electrorefining cell that contains molten salts (49% LiCl- 51% KCL) floating on a liquid cadmium. The cell is operated under an inert atmosphere at 500 degree C. In this work we describe in detail the construction of the cell and the way of operation

Application of the rotating cylinder electrode in molten LiCl-KCl eutectic containing uranium(III)- and magnesium(II)-chloride

Energy Technology Data Exchange (ETDEWEB)

Rappleye, Devin, E-mail: rappleye1@llnl.gov; Simpson, Michael F.

2017-04-15

The application of the rotating cylinder electrode (RCE) to molten LiCl-KCl eutectic mixtures for electroanalytical measurements is presented. This enabled the measurement of the limiting current which was observed to follow a linear trend with the rotational rate raised to 0.64–0.65 power on average, which closely agrees with existing RCE mass-transfer correlations. This is the first publication of electroanalytical RCE measurements in LiCl-KCl eutectic based molten salt mixtures, to our knowledge. These measurements were made in mixtures of molten LiCl-KCl eutectic containing UCl{sub 3} and MgCl{sub 2}. Kinetic parameters were calculated for Mg{sup 2+} in LiCl-KCl eutectic. The exchange current density (i{sub o}) of Mg{sup 2+} deposition varied with mole fraction (x) according to i{sub o}(A cm{sup −2}) = 1.64x{sup 0.689}. The parameters from RCE measurements were also applied in an electrochemical co-deposition model entitled DREP to detect and predict the deposition rate of U and Mg. DREP succeeded in detecting the co-deposition of U and Mg, even when Mg constituted less than 0.5 wt% of the deposit.

Electrical Conductivity of Molten DyCl3-NaCl and DyCl3-KCl Systems: An Approach to Structural Interpretations of Rare Earth Chloride Melts

Science.gov (United States)

Iwadate, Yasuhiko; Ohkubo, Takahiro

2017-11-01

Electrical conductivities (κs) of molten DyCl3-NaCl and DyCl3-KCl systems were estimated by measuring the impedances of each mixture melt at any temperature and/or frequency. The molar volumes (Vms) were measured by dilatometry and represented as a polynomial empirical equation of temperature and composition. Due to both the properties, the molar conductivities (Λms) were calculated and their temperature and/or composition dependences were discussed from the standpoint of structural features as well. The κs increased curvilinearly with increasing temperature across the whole composition ranges. This trend was also applied to the Λms which was fitted by an Arrhenius-type equation. The relationship of Λms with melt composition was studied and the Λms were found to decrease with increasing composition of DyCl3. These findings were interpreted based on the results of structural science so far reported, and finally, the relationship between Λms and the structures of pure rare earth chloride melts was discussed.

Chemical interactions and thermodynamic studies in aluminum alloy/molten salt systems

Science.gov (United States)

Narayanan, Ramesh

The recycling of aluminum and aluminum alloys such as Used Beverage Container (UBC) is done under a cover of molten salt flux based on (NaCl-KCl+fluorides). The reactions of aluminum alloys with molten salt fluxes have been investigated. Thermodynamic calculations are performed in the alloy/salt flux systems which allow quantitative predictions of the equilibrium compositions. There is preferential reaction of Mg in Al-Mg alloy with molten salt fluxes, especially those containing fluorides like NaF. An exchange reaction between Al-Mg alloy and molten salt flux has been demonstrated. Mg from the Al-Mg alloy transfers into the salt flux while Na from the salt flux transfers into the metal. Thermodynamic calculations indicated that the amount of Na in metal increases as the Mg content in alloy and/or NaF content in the reacting flux increases. This is an important point because small amounts of Na have a detrimental effect on the mechanical properties of the Al-Mg alloy. The reactions of Al alloys with molten salt fluxes result in the formation of bluish purple colored "streamers". It was established that the streamer is liquid alkali metal (Na and K in the case of NaCl-KCl-NaF systems) dissipating into the melt. The melts in which such streamers were observed are identified. The metal losses occurring due to reactions have been quantified, both by thermodynamic calculations and experimentally. A computer program has been developed to calculate ternary phase diagrams in molten salt systems from the constituting binary phase diagrams, based on a regular solution model. The extent of deviation of the binary systems from regular solution has been quantified. The systems investigated in which good agreement was found between the calculated and experimental phase diagrams included NaF-KF-LiF, NaCl-NaF-NaI and KNOsb3-TINOsb3-LiNOsb3. Furthermore, an insight has been provided on the interrelationship between the regular solution parameters and the topology of the phase

Studies of the effects of TiCl3 in LiBH4/CaH2/TiCl3 reversible hydrogen storage system

International Nuclear Information System (INIS)

Liu Dongan; Yang Jun; Ni Jun; Drews, Andy

2012-01-01

Highlights: ► We systematically studied the effects of TiCl 3 in LiBH 4 /CaH 2 /TiCl 3 hydrogen storage system. ► It is found that adding 0.25 TiCl 3 produces fully reversible hydrogen absorption and desorption and a lower desorption temperature. ► LiCl experiences four different states, i.e. “formed-solid solution-molten solution-precipitation”, in the whole desorption process of the system. ► The incorporation of LiCl into LiBH 4 forms more viscous molten LiBH 4 ·LiCl, leading to fast kinetics. ► The precipitation and re-incorporation of LiCl into LiBH 4 lead to a fully reversible complex hydrogen storage system. - Abstract: In the present study, the effects of TiCl 3 on desorption kinetics, absorption/desorption reversibility, and related phase transformation processes in LiBH 4 /CaH 2 /TiCl 3 hydrogen storage system was studied systematically by varying its concentration (x = 0, 0.05, 0.15 and 0.25). The results show that LiCl forms during ball milling of 6LiBH 4 /CaH 2 /xTiCl 3 and that as temperature increases, o-LiBH 4 transforms into h-LiBH 4 , into which LiCl incorporates, forming solid solution of LiBH 4 ·LiCl, which melts above 280 °C. Molten LiBH 4 ·LiCl is more viscous than molten LiBH 4 , preventing the clustering of LiBH 4 and the accompanied agglomeration of CaH 2 , and thus preserving the nano-sized phase arrangement formed during ball milling. Above 350 °C, the molten solution LiBH 4 ·LiCl further reacts with CaH 2 , precipitating LiCl. The main hydrogen desorption reaction is between molten LiBH 4 ·LiCl and CaH 2 and not between molten LiBH 4 and CaH 2 . This alters the hydrogen reaction thermodynamics and lowers the hydrogen desorption temperature. In addition, the solid–liquid nano-sized phase arrangement in the nano-composites improves the hydrogen reaction kinetics. The reversible incorporation/precipitation of LiCl at the hydrogen reaction temperature and during temperature cycling makes the 6LiBH 4 /CaH 2 /0.25TiCl 3

First principles study of the thermodynamic and kinetic properties of U in an electrorefining system using molybdenum cathode and LiCl-KCl eutectic molten salt

International Nuclear Information System (INIS)

Kwon, Choah; Kang, Joonhee; Kang, Woojong; Kwak, Dohyun; Han, Byungchan

2016-01-01

Using first principles density functional theory (DFT) calculations we obtain thermodynamic and kinetic properties of U in an electrorefining process for spent nuclear fuels using a LiCl-KCl eutectic molten salt and Mo as a cathode. The thermodynamic stability of electrodeposited U from the molten salt onto the Mo(110) surface electrode is evaluated by activity coefficients as function of surface coverages of U and Cl. Additionally, ab-initio molecular dynamic simulations combined with the Stokes-Einstein-Sutherland relation enables us to calculate the viscosity of the LiCl-KCl eutectic molten salt. Our results well agree with previously reported experimental data endorsing the credibility. Based on our atomic-level mechanical understanding we propose that an accurate computational model system incorporating the electrochemical conditions of the electrorefining process essential for the purpose of establishing thermodynamic and kinetic database of U, otherwise critical deviations are inevitable. More interestingly, the effect of coadsorption of Cl with U on the Mo(110) surface plays a key role in stabilizing electrodeposited U on the cathode. Our approach can be useful for validating published experimental database and for identifying key factors guiding a rational design of highly efficient electrorefining system for spent nuclear fuels, and thus reducing high-level radioactive nuclear wastes.

Electrodeposition of Al-Ta alloys in NaCl-KCl-AlCl{sub 3} molten salt containing TaCl{sub 5}

Energy Technology Data Exchange (ETDEWEB)

Sato, Kazuki; Matsushima, Hisayoshi; Ueda, Mikito, E-mail: mikito@eng.hokudai.ac.jp

2016-12-01

Highlights: • Electrodeposition of Al-Ta alloys in an AlCl{sub 3}-NaCl-KCl-TaCl{sub 5} melt was carried out. • We were obtained 72 at% Ta-Al alloy at 0.3 V. • Amorphous Ta-Al was formed in high Ta concentration. - Abstract: To form Al-Ta alloys for high temperature oxidation resistance components, molten salt electrolysis was carried out in an AlCl{sub 3}-NaCl-KCl melt containing TaCl{sub 5} at 423 K. The voltammogram showed two cathodic waves at 0.45 V and 0.7 V vs. Al/Al(III), which may correspond to reduction from Ta(V) to Ta(III) and from Ta(III) to tantalum metal, respectively. Electrodeposits of Al and Ta were obtained in the range from −0.05 to 0.3 V and the highest concentration of Ta in the electrodeposit was 72 at% at 0.3 V. With increasing Ta content in the alloy, the morphology of the electrodeposits became powdery and the particle size smaller.

Development of High-Temperature Transport System for Molten Salt in Pyroprocessing

International Nuclear Information System (INIS)

Lee, Sung Ho; Kim, In Tae; Park, Sung Bin

2014-01-01

The electrorefining process, which is a key process in pyroprocessing, is composed of two parts, electrorefining to deposit a uranium with a solid cathode and electrowinning to co-deposit TRU and RE with a liquid cadmium cathode (LCC). As the electrorefining operation proceedes, TRU and RE are accumulated in electrolyte LiCl-KCl salt, and after the electrorefining process, the molten salt used in an electrorefining reactor should by transported to the next process, the electrowinning process, to recover U/TRU/RE; Thus, a molten salt transfer system by suction is now being developed. An apparatus for suction transport experiments was designed and constructed for the development of high- temperature molten salt transport technology. Suction transport experiments were performed using LiC-KCl eutectic salt. The feasibility of pyro-reprocessing has been demonstrated through many laboratory-scale experiments. In pyroprocessing, a eutectic LiCl-KCl salt was used as a liquid elextrolyte for a recovery of actinides. However, reliable transport technologies for these high temperature liquids have not yet been developed. A preliminary study on high-temperature transport technology for molten salt by suction is now being carried out. In this study, three different salt transport technologies (gravity, suction pump, and centrifugal pump) were investigated to select the most suitable method for molten salt transport. An apparatus for suction transport experiments was designed and installed for the development of high-temperature molten salt transport technology. Basic preliminary suction transport experiments were carried out using the prepared LiC-KCl eutectic salt at 500 .deg. C to observe the transport behavior of LiCl-KCl molten salt. In addition, a PRIDE salt transport system was designed and installed for an engineering-scale salt transport demonstration. Several types of suction transport experiments using molten salt (LiCl-KCl eutectics) for the development of a high

Development of High-Temperature Transport System for Molten Salt in Pyroprocessing

Energy Technology Data Exchange (ETDEWEB)

Lee, Sung Ho; Kim, In Tae; Park, Sung Bin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

The electrorefining process, which is a key process in pyroprocessing, is composed of two parts, electrorefining to deposit a uranium with a solid cathode and electrowinning to co-deposit TRU and RE with a liquid cadmium cathode (LCC). As the electrorefining operation proceedes, TRU and RE are accumulated in electrolyte LiCl-KCl salt, and after the electrorefining process, the molten salt used in an electrorefining reactor should by transported to the next process, the electrowinning process, to recover U/TRU/RE; Thus, a molten salt transfer system by suction is now being developed. An apparatus for suction transport experiments was designed and constructed for the development of high- temperature molten salt transport technology. Suction transport experiments were performed using LiC-KCl eutectic salt. The feasibility of pyro-reprocessing has been demonstrated through many laboratory-scale experiments. In pyroprocessing, a eutectic LiCl-KCl salt was used as a liquid elextrolyte for a recovery of actinides. However, reliable transport technologies for these high temperature liquids have not yet been developed. A preliminary study on high-temperature transport technology for molten salt by suction is now being carried out. In this study, three different salt transport technologies (gravity, suction pump, and centrifugal pump) were investigated to select the most suitable method for molten salt transport. An apparatus for suction transport experiments was designed and installed for the development of high-temperature molten salt transport technology. Basic preliminary suction transport experiments were carried out using the prepared LiC-KCl eutectic salt at 500 .deg. C to observe the transport behavior of LiCl-KCl molten salt. In addition, a PRIDE salt transport system was designed and installed for an engineering-scale salt transport demonstration. Several types of suction transport experiments using molten salt (LiCl-KCl eutectics) for the development of a high

Investigation of residual anode material after electrorefining uranium in molten chloride salt

Energy Technology Data Exchange (ETDEWEB)

Rose, M.A., E-mail: marose@anl.gov [Department of Nuclear Engineering, Purdue University, West Lafayette, IN, 47907 (United States); Nuclear Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Williamson, M.A.; Willit, J. [Nuclear Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2015-12-15

A buildup of material at uranium anodes during uranium electrorefining in molten chloride salts has been observed. Potentiodynamic testing has been conducted using a three electrode cell, with a uranium working electrode in both LiCl/KCl eutectic and LiCl each containing ∼5 mol% UCl{sub 3}. The anodic current response was observed at 50° intervals between 450 °C and 650 °C in the eutectic salt. These tests revealed a buildup of material at the anode in LiCl/KCl salt, which was sampled at room temperature, and analyzed using ICP-MS, XRD and SEM techniques. Examination of the analytical data, current response curves and published phase diagrams has established that as the uranium anode dissolves, the U{sup 3+} ion concentration in the diffusion layer surrounding the electrode rises precipitously to levels, which may at low temperatures exceed the solubility limit for UCl{sub 3} or in the case of the eutectic salt for K{sub 2}UCl{sub 5}. The reduction in current response observed at low temperature in eutectic salt is eliminated at 650 °C, where K{sub 2}UCl{sub 5} is absent due to its congruent melting and only simple concentration polarization effects are seen. In LiCl similar concentration effects are seen though significantly longer time at applied potential is required to effect a reduction in the current response as compared to the eutectic salt.

The role of correlations in the determination of the transport properties of LaCl_3 in high temperature molten eutectic LiCl-KCl

International Nuclear Information System (INIS)

Samin, Adib; Wu, Evan; Zhang, Jinsuo

2017-01-01

It is important to develop an accurate assessment of fundamental data of lanthanides in high temperature molten salts to enable an efficient application of pyroprocessing. This requires a careful consideration of uncertainties in the reported results. In this study, cyclic voltammetry (CV) tests of LaCl_3 in KCl-LiCl molten salt were conducted at low concentration levels in the molten salt at 723 K and at several scan rates. The CV signals were subsequently analyzed through the conventional CV analysis and using a BET-based model through a nonlinear least-squares fitting procedure. It was determined that the parameters of the model were strongly correlated and the support plane procedure was implemented to assign joint confidence intervals for the diffusivity of lanthanum. Accounting for the correlations led to a significant increase in the uncertainty of the reported diffusivity which led to better agreement with the literature. Accounting for the correlations may be important for higher concentration levels.

Studies of the effects of TiCl{sub 3} in LiBH{sub 4}/CaH{sub 2}/TiCl{sub 3} reversible hydrogen storage system

Energy Technology Data Exchange (ETDEWEB)

Liu Dongan [Ford Motor Company, Research and Advanced Engineering, MD 1170/RIC, Dearborn, MI 48121 (United States); Department of Mechanical Engineering, University of Michigan, 1023 H. H. Dow Building 2350 Hayward Street, Ann Arbor, MI 48109-2125 (United States); Yang Jun, E-mail: jyang27@ford.com [Ford Motor Company, Research and Advanced Engineering, MD 1170/RIC, Dearborn, MI 48121 (United States); Ni Jun [Department of Mechanical Engineering, University of Michigan, 1023 H. H. Dow Building 2350 Hayward Street, Ann Arbor, MI 48109-2125 (United States); Drews, Andy [Ford Motor Company, Research and Advanced Engineering, MD 1170/RIC, Dearborn, MI 48121 (United States)

2012-02-15

Highlights: Black-Right-Pointing-Pointer We systematically studied the effects of TiCl{sub 3} in LiBH{sub 4}/CaH{sub 2}/TiCl{sub 3} hydrogen storage system. Black-Right-Pointing-Pointer It is found that adding 0.25 TiCl{sub 3} produces fully reversible hydrogen absorption and desorption and a lower desorption temperature. Black-Right-Pointing-Pointer LiCl experiences four different states, i.e. 'formed-solid solution-molten solution-precipitation', in the whole desorption process of the system. Black-Right-Pointing-Pointer The incorporation of LiCl into LiBH{sub 4} forms more viscous molten LiBH{sub 4}{center_dot}LiCl, leading to fast kinetics. Black-Right-Pointing-Pointer The precipitation and re-incorporation of LiCl into LiBH{sub 4} lead to a fully reversible complex hydrogen storage system. - Abstract: In the present study, the effects of TiCl{sub 3} on desorption kinetics, absorption/desorption reversibility, and related phase transformation processes in LiBH{sub 4}/CaH{sub 2}/TiCl{sub 3} hydrogen storage system was studied systematically by varying its concentration (x = 0, 0.05, 0.15 and 0.25). The results show that LiCl forms during ball milling of 6LiBH{sub 4}/CaH{sub 2}/xTiCl{sub 3} and that as temperature increases, o-LiBH{sub 4} transforms into h-LiBH{sub 4}, into which LiCl incorporates, forming solid solution of LiBH{sub 4}{center_dot}LiCl, which melts above 280 Degree-Sign C. Molten LiBH{sub 4}{center_dot}LiCl is more viscous than molten LiBH{sub 4}, preventing the clustering of LiBH{sub 4} and the accompanied agglomeration of CaH{sub 2}, and thus preserving the nano-sized phase arrangement formed during ball milling. Above 350 Degree-Sign C, the molten solution LiBH{sub 4}{center_dot}LiCl further reacts with CaH{sub 2}, precipitating LiCl. The main hydrogen desorption reaction is between molten LiBH{sub 4}{center_dot}LiCl and CaH{sub 2} and not between molten LiBH{sub 4} and CaH{sub 2}. This alters the hydrogen reaction thermodynamics and

The role of correlations in the determination of the transport properties of LaCl{sub 3} in high temperature molten eutectic LiCl-KCl

Energy Technology Data Exchange (ETDEWEB)

Samin, Adib; Wu, Evan; Zhang, Jinsuo [The Ohio State Univ., Columbus, OH (United States). Dept. of Mechanical and Aerospace Engineering

2017-10-01

It is important to develop an accurate assessment of fundamental data of lanthanides in high temperature molten salts to enable an efficient application of pyroprocessing. This requires a careful consideration of uncertainties in the reported results. In this study, cyclic voltammetry (CV) tests of LaCl{sub 3} in KCl-LiCl molten salt were conducted at low concentration levels in the molten salt at 723 K and at several scan rates. The CV signals were subsequently analyzed through the conventional CV analysis and using a BET-based model through a nonlinear least-squares fitting procedure. It was determined that the parameters of the model were strongly correlated and the support plane procedure was implemented to assign joint confidence intervals for the diffusivity of lanthanum. Accounting for the correlations led to a significant increase in the uncertainty of the reported diffusivity which led to better agreement with the literature. Accounting for the correlations may be important for higher concentration levels.

Distribution of the population for configurations nn, nnn and nnnn of a complex formed by a divalent impurity (M2+) and a vacancy in LiCl and KCl

International Nuclear Information System (INIS)

Cardenas-Garcia, D.; Lopez-Tellez, E.R.

1992-01-01

The distributions of the populations for different configurations of complexes in alkali halides are calculated. It is found that for LiCl the main configuration up to the room temperature is nn. On the other hand, for KCl the nn, nnn and nnnn configurations are equally important at room temperature. Consequently, this should be taken into account when making polarization energy calculations of the complexes. Graphs showing the distribution of the population and the expressions of some thermodynamic relations are included. (Author)

LiCl-KCl-UCl3 Salt production and Transfer for the Uranium Electrorefining

International Nuclear Information System (INIS)

Woo, Moon Sik; Kang, Hee Suk; Lee, Han Soo

2009-01-01

A pyrometallurgical partitioning technology to recover uranium from an uranium-TRU mixture which is the product material of electroreduction system is being developed at KAERI since 1997. In the process, the reactor of an electrorefiner consists of the electrodes and the molten chloride salt which is LiCl-KCl-UCl 3 . The role of uranium chloride salt (UCl 3 ) is to stabilize the initial cell voltage between electrodes in the electrorefining reactor. The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form the CdCl 2 occurring in a Cd layer, followed by a process to produce UCl 3 by the reaction of U in the LiCl-KCl eutectic salt and CdCl 2 . The apparatus for producing UCl 3 consists of a chlorine gas generator, a chlorinator, and a off-gas wet scrubber. The temperature of the reactants are maintained at about 600 .deg. C . After the reaction is completed, the product salt is transferred from the vessel to the electrorefiner by a transfer system

Distillation of LiCl from the LiCl-Li2O molten salt of the electrolytic reduction process

International Nuclear Information System (INIS)

Kim, I.S.; Oh, S.C.; Im, H.S.; Hur, J.M.; Lee, H.S.

2013-01-01

Electrolytic reduction of the uranium oxide in LiCl-Li 2 O molten salt for the treatment of spent nuclear fuel requires the separation of the residual salt from the reduced metal product, which contains about 20 wt% salt. In order to separate the residual salt and reuse it in the electrolytic reduction, a vacuum distillation process was developed. Lab-scale distillation equipment was designed and installed in an argon atmosphere glove box. The equipment consisted of an evaporator in which the reduced metal product was contained and exposed to a high temperature and reduced pressure; a receiver; and a vertically oriented condenser that operated at a temperature below the melting point of lithium chloride. We performed experiments with LiCl-Li 2 O salt to evaluate the evaporation rate of LiCl salt and varied the operating temperature to discern its effect on the behavior of salt evaporation. Complete removal of the LiCl salt from the evaporator was accomplished by reducing the internal pressure to <100 mTorr and heating to 900 deg C. We achieved evaporation efficiency as high as 100 %. (author)

Electroplating of erbium on steel surface in ErCl3 doped LiCl-KCl

International Nuclear Information System (INIS)

Kondo, Masatoshi; Tanaka, Teruya; Muroga, Takeo; Tsujimura, Hiroyuki; Ito, Yasuhiko

2012-01-01

The electroplating of Er metal on the reduced activation ferritic martensitic steel, JLF-1 (Fe-9Cr-2W-0.1C), in a molten salt was studied. The specimen was immersed in the molten ErCl 3 doped LiCl-KCl electrolyte. The electroplating was carried out by a constant potential electrolysis method and a pulsed current electrolysis method. It was found that the Er metal was deposited on the specimen surface due to the electrochemical reaction. (author)

Electrochemical studies and analysis of 1–10 wt% UCl3 concentrations in molten LiCl–KCl eutectic

International Nuclear Information System (INIS)

Hoover, Robert O.; Shaltry, Michael R.; Martin, Sean; Sridharan, Kumar; Phongikaroon, Supathorn

2014-01-01

Three electrochemical methods – cyclic voltammetry (CV), chronopotentiometry (CP), and anodic stripping voltammetry (ASV) – were applied to solutions of up to 10 wt% UCl 3 in the molten LiCl–KCl eutectic salt at 500 °C to determine electrochemical properties and behaviors and to help provide a scientific basis for the development of an in situ electrochemical probe for determining the concentration of uranium in a used nuclear fuel electrorefiner. Diffusion coefficients of UCl 4 and UCl 3 were calculated to be (6.72 ± 0.360) × 10 −6 cm 2 /s and (1.04 ± 0.17) × 10 −5 cm 2 /s, respectively. Apparent standard reduction potentials were determined to be (−0.381 ± 0.013) V and (−1.502 ± 0.076) V vs. 5 mol% Ag/AgCl or (−1.448 ± 0.013) V and (−2.568 ± 0.076) V vs. Cl 2 /Cl − for the U(IV)/U(III) and U(III)/U redox couples, respectively. In comparing this data with supercooled thermodynamic data to determine activity coefficients, the thermodynamic database used was important with resulting activity coefficients ranging from 2.34 × 10 −3 to 1.08 × 10 −2 for UCl 4 and 4.94 × 10 −5 to 4.50 × 10 −4 for UCl 3 . Of anodic stripping voltammetry and cyclic voltammetry anodic or cathodic peaks, the CV cathodic peak height divided by square root of scan rate was shown to be the most reliable method of determining UCl 3 concentration in the molten salt

Electrochemistry of plutonium in molten halides

International Nuclear Information System (INIS)

McCurry, L.E.; Moy, G.M.M.; Bowersox, D.F.

1987-01-01

The electrochemistry of plutonium in molten halides is of technological importance as a method of purification of plutonium. Previous authors have reported that plutonium can be purified by electrorefining impure plutonium in various molten haldies. Work to eluciate the mechanism of the plutonium reduction in molten halides has been limited to a chronopotentiometric study in LiCl-KCl. Potentiometric studies have been carried out to determine the standard reduction potential for the plutonium (III) couple in various molten alkali metal halides. Initial cyclic voltammetric experiments were performed in molten KCL at 1100 K. A silver/silver chloride (10 mole %) in equimolar NaCl-KCl was used as a reference electrode. Working and counter electrodes were tungsten. The cell components and melt were contained in a quartz crucible. Background cyclic voltammograms of the KCl melt at the tungsten electrode showed no evidence of electroactive impurities in the melt. Plutonium was added to the melt as PuCl/sub 3/, which was prepared by chlorination of the oxide. At low concentrations of PuCl/sub 3/ in the melt (0.01-0.03 molar), no reduction wave due to the reduction of Pu(III) was observed in the voltammograms up to the potassium reduction limit of the melt. However on scan reversal after scanning into the potassium reduction limit a new oxidation wave was observed

Interplay between structure and transport properties of molten salt mixtures of ZnCl2-NaCl-KCl: A molecular dynamics study.

Science.gov (United States)

Manga, Venkateswara Rao; Swinteck, Nichlas; Bringuier, Stefan; Lucas, Pierre; Deymier, Pierre; Muralidharan, Krishna

2016-03-07

Molten mixtures of network-forming covalently bonded ZnCl2 and network-modifying ionically bonded NaCl and KCl salts are investigated as high-temperature heat transfer fluids for concentrating solar power plants. Specifically, using molecular dynamics simulations, the interplay between the extent of the network structure, composition, and the transport properties (viscosity, thermal conductivity, and diffusion) of ZnCl2-NaCl-KCl molten salts is characterized. The Stokes-Einstein/Eyring relationship is found to break down in these network-forming liquids at high concentrations of ZnCl2 (>63 mol. %), while the Eyring relationship is seen with increasing KCl concentration. Further, the network modification due to the addition of K ions leads to formation of non-bridging terminal Cl ions, which in turn lead to a positive temperature dependence of thermal conductivity in these melts. This new understanding of transport in these ternary liquids enables the identification of appropriate concentrations of the network formers and network modifiers to design heat transfer fluids with desired transport properties for concentrating solar power plants.

Characterization Ag/AgCl reference electrode by U/U3+ equilibrium potential measurements in LiCl-KCl eutectic melt

International Nuclear Information System (INIS)

Kobayashi, Fumiaki; Kitawaki, Shinichi; Amamoto, Ippei; Igarashi, Miyuki

1999-02-01

The Ag/ AgCl reference electrode is often used in electrochemical measurements of molten chloride system. By measuring the U/U 3+ equilibrium potential in the cell, U(s) | UCl 3 , LiCl-KCl parallel LiCl-KCl, Ag + | Ag (s), the characterization of the Ag/AgCl reference electrode was made. The behavior of two types of reference electrode having either a mullite or a Pyrex-glass membrane bridge was examined. It was confirmed that the two types of reference electrode can be regarded as almost equivalent. The reproducibility of the reading from the electrodes having the identical construction was showing to be within 0.003 V. (author)

Pyro-Electrochemical Reduction of a Mixture of Rare Earth Oxides and NiO in LiCl molten Salt

Energy Technology Data Exchange (ETDEWEB)

Lee, Min Woo; Jeong, Sang Mun [Department of Chemical Engineering, Chungbuk National University, Cheongju (Korea, Republic of)

2017-06-15

An electrochemical reduction of a mixture of NiO and rare earth oxides has been conducted to increase the reduction degree of rare earth oxides. Cyclic voltammetry (CV) measurement was carried out to determine the electrochemical reduction behavior of the mixed oxide in molten LiCl medium. Constant voltage electrolysis was performed with various supplied charges to understand the mechanism of electrochemical reduction of the mixed oxide as a working electrode. After completion of the electrochemical reduction, crystal structure of the reaction intermediates was characterized by using an X-ray diffraction method. The results clearly demonstrate that the rare earth oxide was converted to RE-Ni intermetallics via co-reduction with NiO.

Distribution behavior of uranium, neptunium, rare-earth elements (Y, La, Ce, Nd, Sm, Eu, Gd) and alkaline-earth metals (Sr,Ba) between molten LiCl-KCl eutectic salt and liquid cadmium or bismuth

International Nuclear Information System (INIS)

Kurata, M.; Sakamura, Y.; Hijikata, T.; Kinoshita, K.

1995-01-01

Distribution coefficients of uranium neptunium, eight rare-earth elements (Y, La, Ce, Pr, Nd, Sm, Eu and Gd) and two alkaline-earth metals (Sr and Ba) between molten LiCl-KCl eutectic salt and either liquid cadmium or bismuth were measured at 773 K. Separation factors of trivalent rare-earth elements to uranium or neptunium in the LiCl-KCl/Bi system were by one or two orders of magnitude larger than those in the LiCl-KCl/Cd system. On the contrary, the separation factors of alkaline-earth metals and divalent rare-earth elements to trivalent rare-earth elements were by one or two orders of magnitude smaller in the LiCl-KCl/Bi system. (orig.)

Determination of activity coefficient of lanthanum chloride in molten LiCl-KCl eutectic salt as a function of cesium chloride and lanthanum chloride concentrations using electromotive force measurements

Energy Technology Data Exchange (ETDEWEB)

Bagri, Prashant, E-mail: prashant.bagri@utah.edu; Simpson, Michael F.

2016-12-15

The thermodynamic behavior of lanthanides in molten salt systems is of significant scientific interest for the spent fuel reprocessing of Generation IV reactors. In this study, the apparent standard reduction potential (apparent potential) and activity coefficient of LaCl{sub 3} were determined in a molten salt solution of eutectic LiCl-KCl as a function of concentration of LaCl{sub 3}. The effect of adding up to 1.40 mol % CsCl was also investigated. These properties were determined by measuring the open circuit potential of the La—La(III) redox couple in a high temperature molten salt electrochemical cell. Both the apparent potential and activity coefficient exhibited a strong dependence on concentration. A low concentration (0.69 mol %) of CsCl had no significant effect on the measured properties, while a higher concentration (1.40 mol %) of CsCl caused an increase (become more positive) in the apparent potential and activity coefficient at the higher range of LaCl{sub 3} concentrations.

Method for making a Pellet-type LiCl-KCl-UCl3 SALT

International Nuclear Information System (INIS)

Woo, M. S.; JIN, H. J.; Lee, H. S.; Kim, J. G.

2012-01-01

A pyrometallurgical partitioning technology to recover uranium from a uranium-TRU mixture which is the product material of electroreduction system is being developed at KAERI since 1997. In the process, the reactor of an electrorefiner consists of the electrodes and the molten chloride salt which is LiCl-KCl-UCl 3 . The role of uranium chloride salt (UCl 3 ) is to stabilize the initial cell voltage between electrodes in the electrorefining reactor. The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form CdCl 2 occurring in a Cd layer, followed by a process to produce UCl 3 by the reaction of U in the LiCl-KCl eutectic salt and CdCl 2 The apparatus for producing UCl 3 consists of a chlorine gas generator, a uranium chlorinator, a Cd distiller, the pelletizer, and a off-gas and a dry scrubber. The temperature of the reactants is maintained at about 600 .deg. C. After the reaction is completed in the uranium chlorinator, The salt products is transferred to the Cd distiller to decrease residual Cd concentration in the salts, and then salt is transferred to the mould of a pelletizer by a transfer system to make a pellet type salt

Saturated vapor pressure over molten mixtures of GaCl3 and alkali metal chlorides

International Nuclear Information System (INIS)

Salyulev, A.B.; Smolenskij, V.V.; Moskalenko, N.I.

2004-01-01

Volatilities of GaCl 3 and alkali metal chlorides over diluted (up to 3 mol %) solutions of GaCl 3 in LiCl, NaCl, KCl, RbCl, and CsCl were measured at 1100 K by dynamic and indirect static methods. Chemical composition of saturated vapor over the mixed melts was determined. Partial pressures of the components were calculated. Their values depend essentially on specific alkali metal cation and on concentration of GaCl 3 ; their variation permits altering parameters of GaCl 3 distillation from the salt melt in a wide range [ru

Stabilization/Solidification of radioactive molten salt waste by using xSiO2-yAl2O3-zP2O5 material

International Nuclear Information System (INIS)

Hwan-Seo Park; In-Tae Kim; Yong-Zun Cho; Seong-Won Park; Eung-Ho Kim

2008-01-01

Molten salt waste generated from the electro metallurgical process to recover uranium and transuranic elements is considered as one of problematic wastes to be difficult to immobilize into a durable for final disposal. As an alternative, this study suggested a new method performed at molten state, where dechlorination was achieved with a new inorganic material containing SiO 2 , Al 2 O 3 and P 2 O 5 (SAP). The SAP as a reactive material to molten salt was prepared by a conventional sol-gel process. The prepared SAPs were reacted with each metal chloride, LiCl, CsCl, SrCl 2 and CeCl 3 at 650 deg. C for 6 hours and also were reacted with simulated salt waste consisting of 90 wt% LiCl, 6.8 wt% CsCl and 3.2 wt% SrCl 2 at different waste loading. All the reactions were carried out in oxidative atmosphere and metal chlorides were effectively converted into stable products under a reasonable reaction ratio

Electrochemical studies and analysis of 1–10 wt% UCl{sub 3} concentrations in molten LiCl–KCl eutectic

Energy Technology Data Exchange (ETDEWEB)

Hoover, Robert O., E-mail: roberthoover@vandals.uidaho.edu [Chemical and Materials Engineering Department and Nuclear Engineering Program, University of Idaho, Idaho Falls, Center for Advanced Energy Studies, 995 University Blvd, Idaho Falls, ID 83401 (United States); Shaltry, Michael R., E-mail: mshaltry@uidaho.edu [Chemical and Materials Engineering Department and Nuclear Engineering Program, University of Idaho, Idaho Falls, Center for Advanced Energy Studies, 995 University Blvd, Idaho Falls, ID 83401 (United States); Martin, Sean, E-mail: Sean.martin@xenuclear.com [Department of Engineering Physics, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706 (United States); Sridharan, Kumar, E-mail: kumar@engr.wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706 (United States); Phongikaroon, Supathorn, E-mail: supathor@uidaho.edu [Chemical and Materials Engineering Department and Nuclear Engineering Program, University of Idaho, Idaho Falls, Center for Advanced Energy Studies, 995 University Blvd, Idaho Falls, ID 83401 (United States)

2014-09-15

Three electrochemical methods – cyclic voltammetry (CV), chronopotentiometry (CP), and anodic stripping voltammetry (ASV) – were applied to solutions of up to 10 wt% UCl{sub 3} in the molten LiCl–KCl eutectic salt at 500 °C to determine electrochemical properties and behaviors and to help provide a scientific basis for the development of an in situ electrochemical probe for determining the concentration of uranium in a used nuclear fuel electrorefiner. Diffusion coefficients of UCl{sub 4} and UCl{sub 3} were calculated to be (6.72 ± 0.360) × 10{sup −6} cm{sup 2}/s and (1.04 ± 0.17) × 10{sup −5} cm{sup 2}/s, respectively. Apparent standard reduction potentials were determined to be (−0.381 ± 0.013) V and (−1.502 ± 0.076) V vs. 5 mol% Ag/AgCl or (−1.448 ± 0.013) V and (−2.568 ± 0.076) V vs. Cl{sub 2}/Cl{sup −} for the U(IV)/U(III) and U(III)/U redox couples, respectively. In comparing this data with supercooled thermodynamic data to determine activity coefficients, the thermodynamic database used was important with resulting activity coefficients ranging from 2.34 × 10{sup −3} to 1.08 × 10{sup −2} for UCl{sub 4} and 4.94 × 10{sup −5} to 4.50 × 10{sup −4} for UCl{sub 3}. Of anodic stripping voltammetry and cyclic voltammetry anodic or cathodic peaks, the CV cathodic peak height divided by square root of scan rate was shown to be the most reliable method of determining UCl{sub 3} concentration in the molten salt.

Molten Chloride Salts for Heat Transfer in Nuclear Systems

Science.gov (United States)

Ambrosek, James Wallace

2011-12-01

A forced convection loop was designed and constructed to examine the thermal-hydraulic performance of molten KCl-MgCl2 (68-32 at %) salt for use in nuclear co-generation facilities. As part of this research, methods for prediction of the thermo-physical properties of salt mixtures for selection of the coolant salt were studied. In addition, corrosion studies of 10 different alloys were exposed to the KCl-MgCl2 to determine a suitable construction material for the loop. Using experimental data found in literature for unary and binary salt systems, models were found, or developed to extrapolate the available experimental data to unstudied salt systems. These property models were then used to investigate the thermo-physical properties of the LINO3-NaNO3-KNO 3-Ca(NO3), system used in solar energy applications. Using these models, the density, viscosity, adiabatic compressibility, thermal conductivity, heat capacity, and melting temperatures of higher order systems can be approximated. These models may be applied to other molten salt systems. Coupons of 10 different alloys were exposed to the chloride salt for 100 hours at 850°C was undertaken to help determine with which alloy to construct the loop. Of the alloys exposed, Haynes 230 had the least amount of weight loss per area. Nickel and Hastelloy N performed best based on maximum depth of attack. Inconel 625 and 718 had a nearly uniform depletion of Cr from the surface of the sample. All other alloys tested had depletion of Cr along the grain boundaries. The Nb in Inconel 625 and 718 changed the way the Cr is depleted in these alloys. Grain-boundary engineering (GBE) of Incoloy 800H improved the corrosion resistance (weight loss and maximum depth of attack) by nearly 50% as compared to the as-received Incoloy 800H sample. A high temperature pump, thermal flow meter, and pressure differential device was designed, constructed and tested for use in the loop, The heat transfer of the molten chloride salt was found to

Electroanalytical measurements of binary-analyte mixtures in molten LiCl-KCl eutectic: Uranium(III)- and Magnesium(II)-Chloride

Energy Technology Data Exchange (ETDEWEB)

Rappleye, Devin, E-mail: rappleye1@llnl.gov; Newton, Matthew L.; Zhang, Chao; Simpson, Michael F.

2017-04-01

The electrochemical behavior of MgCl{sub 2} in molten LiCl-KCl eutectic was investigated to evaluate its suitability as a surrogate for PuCl{sub 3} in studies related to the eletrorefining of used nuclear fuel. The reduction of Mg{sup 2+} was found to be electrochemically reversible up to 300 mV s{sup −1} at 773 K. The diffusion coefficient for Mg{sup 2+} was calculated to be 1.74 and 2.17 × 10{sup −5} cm{sup 2} s{sup −1} with and without U{sup 3+} present, respectively, at 773 K using cyclic voltammetry (CV). Upon comparison to literature data, the diffusion coefficient of Mg{sup 2+} differs by only 8.8% (with U{sup 3+} present) from that of Pu{sup 3+} and the difference in peak potentials was only 79 mV. Binary-analyte mixtures of UCl{sub 3} and MgCl{sub 2} in eutectic LiCl-KCl were further investigated using CV, normal pulse voltammetry (NPV), chronoamperometry (CA) and open-circuit potential (OCP) measurements for the purpose of comparing each technique's accuracy in measuring U{sup 3+} and Mg{sup 2+} concentrations. Of all the techniques tested, NPV resulted in the lowest error which was, on average, 11.4% and 9.81% for U{sup 3+} and Mg{sup 2+}, respectively.

Method for making a Pellet-type LiCl-KCl-UCl{sub 3} SALT

Energy Technology Data Exchange (ETDEWEB)

Woo, M. S.; JIN, H. J.; Lee, H. S.; Kim, J. G. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

A pyrometallurgical partitioning technology to recover uranium from a uranium-TRU mixture which is the product material of electroreduction system is being developed at KAERI since 1997. In the process, the reactor of an electrorefiner consists of the electrodes and the molten chloride salt which is LiCl-KCl-UCl{sub 3}. The role of uranium chloride salt (UCl{sub 3}) is to stabilize the initial cell voltage between electrodes in the electrorefining reactor. The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form CdCl{sub 2} occurring in a Cd layer, followed by a process to produce UCl{sub 3} by the reaction of U in the LiCl-KCl eutectic salt and CdCl{sub 2} The apparatus for producing UCl{sub 3} consists of a chlorine gas generator, a uranium chlorinator, a Cd distiller, the pelletizer, and a off-gas and a dry scrubber. The temperature of the reactants is maintained at about 600 .deg. C. After the reaction is completed in the uranium chlorinator, The salt products is transferred to the Cd distiller to decrease residual Cd concentration in the salts, and then salt is transferred to the mould of a pelletizer by a transfer system to make a pellet type salt

Electrochemical behavior of zirconium in the LiCl-KCl molten salt at Mo electrode

Energy Technology Data Exchange (ETDEWEB)

Chen Zeng; Li Yongjun [Key Laboratory of Photovoltaic Materials of Henan Province and School of Physics and Electronics, Henan, University, Kaifeng 475001 (China); Li Shengjun, E-mail: lishengjun@hrbeu.edu.cn [Key Laboratory of Photovoltaic Materials of Henan Province and School of Physics and Electronics, Henan, University, Kaifeng 475001 (China)

2011-05-19

Highlights: > The electrochemical reduction of Zr(II)/Zr and Zr(IV)/Zr(II) were both proved to be diffusion-controlled process. > In the 773 K-973 K range, the diffusion coefficients of Zr(II) and Zr(IV) were determined: D{sub Zr(II)} = 0.15567exp{l_brace}-69.65 x 10{sup 3}RT(K){r_brace} cm{sup 2}/s, D{sub Zr(IV)} = 1.09 x 10{sup -4}exp{l_brace}-44.39 x 10{sup 3}RT(K){r_brace} cm{sup 2}/s. > The activation energy values for the diffusion process were 69.65 kJ/mol and 44.39 kJ/mol, respectively. > This investigation will be useful for the further cognition of the molten salt electrolysis of zirconium. - Abstract: The electroreduction process of Zr(IV) was studied at molybdenum electrode in LiCl-KCl-K{sub 2}ZrF{sub 6} molten salt. The transient electrochemical techniques, such as cyclic voltammetry and chronopotenimetry were used. The experimental results showed that the electrochemical reduction of Zr(II)/Zr and Zr(IV)/Zr(II) were both diffusion-controlled process. In the 773-973 K range, the diffusion coefficients of Zr(ii) and Zr(IV) were determined: D{sub Zr(II)} = 0.15567exp{l_brace}-69.65 x 10{sup 3}RT(K){r_brace} cm{sup 2}/s, D{sub Zr(IV)} = 1.09 x 10{sup -4} exp{l_brace}-44.39 x 10{sup 3}RT(K){r_brace} cm{sup 2}/s. The activation energy values for the diffusion process were 69.65 kJ/mol and 44.39 kJ/mol, respectively.

Laser-Induced Breakdown Spectroscopy (LIBS) in a Novel Molten Salt Aerosol System.

Science.gov (United States)

Williams, Ammon N; Phongikaroon, Supathorn

2017-04-01

In the pyrochemical separation of used nuclear fuel (UNF), fission product, rare earth, and actinide chlorides accumulate in the molten salt electrolyte over time. Measuring this salt composition in near real-time is advantageous for operational efficiency, material accountability, and nuclear safeguards. Laser-induced breakdown spectroscopy (LIBS) has been proposed and demonstrated as a potential analytical approach for molten LiCl-KCl salts. However, all the studies conducted to date have used a static surface approach which can lead to issues with splashing, low repeatability, and poor sample homogeneity. In this initial study, a novel molten salt aerosol approach has been developed and explored to measure the composition of the salt via LIBS. The functionality of the system has been demonstrated as well as a basic optimization of the laser energy and nebulizer gas pressure used. Initial results have shown that this molten salt aerosol-LIBS system has a great potential as an analytical technique for measuring the molten salt electrolyte used in this UNF reprocessing technology.

The electrolytic deposition of carbon from molten Li2CO3

International Nuclear Information System (INIS)

Dimitrov, A.T.

2003-01-01

Electrodeposition of carbon on an nickel electrode in molten salt has been investigated with the aid of scanning electron microscopy (SEM) and cyclic voltammetry, using molten LiCl, as a base electrolyte with adding of 1 and 5 % of Li 2 CO 3 . Commercial nickel wire was used as a cathode and graphite crucible as the anode electrode. A cyclic voltammograms for an nickel electrode indicates that the deposition or discharge of carbon at the cathode occurs at potential range of - 0.8 to -1.7 V. Further, SEM observations showed that morphology of the carbon at the cathode is in the form of a fairly hard black deposit. It was found that the quality of the deposit depends by the cathode surface, applied overpotential, content of lithium carbonate and the thickness of the carbon film. (Original)

A study on the corrosion test of equipment material handling hot molten salt

International Nuclear Information System (INIS)

Ro, Seung Gy; Jeong, M.S.; Hong, S.S.; Cho, S.H.; Shin, Y.J.; Park, H.S.; Zhang, J.S.

1999-02-01

On this technical report, corrosion behavior of austenitic stainless steels of SUS 316L and SUS 304L in molten salt of LiCl-Li 2 O has been investigated in the temperature range of 650 - 850 dg C. Corrosion products of SUS 316L in molten salt consisted of two layers, an outer layer of LiCrO 2 and inner layer of Cr 2 O 3 .The corrosion layer was uniform in molten salt of LiCl, but the intergranular corrosion occurred in addition to the uniform corrosion in mixed molten salt of LiCl-Li 2 O. The corrosion rate increased slowly with the increase of temperature up to 750 dg C, but above 750 dg C rapid increase in corrosion rate observed. SUS 316L stainless steel showed slower corrosion rate and higher activation energy for corrosion than SUS 304L, exhibiting higher corrosion resistance in the molten salt. In heat-resistant alloy, dense protective oxide scale of LiCrO 2 was formed in molten salt of LiCl. Whereas in mixed molten salt of LiCl-Li 2 O, porous non-protective scale of Li(Cr, Ni, Fe)O 2 was formed. (Author). 44 refs., 4 tabs., 16 figs

Development of viscometers for molten salts

International Nuclear Information System (INIS)

Hayashi, Hirokazu; Kato, Yoshio; Ogawa, Toru; Sato, Yuzuru.

1997-06-01

Viscometers specially designed for molten salts were made. One is a oscillating cup type and the other is a capillary type. In the case of the oscillating cup viscometer, the viscosity is determined absolutely through the period and the logarithmic decrement of oscillation with other physical parameters. The period and the logarithmic decrement are calculated from the time intervals between two photo-detectors' intercepts of the reflected laser beam. The capillary viscometer used is made of quartz and the sample is sealed under vacuum, which is placed in a transparent furnace. Efflux time is measured by direct visual observation. Cell constants are determined with distilled water as a calibrating liquid. Viscosities of molten KCl are measured with each viscometer. The differences between measured and standard values of molten KCl at several temperatures are within 5% for the oscillating cup viscometer and within 3% for the capillary viscometer. (author)

Stabilization/Solidification of Radioactive LiCl-KCl Waste Salt by Using SiO2-Al2O3-P2O5(SAP) Inorganic Composite: Part 1. Dechlorination Behavior of LiCl-KCl and Characteristics of Consolidation

International Nuclear Information System (INIS)

Cho, In Hak; Park, Hwan Seo; Ahn, Soo Na; Kim, In Tae; Cho, Yong Zun

2012-01-01

The metal chloride wastes from a pyrochemical process to recover uranium and transuranic elements has been considered as a problematic waste difficult to apply to a conventional solidification method due to the high volatility and low compatibility with silicate glass. In this study, a dechlorination approach to treat LiCl-KCl waste for final disposal was adapted. In this study, a SiO 2 -Al 2 O 3 -P 2 O 5 (SAP) inorganic composite as a dechlorination agent was prepared by a conventional sol-gel process. By using a series of SAPs, the dechlorination behavior and consolidation of reaction products were investigated. Different from LiCl waste, the dechlorination reaction occurred mainly at two temperature ranges. The thermogravimetric test indicated that the first reaction range was about 400 degree C for LiCl and the second was about 700 degree C for KCl. The SAP 1071 (Si/Al/P=1/0.75/1 in molar) was found to be the most favorable SAP as a dechlorination agent under given conditions. The consolidation test revealed that the bulk shape and the densification of consolidated forms depended on the SAP/Salt ratios. The leaching test by PCT-A method was performed to evaluate the durability of consolidated forms. This study provided the basic information on the dechlorination approach. Based on the experimental results, the dechlorination method using a SiO 2 -Al 2 O 3 -P 2 O 5 (SAP) could be considered as one of alternatives for the immobilization of waste salt.

Stabilization/Solidification of radioactive molten salt waste by using xSiO{sub 2}-yAl{sub 2}O{sub 3}-zP{sub 2}O{sub 5} material

Energy Technology Data Exchange (ETDEWEB)

Hwan-Seo Park; In-Tae Kim; Yong-Zun Cho; Seong-Won Park; Eung-Ho Kim [Korea Atomic Energy Research Institute: 150 Deokjin-dong, Yuseong, Daejeon, 305-353 (Korea, Republic of)

2008-07-01

Molten salt waste generated from the electro metallurgical process to recover uranium and transuranic elements is considered as one of problematic wastes to be difficult to immobilize into a durable for final disposal. As an alternative, this study suggested a new method performed at molten state, where dechlorination was achieved with a new inorganic material containing SiO{sub 2}, Al{sub 2}O{sub 3} and P{sub 2}O{sub 5} (SAP). The SAP as a reactive material to molten salt was prepared by a conventional sol-gel process. The prepared SAPs were reacted with each metal chloride, LiCl, CsCl, SrCl{sub 2} and CeCl{sub 3} at 650 deg. C for 6 hours and also were reacted with simulated salt waste consisting of 90 wt% LiCl, 6.8 wt% CsCl and 3.2 wt% SrCl{sub 2} at different waste loading. All the reactions were carried out in oxidative atmosphere and metal chlorides were effectively converted into stable products under a reasonable reaction ratio.

A study on the reduction of uranium oxide to uranium metal in LiCl molten salt

International Nuclear Information System (INIS)

Seo, J. S.; Hur, J. M.; Lee, W. K.; Hong, S. S.; Kang, D. S.; Park, S. W.

2002-01-01

Research for the analysis on a metallization process of uranium oxide in LiCl-Li molten salt was carried out. Effect of a concentration of Li 2 O on the metallization process was also studied. The new concept, electrochemical reduction of uranium oxide in LiCl-Li 2 O molten salt was proposed. The concept is based on the integrated process of metallization of UO 2 with simultaneous electrochemical reduction of Li 2 O which is recycled in a closed system. In a LiCl-Li molten salt system, U 3 O 8 whose conversion ratio to U turns out to be 97.1%, showed a better metallization characteristic than UO 2 . It is verified that electrochemically reduced Li is well deposited on the UO 2 powder cathode through a porous magnesia filter in LiCl-Li 2 O molten salt. In that process Li 2 O was from by the reduction process of UO 2 to U. This electrochemical reduction process showed good results to covert UO 2 to U

A study of integrated cathode assembly for electrolytic reduction of uranium oxide in LiCl-Li2O molten salt

International Nuclear Information System (INIS)

Park, Sung Bin; Seo, Jung Seok; Kang, Dae Seung; Kwon, Sun Kil; Park, Seong Won

2004-01-01

Interest of electrolytic reduction of uranium oxide is increasing in treatment of spent metal fuels. Argonne National Laboratory (ANL) has reported the experimental results of electrochemical reduction of uranium oxide fuel in bench-scale apparatus with cyclic voltammetry, and has designed high-capacity reduction (HCR) cells and conducted three kg-scale UO 2 reduction runs. From the cyclic voltammograms, the mechanism of electrolytic reduction of metal oxides is analyzed. The uranium oxide in LiCl-Li 2 O is converted to uranium metal according to the two mechanism; direct and indirect electrolytic reduction. In this study, cyclic voltammograms for LiCl-3wt% Li 2 O system and U 3 O 8 -LiCl-3wt% Li 2 O system using the 325-mesh stainless steel screen in cathode assembly have been obtained. Direct electrolytic reduction of uranium oxide in LiCl-3wt% Li 2 O molten salt has been conducted

Study for electrochemical behavior of uranium oxide in a molten LiCl-Li2O system

International Nuclear Information System (INIS)

Park, Sung Bin; Park, Byung Heung; Seo, Chung Seok; Jung, Ki Jung; Park, Seong Won

2005-01-01

Interest in the electrolytic reduction of uranium oxide is increasing in the treatment of spent fuel oxides. With complicated and expensive procedures many reactive metals can be prepared in a pure metal form, the electrochemical reduction of a metal oxide has been recently proposed in metallurgy. The electrochemical reduction process is simple and rapid when compared to the conventional processes. The process can reduce the production costs and be applicable to a wide range of metal oxides. Chen et al. proposed the direct electrochemical reduction of titanium dioxide to titanium in a molten calcium chloride. Argonne National Laboratory (ANL) has reported the experimental results of an electrochemical reduction of the uranium oxide fuel in a bench-scale apparatus with a cyclic voltammetry, and has designed high-capacity reduction (HCR) cells and conducted three kg-scale UO 2 reduction runs. Gourishankar et al. classified the mechanisms of the electrolytic reduction of the metal oxides in a LiCl-Li 2 O molten salt system into two types; the simultaneous reduction and the direct electrochemical reduction. The uranium oxide in LiCl-Li 2 O molten salt was converted to uranium metal according to two mechanisms. Korea Atomic Energy Research Institute (KAERI) has developed the Advanced Spent Fuel Conditioning Process (ACP) to be an innovative technology in handling the PWR spent fuel. As part of ACP, the electrolytic reduction process (ER process) is the electrochemical reduction process of uranium oxide to uranium metal in molten salt. The ER process has advantages in a technical stability, an economic potential and a good proliferation resistance. KAERI has reported on the good experimental results of an electrochemical reduction of the uranium oxide in a 20 kg HM/batch lab-scale. In this work, cyclic voltammograms for a LiCl-3 wt% Li 2 O system and an U 3 O 8 -LiCl-3 wt% Li 2 O system with the integrated cathode assembly have been obtained. From the cyclic

Electrochemical studies on plutonium in molten salts

International Nuclear Information System (INIS)

Bourges, G.; Lambertin, D.; Rochefort, S.; Delpech, S.; Picard, G.

2007-01-01

Electrochemical studies on plutonium have been supporting the development of pyrochemical processes involving plutonium at CEA. The electrochemical properties of plutonium have been studied in molten salts - ternary eutectic mixture NaCl-KCl-BaCl 2 , equimolar mixture NaCl-KCl and pure CaCl 2 - and in liquid gallium at 1073 K. The formal, or apparent, standard potential of Pu(III)/Pu redox couple in eutectic mixture of NaCl-KCl-BaCl 2 at 1073 K determined by potentiometry is equal to -2.56 V (versus Cl 2 , 1 atm/Cl - reference electrode). In NaCl-KCl eutectic mixture and in pure CaCl 2 the formal standard potentials deduced from cyclic voltammetry are respectively -2.54 V and -2.51 V. These potentials led to the calculation of the activity coefficients of Pu(III) in the molten salts. Chronoamperometry on plutonium in liquid gallium using molten chlorides - CaCl 2 and equimolar NaCl/KCl - led to the determination of the activity coefficient of Pu in liquid Ga, log γ = -7.3. This new data is a key parameter to assess the thermodynamic feasibility of a process using gallium as solvent metal. By comparing gallium with other solvent metals - cadmium, bismuth, aluminum - gallium appears to be, with aluminum, more favorable for the selectivity of the separation at 1073 K of plutonium from cerium. In fact, compared with a solid tungsten electrode, none of these solvent liquid metals is a real asset for the selectivity of the separation. The role of a solvent liquid metal is mainly to trap the elements

Calculation of NaCl, KCl and LiCl Salts Activity Coefficients in Polyethylene Glycol (PEG4000)-Water System Using Modified PHSC Equation of State, Extended Debye-Hückel Model and Pitzer Model

Science.gov (United States)

Marjani, Azam

2016-07-01

For biomolecules and cell particles purification and separation in biological engineering, besides the chromatography as mostly applied process, aqueous two-phase systems (ATPS) are of the most favorable separation processes that are worth to be investigated in thermodynamic theoretically. In recent years, thermodynamic calculation of ATPS properties has attracted much attention due to their great applications in chemical industries such as separation processes. These phase calculations of ATPS have inherent complexity due to the presence of ions and polymers in aqueous solution. In this work, for target ternary systems of polyethylene glycol (PEG4000)-salt-water, thermodynamic investigation for constituent systems with three salts (NaCl, KCl and LiCl) has been carried out as PEG is the most favorable polymer in ATPS. The modified perturbed hard sphere chain (PHSC) equation of state (EOS), extended Debye-Hückel and Pitzer models were employed for calculation of activity coefficients for the considered systems. Four additional statistical parameters were considered to ensure the consistency of correlations and introduced as objective functions in the particle swarm optimization algorithm. The results showed desirable agreement to the available experimental data, and the order of recommendation of studied models is PHSC EOS > extended Debye-Hückel > Pitzer. The concluding remark is that the all the employed models are reliable in such calculations and can be used for thermodynamic correlation/predictions; however, by using an ion-based parameter calculation method, the PHSC EOS reveals both reliability and universality of applications.

Molten salt engineering for thorium cycle. Electrochemical studies as examples

International Nuclear Information System (INIS)

Ito, Yasuhiko

1998-01-01

A Th-U nuclear energy system utilizing accelerator driven subcritical molten salt breeder reactor has several advantages compared to conventional U-Pu nuclear system. In order to obtain fundamental data on molten salt engineering of Th-U system, electrochemical study was conducted. As the most primitive simulated study of beam irradiation of molten salt, discharge electrolysis was investigated in molten LiCl-KCl-AgCl system. Stationary discharge was generated under atmospheric argon gas and fine Ag particles were obtained. Hydride ion (H - ) behavior in molten salts was also studied to predict the behavior of tritide ion (T - ) in molten salt fuel. Finally, hydrogen behavior in metals at high temperature was investigated by electrochemical method, which is considered to be important to confine and control tritium. (author)

Separation of actinides from irradiated An–Zr based fuel by electrorefining on solid aluminium cathodes in molten LiCl–KCl

Energy Technology Data Exchange (ETDEWEB)

Souček, P., E-mail: Pavel.Soucek@ec.europa.eu [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Murakami, T. [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Claux, B.; Meier, R.; Malmbeck, R. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Tsukada, T. [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Glatz, J.-P. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany)

2015-04-15

Highlights: • Electrorefining process in molten LiCl-KCl using solid Al electrodes was demonstrated. • High separation factors of actinides over lanthanides were achieved. • Efficient recovery of actinides from irradiated nuclear fuel was achieved. • Uniform, dense and well adhered deposits were obtained and characterised. • Kinetic parameters of actinide–aluminium alloy formation were evaluated. - Abstract: An electrorefining process for metallic spent nuclear fuel treatment is being investigated in ITU. Solid aluminium cathodes are used for homogeneous recovery of all actinides within the process carried out in molten LiCl–KCl eutectic salt at a temperature of 500 °C. As the selectivity, efficiency and performance of solid Al has been already shown using un-irradiated An–Zr alloy based test fuels, the present work was focused on laboratory-scale demonstration of the process using irradiated METAPHIX-1 fuel composed of U{sub 67}–Pu{sub 19}–Zr{sub 10}–MA{sub 2}–RE{sub 2} (wt.%, MA = Np, Am, Cm, RE = Nd, Ce, Gd, Y). Different electrorefining techniques, conditions and cathode geometries were used during the experiment yielding evaluation of separation factors, kinetic parameters of actinide–aluminium alloy formation, process efficiency and macro-structure characterisation of the deposits. The results confirmed an excellent separation and very high efficiency of the electrorefining process using solid Al cathodes.

Reduction behavior of UO22+ in molten LiCl–RbCl and LiCl–KCl eutectics by using tungsten

International Nuclear Information System (INIS)

Nagai, Takayuki; Uehara, Akihiro; Fujii, Toshiyuki; Yamana, Hajimu

2013-01-01

The reduction of uranium from UO 2 2+ to UO 2 + or U 4+ in molten LiCl–RbCl and LiCl–KCl eutectics was examined by using tungsten and chlorine gas. Spectrophotometric technique was adopted to determine the concentration of uranium species. When tungsten was immersed into the LiCl–RbCl eutectic melt at 400 °C without supplying chlorine gas, 36% of the total weight of the hexavalent of UO 2 2+ was reduced to the pentavalent of UO 2 + . Under purging chlorine gas into the melt, 96% of UO 2 2+ was reduced to the tetravalent of U 4+ . Tungsten oxy-chloride of WOCl 4 was produced via the reductions of UO 2 2+ , which was volatized from the melt and adsorbed on the upper part of experimental cell. On the other hand, 84% of UO 2 2+ in the LiCl–KCl eutectic melt at 500 °C was reduced to U 4+ by using tungsten and chlorine gas

Reduction behavior of UO22+ in molten LiCl-RbCl and LiCl-KCl eutectics by using tungsten

Science.gov (United States)

Nagai, Takayuki; Uehara, Akihiro; Fujii, Toshiyuki; Yamana, Hajimu

2013-08-01

The reduction of uranium from UO22+ to UO2+ or U4+ in molten LiCl-RbCl and LiCl-KCl eutectics was examined by using tungsten and chlorine gas. Spectrophotometric technique was adopted to determine the concentration of uranium species. When tungsten was immersed into the LiCl-RbCl eutectic melt at 400 °C without supplying chlorine gas, 36% of the total weight of the hexavalent of UO22+ was reduced to the pentavalent of UO2+. Under purging chlorine gas into the melt, 96% of UO22+ was reduced to the tetravalent of U4+. Tungsten oxy-chloride of WOCl4 was produced via the reductions of UO22+, which was volatized from the melt and adsorbed on the upper part of experimental cell. On the other hand, 84% of UO22+ in the LiCl-KCl eutectic melt at 500 °C was reduced to U4+ by using tungsten and chlorine gas.

Effect of oxide ion concentration on the electrochemical oxidation of carbon in molten LiCl

International Nuclear Information System (INIS)

Yun, J. W.; Choi, I. K.; Park, Y. S.; Kim, W. H.

2001-01-01

The continuous measurement of lithium oxide concentration was required in DOR (Direct Oxide Reduction) process, which converts spent nuclear fuel to metal form, for the reactivity monitor and effective control of the process. The concentration of lithium oxide was measured by the electrochemical method, which was based on the phenomenon that carbon atoms of glassy carbon electrode electrochemically react with oxygen ions of lithium oxide in molten LiCl medium. From the results of electrode polarization experiments, the trend of oxidation rate of carbon atoms was classified into two different regions, which were proportional and non-proportional ones, dependent on the amount of lithium oxide. Below about 2.5 wt % Li 2 O, as the carbon atom ionization rate was fast enough for reacting with diffusing lithium oxide to the surface of carbon electrode. In this concentration range, the oxidation rate of carbon atoms was controlled by the diffusion of lithium oxide, and the concentration of lithium oxide could be measured by electrochemical method. But, above 2.5 wt % Li 2 O, the oxidation rate of carbon atoms was controlled by the applied electrochemical potential, because the carbon atom ionization rate was suppressed by the huge amounts of diffusing Li 2 O. Above this concentration, the electrochemical method was not applicable to determine the concentration of lithium oxide

Zirconium behaviour during electrorefining of actinide-zirconium alloy in molten LiCl-KCl on aluminium cathodes

Energy Technology Data Exchange (ETDEWEB)

Meier, R. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, Karlsruhe 76125 (Germany); Heidelberg University, Institute of Physical Chemistry, Im Neuenheimer Feld 253, Heidelberg 69120 (Germany); Souček, P., E-mail: Pavel.Soucek@ec.europa.eu [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, Karlsruhe 76125 (Germany); Malmbeck, R.; Krachler, M.; Rodrigues, A.; Claux, B.; Glatz, J.-P. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, Karlsruhe 76125 (Germany); Fanghänel, Th. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, Karlsruhe 76125 (Germany); Heidelberg University, Institute of Physical Chemistry, Im Neuenheimer Feld 253, Heidelberg 69120 (Germany)

2016-04-15

A pyrochemical electrorefining process for the recovery of actinides from metallic nuclear fuel based on actinide-zirconium alloys (An–Zr) in a molten salt is being investigated. In this process actinides are group-selectively recovered on solid aluminium cathodes as An–Al alloys using a LiCl–KCl eutectic melt at a temperature of 450 °C. In the present study the electrochemical behaviour of zirconium during electrorefining was investigated. The maximum amount of actinides that can be oxidised without anodic co-dissolution of zirconium was determined at a selected constant cathodic current density. The experiment consisted of three steps to assess the different stages of the electrorefining process, each of which employing a fresh aluminium cathode. The results indicate that almost a complete dissolution of the actinides without co-dissolution of zirconium is possible under the applied experimental conditions. - Highlights: • Recovery of actinides was shown by electrorefining of U/Pu–Zr alloys in LiCl–KCl. • Constant current density of 20 mA/cm{sup 2} is applied. • Most of the actinides were dissolved avoiding zirconium co-dissolution. • Deterioration of the deposit quality by a small amount of co-deposited Zr is not observed.

Recovery of uranium from uranium and lanthanides in LiCl-KCl molten salt by electrowinning including Cd-Li anode

International Nuclear Information System (INIS)

Woo, Moon Shik; Kim, Eung Ho

2005-01-01

A trans-uranium (TRU) fuel should be manufactured and loaded in transmutation systems in order to transmute the long-lived TRU nuclides into short-lived ones. However, since all of the TRU nuclides are not completely transmuted in one cycle lifetime in transmutation systems, the spent TRU fuel has to be treated to recover the long-lived radionuclides or fuel matrix materials. One concept to manufacture TRU fuel for transmutation is to recover uranium from TRU and molten salt. If this type of fuel is adopted for transmutation, uranium could also be an objective material to be recovered and recycled. Since electrowinning is a promising technology to be employed for the recovery of uranium from fuel materials, some experimental work of electrowinning using anode of Cd-Li alloy was carried out in this study. The basic salt chosen was a mixture of LiCl-KCl which has an eutectic point at 357 .deg. C

Stabilization/Solidification of Radioactive LiCl-KCl Waste Salt by Using SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}(SAP) Inorganic Composite: Part 1. Dechlorination Behavior of LiCl-KCl and Characteristics of Consolidation

Energy Technology Data Exchange (ETDEWEB)

Cho, In Hak; Park, Hwan Seo; Ahn, Soo Na; Kim, In Tae; Cho, Yong Zun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-03-15

The metal chloride wastes from a pyrochemical process to recover uranium and transuranic elements has been considered as a problematic waste difficult to apply to a conventional solidification method due to the high volatility and low compatibility with silicate glass. In this study, a dechlorination approach to treat LiCl-KCl waste for final disposal was adapted. In this study, a SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5} (SAP) inorganic composite as a dechlorination agent was prepared by a conventional sol-gel process. By using a series of SAPs, the dechlorination behavior and consolidation of reaction products were investigated. Different from LiCl waste, the dechlorination reaction occurred mainly at two temperature ranges. The thermogravimetric test indicated that the first reaction range was about 400 degree C for LiCl and the second was about 700 degree C for KCl. The SAP 1071 (Si/Al/P=1/0.75/1 in molar) was found to be the most favorable SAP as a dechlorination agent under given conditions. The consolidation test revealed that the bulk shape and the densification of consolidated forms depended on the SAP/Salt ratios. The leaching test by PCT-A method was performed to evaluate the durability of consolidated forms. This study provided the basic information on the dechlorination approach. Based on the experimental results, the dechlorination method using a SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}(SAP) could be considered as one of alternatives for the immobilization of waste salt.

Absorption behavior of iodine from molten salt mixture to zeolite

International Nuclear Information System (INIS)

Sugihara, Kei; Terai, Takayuki; Suzuki, Akihiro; Uozumi, Koichi; Tsukada, Takeshi; Koyama, Tadafumi

2011-01-01

Behavior of zeolite to absorb anion fission product (FP) elements in molten LiCl-KCl eutectic salt was studied using iodine. At first, zeolite-A was selected as the suitable type of zeolite among zeolite-A (powder), zeolite-X (powder and granule), and zeolite-Y (powder) through experiments to heat the zeolite together with LiCl-KCl-KI salt, respectively. As the next step, similar experiments to immerse zeolite-A in molten LiCl-KCl-KI salt containing various concentrations of iodine were performed. The affinity of iodine to zeolite was evaluated using the separation factor (SF) value, which is defined as [I/(I+Cl) mol ratio in zeolite after immersion]/[I/(I+Cl) mol ratio in salt after immersion]. Since the SF values ranged between 4.3 and 9.1, stronger affinity of iodine than chlorine to zeolite-A was revealed. Finally, influence of co-existing cation FPs was studied by similar absorption experiments in LiCl-KCl-KI salt containing CsCl, SrCl 2 , or NdCl 3 . The SF values were less than those obtained in the LiCl-KCl-KI salt and this can be ascribed to the sharing of inner space of zeolite cage among absorbed cations and anions. (author)

Saturated vapor pressure over molten mixtures of GaCl{sub 3} and alkali metal chlorides; Davlenie nasyshchennykh parov rasplavlennykh smesej CaCl{sub 3} s khloridami shchelochnykh metallov

Energy Technology Data Exchange (ETDEWEB)

Salyulev, A B; Smolenskij, V V; Moskalenko, N I [UrO RAN, Inst. Vysokotemperaturnoj Ehlektrokhimii, Elaterinburg (Russian Federation)

2004-07-01

Volatilities of GaCl{sub 3} and alkali metal chlorides over diluted (up to 3 mol %) solutions of GaCl{sub 3} in LiCl, NaCl, KCl, RbCl, and CsCl were measured at 1100 K by dynamic and indirect static methods. Chemical composition of saturated vapor over the mixed melts was determined. Partial pressures of the components were calculated. Their values depend essentially on specific alkali metal cation and on concentration of GaCl{sub 3}; their variation permits altering parameters of GaCl{sub 3} distillation from the salt melt in a wide range.

Thermodynamics of La and U and the separation factor of U/La in fused Me(Ga-40 wt.% In)/3LiCl-2KCl system

Science.gov (United States)

Smolenski, Valeri; Novoselova, Alena; Volkovich, Vladimir A.

2017-11-01

Separation of lanthanides and actinides can be achieved in a unique "molten chloride - liquid metal" system. Electrode potentials were recorded vs. Cl-/Cl2 reference electrode and the temperature dependencies of the apparent standard potentials of La-(Ga-In) and U-(Ga-In) alloys were determined. Thermodynamic properties and separation factor of lanthanum and uranium were calculated. The obtained data show the perspective for using this system in future innovation method for recovery of nuclear waste.

Obtainment of lithium metal by electrolysis of molten salts

International Nuclear Information System (INIS)

Silva Costa, M.A.Z. da.

1988-04-01

The obtainment metallic lithium through KCL + LiCl, using a stainless steel cathode and a graphite anode is studied. The applications of lithium on nuclear energy, aerospatial program, metalurgy and as refining and degassing agent are also presented. The purification of lithium is still mentioned. (C.G.C.) [pt

A analysis of molten salt separation system for nuclear wastes transmutation

Energy Technology Data Exchange (ETDEWEB)

Hwang, In Soon; Park, Byung Gi [Seoul National University, Seoul (Korea, Republic of); Kim, Kwang Bum; Kwon, Ou Sung [Yonsei University, Seoul (Korea, Republic of)

1997-07-01

Typical molten salt separation is ANL-IFR pyroprocessing and ORNL-MSRE pyroprocessing. IFR pyroprocessing is based on Chloride chemistry and electrorefining. MSRE pyroprocessing is base on fluoride chemistry and reductive extraction. Major technologies of molten salt separation are electrorefining, electrowining, reductive extraction, and oxide reduction. Common characteristics of this technologies is to utilize reduction-oxidation phenomena in molten salt. Electrorefining process is modeled on the basis of diffusion layer theory and Butler-Volmor relation. This model is numerically solved by LSODA package. To acquire the technology of electrorefining process, 3-electrode electrochemical cell is developed where electrolyte is 500 degree C LiCl-KCl eutectic molten salt, working electrodes are Ni and Au, and reference electrode is Ag/AgCl. We have investigated the stable potential range using cyclic voltammogram of Ni electrode. We have measured steady state polarization curve of Ni electrode. Then corrosion potential of Ni electrode is -0.38V{sub Ag/AgCl} and corrosion current is 1.23 x 10{sup -4} A/cm{sup 2}. 12 refs., 6 tabs., 24 figs. (author)

Rare Earth Electrochemical Property Measurements and Phase Diagram Development in a Complex Molten Salt Mixture for Molten Salt Recycle

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jinsuo; Guo, Shaoqiang

2018-03-30

novel process using a galvanic couple between a cathode basket made of stainless steel and a Gd rod is investigated in LiCl-KCl-UCl3-MgCl2. The process shows rapid reduction of UCl3 to U and MgCl2 to Mg without any co-reduction of LaCl3, NdCl3, or CeCl3 because of the higher standard potential of Gd3+/Gd. Electrolysis of the molten salt results in a perturbation of the composition, which in turn can affect the equilibrium phase behavior. Studies on phase behavior in more complex salt mixtures as will be encountered in real electrorefiner salt drawdown are very limited. In present research, the solidus and liquidus temperatures for four quaternary LiCl-KCl-CsCl-RECl3 (RE = La, Nd, Ce, and Gd) salt systems are analyzed by differential scanning calorimetry (DSC) measurement. The presence of CsCl causes a slight depression in the liquidus temperature for all of the four rare earth chloride mixtures when compared to the corresponding ternary system liquidus temperatures in the absence of any CsCl. Thermodynamic assessment for the LiCl-KCl-LnCl3 ternary system(here Gd as a reprehensive of Ln) has been carried out by CALPHAD method using two-sublattice model. From the optimized phase diagram, the solubility of GdCl3 in LiCl-KCl eutectic is obtained. This model can also be applied to other salt system to evaluate the thermodynamic properties of other REs in pyroprocessing salt systems with more components. In the end, an electrolysis model is developed to predict the electrolysis process for RE drawdown from LiCl-KCl salt. The model considers both the diffusion in electrolyte and Faraday process on the electrode surface and a surface layer is introduced to account for the fact that diffusion current is not necessarily equal to the current due to the Butler-Volmer equation. Using the fundamental data obtained from this study, the proposed model is validated by chronoamperometry and chronopotentiometry experimental data.

Chemical Reduction of SIM MOX in Molten Lithium Chloride Using Lithium Metal Reductant

Science.gov (United States)

Kato, Tetsuya; Usami, Tsuyoshi; Kurata, Masaki; Inoue, Tadashi; Sims, Howard E.; Jenkins, Jan A.

2007-09-01

A simulated spent oxide fuel in a sintered pellet form, which contained the twelve elements U, Pu, Am, Np, Cm, Ce, Nd, Sm, Ba, Zr,Mo, and Pd, was reduced with Li metal in a molten LiCl bath at 923 K. More than 90% of U and Pu were reduced to metal to form a porous alloy without significant change in the Pu/U ratio. Small fractions of Pu were also combined with Pd to form stable alloys. In the gap of the porous U-Pu alloy, the aggregation of the rare-earth (RE) oxide was observed. Some amount of the RE elements and the actinoides leached from the pellet. The leaching ratio of Am to the initially loaded amount was only several percent, which was far from about 80% obtained in the previous ones on simple MOX including U, Pu, and Am. The difference suggests that a large part of Am existed in the RE oxide rather than in the U-Pu alloy. The detection of the RE elements and actinoides in the molten LiCl bath seemed to indicate that they dissolved into the molten LiCl bath containing the oxide ion, which is the by-product of the reduction, as solubility of RE elements was measured in the molten LiCl-Li2O previously.

Residual Salt Separation from the Metal Products Reduced in a LiCl-Li2O Molten Salt

International Nuclear Information System (INIS)

Hur, Jin Mok; Hong, Sun Seok; Kang, Dae Seung; Jeong, Meong Soo; Seo, Chung Seok

2006-02-01

The electrochemical reduction of spent nuclear fuel in a LiCl-Li 2 O molten salt for the conditioning of spent nuclear fuel requires the separation of the residual salts from a reduced metal product after the reduction process. Considering the behavior of spent nuclear fuel during the electrochemical reduction process, a surrogate material matrix was constructed and inactive tests on a salt separation were carried out to produce the data required for the active tests. Fresh uranium metal prepared from the electrochemical reduction of U 3 O 8 powder was used as the surrogates of the spent nuclear fuel components which might be metallized by the electrochemical reduction process. LiCl, Li 2 O, Y 2 O 3 and SrCl 2 were selected as the components of the residual salts. Interactions between the salts and their influence on the separation of the residual salts were analyzed by differential scanning calorimetry (DSC) and thermogravimetry (TG). Eutectic melting of LiCl-Li 2 O and LiCl-SrCl 2 led to a melting point which was lower than that of a LiCl molten salt was observed. Residual salts were separated by a vaporization method. Co-vaporization of LiCl-Li 2 O and LiCl-SrCl 2 was achieved below temperatures which could make the uranium metal oxidation by Li 2 O possible. The salt vaporization rates at 950 .deg. C were measured as follows: LiCl-8 wt% Li 2 O > LiCl > LiCl-8 wt% SrCl 2 > SrCl 2

Electrochemical reduction behavior of U3O8 powder in a LiCl molten salt

International Nuclear Information System (INIS)

Jeong, Sang Mun; Shin, Ho-Sup; Hong, Sun-Seok; Hur, Jin-Mok; Do, Jae Bum; Lee, Han Soo

2010-01-01

The reduction path of the U 3 O 8 powder vol-oxidized at 1200 deg. C has been determined by a series of electrochemical experiments in a 1 wt.% Li 2 O/LiCl molten salt. Various reaction intermediates are observed by during electrolysis of U 3 O 8 . The formation of the metallic uranium is caused from two different reduction paths, a direct reduction of uranium oxide and an electro-lithiothermic reduction. As the uranium oxide is converted to the metallic uranium, the lithium metal is more actively formed in the cathode basket. The reducibility of the rare earth oxides with the U 3 O 8 powder has been tested by constant voltage electrolysis. The results suggest the advanced vol-oxidation could lead to the enhancement in the reducibility of the rare earth fission products.

Electric conductivity of salt melts containing KCL, KF and K2TaF7

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Stangrit, P.T.; Konstantinov, V.I.

1978-01-01

Given are electric conductivity measurement results depending on the temperature and composition of the molten KF-K 2 TaF 7 , KCl-K 2 TaF 7 systems and also melts close in their composition to industrial electrolytes, KCl-KF (in mass ratio of 2:1) with addition of K 2 TaF 7 up to 25 mass%. Presented are electric conductivity molecular isotherms of the KF-K 2 TaF 7 , KCl-K 2 TaF 7 systems at 800 deg C and specific electric conductivity dependence of KCl-KF-K 2 TaF 7 melts on K 2 TaF 7 composition at 800 deg C and 900 deg C. Proceeding from the shape of molecular and specific electric conductivity isotherms a conclusion is made about existence of the following tantalum-containing ions: TaF 7 2- , TaF 6 - and TaF 6 Cl 2- in the investigated melts

Preliminary Study on the High Temperature Transport System for Molten Salt

International Nuclear Information System (INIS)

Lee, S. H.; Lee, H. S.; Kim, J. G.

2012-01-01

Pyroprocessing technology is one of the the most promising technologies for the advanced fuel cycle with favorable economic potential and intrinsic proliferation-resistance. The electrorefining process, one of main processes is compos- ed of pyroprocess to recover the useful elements from spent fuel, is under development at the Korea Atomic Energy Research Institute as a sub process of the pyrochemical treatment of spent PWR fuel. High-temperature molten salt transport technologies are required because a molten salt should be transported from the electrorefiner to electrowiner after the electrorefining process. Therefore, in pyroprocessing technology, the development of high-temperature transport technologies for molten salt is a crucial prerequisite. However, there have been a few transport studies on high-temperature molten salt. In this study, an apparatus for suction transport experiments was designed and constructed for the development of high temperature molten salt transport technology. Suction transport experiments were performed using LiC-KCl eutectic salt

Estimation of key physical properties for LaCl_3 in molten eutectic LiCl–KCl by fitting cyclic voltammetry data to a BET-based electrode reaction kinetics model

International Nuclear Information System (INIS)

Samin, Adib; Wang, Zhonghang; Lahti, Erik; Simpson, Michael; Zhang, Jinsuo

2016-01-01

Understanding the electrochemical properties of rare earth elements is important for developing efficient techniques for separating rare earth elements from actinides recovered during the electrodeposition process. In this study the cyclic voltammetry for lanthanum in molten LiClKCl eutectic was recorded at 773 K for different scan rates and different bulk concentrations. A model accounting for mass transport, kinetics and adsorption was applied to analyze the experimental data via performing a nonlinear least squares fit. The results of the simulation are compared against the results of a conventional analysis of the cyclic voltammograms and against the existing literature. At the scan rates used, the reduction/oxidation process is quasi-reversible. The values of diffusivities derived from simulation were larger than the ones derived commonly using equations for diffusion-limited processes. However, those equations were derived based on an assumption of reversibility. This simulation-based approach may provide a more accurate option for analyzing systems that do not exhibit reversibility.

Volatility of components of saturated vapours of UCl4-CsCl and UCl4-LiCl molten mixtures

International Nuclear Information System (INIS)

Smirnov, M.V.; Kudyakov, V.Ya.; Salyulev, A.B.; Komarov, V.E.; Posokhin, Yu.V.; Afonichkin, V.K.

1979-01-01

The flow method has been used for measuring the volatility of the components from UCl 4 -CsCl and UCl 4 -LiCl melted mixtures containing 2.0, 5.0, 12.0, 25.0, 33.0, 50.0, 67.0, and 83.0 mol.% of UCl 4 within the temperature ranges of 903-1188 K and 740-1200 K, respectively. The chemical composition of saturated vapours above the melted salts has been determined. The melted mixtures in question exhibit negative deviation from ideal behaviour. Made was the conclusion about the presence in a vapour phase, along with monomeric UCl 4 , LiCl, CsCl and Li 2 Cl 2 , Cs 2 Cl 2 dimers of double compounds of the MeUCl 5 most probable composition. Their absolute contribution into a total pressure above the UCl 4 -CsCl melted mixtures is considerably smaller than above the UCl 4 -LiCl mixtures

The phase diagram of KNO3-KClO3

International Nuclear Information System (INIS)

Zhang Xuejun; Tian Jun; Xu Kangcheng; Gao Yici

2004-01-01

The binary phase diagram of KNO 3 -KClO 3 is studied by means of differential scanning calorimetry (DSC) and high-temperature X-ray diffraction. The limited solid solutions, K(NO 3 ) 1-x (ClO 3 ) x (0 3 ) 1-x (ClO 3 ) x (0.90 3 -based solid solutions and KClO 3 -based solid solutions phase, respectively. For KNO 3 -based solid solutions, KNO 3 ferroelectric phase can be stable from 423 to 223 K as a result of substituting of NO 3 by ClO 3 -radicals. The temperatures for solidus and liquidus have been determined based on limited solid solutions. Two models, Henrian solution and regular solution theory for KNO 3 -based (α) phase and KClO 3 -based (β) phase, respectively, are employed to reproduce solidus and liquidus of the phase diagram. The results are in good agreement with the DSC data. The thermodynamic properties for α and β solid solutions have been derived from an optimization procedure using the experimental data. The calculated phase diagram and optimized thermodynamic parameters are thermodynamically self-consistent

Chrono-potentiometry in molten chlorides. Application to the study of the electrochemical properties of uranium and plutonium in the LiCl-KCl eutectic; Chronopotentiometrie dans les chlorures fondus. Application a l'etude des proprietes electrochimiques de l'uranium et du plutonium dans l'eutectique LiCl-KCl

Energy Technology Data Exchange (ETDEWEB)

Leseur, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1969-05-01

Using solutions of cadmium chloride in the eutectic LiCl-KCl, a chrono-potentiometric method has been developed with a view to its application to the study of molten solutions. Particular attention has been paid to the choice of the indicator electrodes. The method makes it possible to analyze molten solutions quantitatively and to determine diffusion coefficients and their activation energies; it yields furthermore information about the nature and the behaviour of ionic species in solution. The method has been applied to the study of solutions of uranium and plutonium chloride in the eutectic LiCl-KCl. Linear chrono-amperometry has been used for studying these solutions quantitatively, but chrono-potentiometry, of which the theory is better developed, is better suited to a quantitative study. The results obtained have made it possible to determine the diffusion coefficients of the ions Cd{sup 2+}, U{sup 3+}, U{sup 4+} and U(IV) in the presence of F{sup -} and Pu{sup 3+} ions, as well as the activation energy of the diffusion coefficients. (author) [French] La mise au point de la chronopotentiometrie comme moyen d'etude des solutions fondues a ete effectuee avec des solutions de chlorure de cadmium dans l'eutectique LiCl-KCl. Le probleme du choix des electrodes indicatrices a ete particulierement etudie. La methode permet l'analyse quantitative des solutions fondues ainsi que la determination des coefficients de diffusion et de leurs energies d'activation: elle donne en outre des renseignements sur la nature et le comportement des especes ioniques en solution. Elle a ete appliquee a l'etude des solutions des chlorures d'uranium et de plutonium dans l'eutectique LiCl-KCl. La chronoamperometrie lineaire a ete utilisee pour l'etude qualitative de ces solutions, mais la chronopotentiometrie, dont la theorie est plus complete, convient mieux pour l'etude quantitative. Les resultats obtenus ont permis de determiner les

Purification of used eutectic (LiCl-KCl) salt electrolyte from pyroprocessing

Science.gov (United States)

Cho, Yung-Zun; Lee, Tae-Kyo; Eun, Hee-Chul; Choi, Jung-Hoon; Kim, In-Tae; Park, Geun-Il

2013-06-01

The separation characteristics of surrogate rare-earth fission products in a eutectic (LiCl-KCl) molten salt were investigated. This system is based on the eutectic salt used for the pyroprocessing treatment of used nuclear fuel (UNF). The investigation was performed using an integrated rare-earth separation apparatus comprising a precipitation reactor, a solid detachment device, and a layer separation device. To separate rare-earth fission products, a phosphate precipitation method using both Li3PO4 and K3PO4 as a precipitant was performed. The use of an equivalent phosphate precipitant composed of 0.408 molar ratio-K3PO4 and 0.592 molar ratio-Li3PO4 can preserve the original eutectic ratio, LiCl-0.592 molar ratio (or 45.2 wt%), as well as provide a high separation efficiency of over 99.5% under conditions of 550 °C and Ar sparging when using La, Nd, Ce, and Pr chlorides. The mixture of La, Nd, Ce, and Pr phosphate had a typical monoclinic (or monazite) structure, which has been proposed as a reliable host matrix for the permanent disposal of a high-level waste form. To maximize the reusability of purified eutectic waste salt after rare-earth separation, the successive rare-earth separation process, which uses both phosphate precipitation and an oxygen sparging method, were introduced and tested with eight rare-earth (Y, La, Ce, Pr, Nd, Sm, Eu and Gd) chlorides. In the successive rare-earth separation process, the phosphate reaction was terminated within 1 h at 550 °C, and a 4-8 h oxygen sparging time were required to obtain over a 99% separation efficiency at 700-750 °C. The mixture of rare-earth precipitates separated by the successive rare-earth separation process was found to be phosphate, oxychloride, and oxide. Through the successive rare-earth separation process, the eutectic ratio of purified salt maintained its original value, and impurity content including the residual precipitant of purified salt can be minimized.

Residual Salt Separation from the Metal Products Reduced in a LiCl-Li{sub 2}O Molten Salt

Energy Technology Data Exchange (ETDEWEB)

Hur, Jin Mok; Hong, Sun Seok; Kang, Dae Seung; Jeong, Meong Soo; Seo, Chung Seok

2006-02-15

The electrochemical reduction of spent nuclear fuel in a LiCl-Li{sub 2}O molten salt for the conditioning of spent nuclear fuel requires the separation of the residual salts from a reduced metal product after the reduction process. Considering the behavior of spent nuclear fuel during the electrochemical reduction process, a surrogate material matrix was constructed and inactive tests on a salt separation were carried out to produce the data required for the active tests. Fresh uranium metal prepared from the electrochemical reduction of U{sub 3}O{sub 8} powder was used as the surrogates of the spent nuclear fuel components which might be metallized by the electrochemical reduction process. LiCl, Li{sub 2}O, Y{sub 2}O{sub 3} and SrCl{sub 2} were selected as the components of the residual salts. Interactions between the salts and their influence on the separation of the residual salts were analyzed by differential scanning calorimetry (DSC) and thermogravimetry (TG). Eutectic melting of LiCl-Li{sub 2}O and LiCl-SrCl{sub 2} led to a melting point which was lower than that of a LiCl molten salt was observed. Residual salts were separated by a vaporization method. Co-vaporization of LiCl-Li{sub 2}O and LiCl-SrCl{sub 2} was achieved below temperatures which could make the uranium metal oxidation by Li{sub 2}O possible. The salt vaporization rates at 950 .deg. C were measured as follows: LiCl-8 wt% Li{sub 2}O > LiCl > LiCl-8 wt% SrCl{sub 2} > SrCl{sub 2}.

Estimation of key physical properties for LaCl{sub 3} in molten eutectic LiCl–KCl by fitting cyclic voltammetry data to a BET-based electrode reaction kinetics model

Energy Technology Data Exchange (ETDEWEB)

Samin, Adib [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, The Ohio State University, 201 W 19th Avenue, Columbus, OH 43210 (United States); Wang, Zhonghang [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, Metallurgical Engineering Department, University of Utah, Salt Lake City, UT 84112 (United States); Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); Lahti, Erik [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, The Ohio State University, 201 W 19th Avenue, Columbus, OH 43210 (United States); Simpson, Michael [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, Metallurgical Engineering Department, University of Utah, Salt Lake City, UT 84112 (United States); Zhang, Jinsuo, E-mail: zhang.3558@osu.edu [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, The Ohio State University, 201 W 19th Avenue, Columbus, OH 43210 (United States)

2016-07-15

Understanding the electrochemical properties of rare earth elements is important for developing efficient techniques for separating rare earth elements from actinides recovered during the electrodeposition process. In this study the cyclic voltammetry for lanthanum in molten LiClKCl eutectic was recorded at 773 K for different scan rates and different bulk concentrations. A model accounting for mass transport, kinetics and adsorption was applied to analyze the experimental data via performing a nonlinear least squares fit. The results of the simulation are compared against the results of a conventional analysis of the cyclic voltammograms and against the existing literature. At the scan rates used, the reduction/oxidation process is quasi-reversible. The values of diffusivities derived from simulation were larger than the ones derived commonly using equations for diffusion-limited processes. However, those equations were derived based on an assumption of reversibility. This simulation-based approach may provide a more accurate option for analyzing systems that do not exhibit reversibility.

Nickel based alloys for molten salt applications in pyrochemical reprocessing applications

International Nuclear Information System (INIS)

Ningshen, S.; Ravi Shankar, A.; Rao, Ch. Jagadeeswara; Mallika, C.; Kamachi Mudali, U.

2016-01-01

Pyrochemical reprocessing route is one of the best option for reprocessing of spent metallic nuclear fuel from future fast breeder in many countries, especially in the US (Integral fast reactor, IFR), Russia (Research Institute of Atomic Reactors, RIAR), Japan, Korea and India. This technology with intrinsic nuclear proliferation resistance is regarded as one of the most promising nuclear fuel cycle technologies of the next-generation. However, the selection of materials of construction for pyrochemical reprocessing plants is challenging because of the extreme environments, i.e., high radiation, corrosive molten salt (LiCl-KCl, LiCl-KCl-CsCl, KCl-NaCl-MgCl 2 , etc.), reactive molten metals, and high temperature. Efforts have been made to develop compatible materials for various unit operations like salt preparation, electrorefining, cathode processing and alloy casting in pyrochemical reprocessing. Nickel and its alloy are the candidate materials for salt purification exposed to molten LiCl-KCl under Cl 2 bubbling, in air or ultra high purity argon environment. In the present study, the corrosion behavior of candidate materials like Inconel 600, Inconel 625, Inconel 690 exposed to molten LiCl-KCl eutectic salt environment at 500 to 600 °C have been carried out. The surface morphology of the exposed samples and scales were examined by SEM/EDX and XRD. The weight loss results indicated that Inconel 600 and Inconel 690 offer better corrosion resistance compared to Inconel 625 in air and chlorine environment. Higher corrosion of Inconel 625 is attributed to development of Mo rich salt layers. However, Ni base alloys exhibited a decreasing trend of weight loss with increasing time of exposure and weight gain was observed under UHP Ar environment. The mechanism of corrosion of Ni base alloys appeared to be due to formation of Cr rich and Ni rich layers of Cr 2 O 3 , NiO and spinel oxides at the surface and subsequent spallation. Based on the present studies, Inconel 690

Corrosion Behavior of Superalloys in Hot Lithium Molten Salt

International Nuclear Information System (INIS)

Cho, Soo-Haeng; Hur, Jin-Mok; Seo, Chung-Seok; Park, Seoung-Won

2006-01-01

The Li-reduction process involves the chemical reduction of spent fuel oxides by liquid lithium metal in a molten LiCl salt bath at 650 .deg. C followed by a separate electrochemical reduction of lithium oxide (Li 2 O), which builds up in the salt bath. This process requires a high purity inert gas atmosphere inside remote hot cell nuclear facility to prevent unwanted Li oxidation and fires during the handling of chemically active Li metal. In light of the limitations of the Li-reduction process, a direct electrolytic reduction technology is being developed by KAERI to enhance process safety and economic viability. The electrolytic reduction of spent oxide fuel involves the liberation of oxygen in a molten LiCl electrolyte, which results in a chemically aggressive environment that is too corrosive for typical structural materials. Even so, the electrochemical process vessel must be resilient at ∼ 650 .deg. C in the presence of oxygen to enable high processing rates and an extended service life. But, the mechanism and the rate of the corrosion of metals in LiCl-Li 2 O molten salt under oxidation condition are not clear. In the present work, the corrosion behavior and corrosion mechanism of superalloys have been studied in the molten salt of LiCl-Li 2 O under oxidation condition

Potentiometric Sensor for Real-Time Monitoring of Multivalent Ion Concentrations in Molten Salt

International Nuclear Information System (INIS)

Zink, Peter A.; Jue, Jan-Fong; Serrano, Brenda E.; Fredrickson, Guy L.; Cowan, Ben F.; Herrmann, Steven D.; Li, Shelly X.

2010-01-01

Electrorefining of spent metallic nuclear fuel in high temperature molten salt systems is a core technology in pyroprocessing, which in turn plays a critical role in the development of advanced fuel cycle technologies. In electrorefining, spent nuclear fuel is treated electrochemically in order to effect separations between uranium, noble metals, and active metals, which include the transuranics. The accumulation of active metals in a lithium chloride-potassium chloride (LiCl-KCl) eutectic molten salt electrolyte occurs at the expense of the UCl3-oxidant concentration in the electrolyte, which must be periodically replenished. Our interests lie with the accumulation of active metals in the molten salt electrolyte. The real-time monitoring of actinide concentrations in the molten salt electrolyte is highly desirable for controlling electrochemical operations and assuring materials control and accountancy. However, real-time monitoring is not possible with current methods for sampling and chemical analysis. A new solid-state electrochemical sensor is being developed for real-time monitoring of actinide ion concentrations in a molten salt electrorefiner. The ultimate function of the sensor is to monitor plutonium concentrations during electrorefining operations, but in this work gadolinium was employed as a surrogate material for plutonium. In a parametric study, polycrystalline sodium beta double-prime alumina (Na-β(double p rime)-alumina) discs and tubes were subject to vapor-phase exchange with gadolinium ions (Gd3+) using a gadolinium chloride salt (GdCl3) as a precursor to produce gadolinium beta double-prime alumina (Gd-β(double p rime)-alumina) samples. Electrochemical impedance spectroscopy and microstructural analysis were performed on the ion-exchanged discs to determine the relationship between ion exchange and Gd3+ ion conductivity. The ion-exchanged tubes were configured as potentiometric sensors in order to monitor real-time Gd3+ ion concentrations in

FUSED SALT METHOD FOR COATING URANIUM WITH A METAL

Science.gov (United States)

Eubank, L.D.

1959-02-01

A method is presented for coating uranium with a less active metal such as Cr, Ni, or Cu comprising immersing the U in a substantially anhydrous molten solution of a halide of these less active metals in a ternary chloride composition which consists of selected percentages of KCl, NaCl and another chloride such as LiCl or CaCl/sub 2/.

Reduction behavior of UO{sub 2}{sup 2+} in molten LiCl–RbCl and LiCl–KCl eutectics by using tungsten

Energy Technology Data Exchange (ETDEWEB)

Nagai, Takayuki, E-mail: nagai.takayuki00@jaea.go.jp [Nuclear Fuel Cycle Engineering Lab., Japan Atomic Energy Agency, Muramatsu, Tokai, Naka, Ibaraki 319-1194 (Japan); Uehara, Akihiro; Fujii, Toshiyuki; Yamana, Hajimu [Research Reactor Institute, Kyoto University, Asashironishi, Kumatori, Sen-nan, Osaka 590-0494 (Japan)

2013-08-15

The reduction of uranium from UO{sub 2}{sup 2+} to UO{sub 2}{sup +} or U{sup 4+} in molten LiCl–RbCl and LiCl–KCl eutectics was examined by using tungsten and chlorine gas. Spectrophotometric technique was adopted to determine the concentration of uranium species. When tungsten was immersed into the LiCl–RbCl eutectic melt at 400 °C without supplying chlorine gas, 36% of the total weight of the hexavalent of UO{sub 2}{sup 2+} was reduced to the pentavalent of UO{sub 2}{sup +}. Under purging chlorine gas into the melt, 96% of UO{sub 2}{sup 2+} was reduced to the tetravalent of U{sup 4+}. Tungsten oxy-chloride of WOCl{sub 4} was produced via the reductions of UO{sub 2}{sup 2+}, which was volatized from the melt and adsorbed on the upper part of experimental cell. On the other hand, 84% of UO{sub 2}{sup 2+} in the LiCl–KCl eutectic melt at 500 °C was reduced to U{sup 4+} by using tungsten and chlorine gas.

Viscosity of melts of the system KCl-KBF4-K2TiF6

International Nuclear Information System (INIS)

Nguyen, D.K.; Danek, V.

1997-01-01

The viscosity of melts of the system KCl-KBF 4 -K 2 TiF 6 has been measured by means of the computerized torsional pendulum method. The viscosity of KCl is higher that of KBF 4 at the same temperature, most probably due to the substantial overheating of KBF 4 . In the ternary system the viscosity increases with increasing with increasing content of K 2 TiF 6 . Additivity of algorithms of viscosity was adopted as the ideal behaviour of the mixture. Negative deviations from such additive behaviour were found in the binary system KCl-KBF 4 probably due to the breaks of the weak B-Cl-B bridges caused by the excess of Cl - ions. Positive deviations from the ideal behaviour were found in the binaries KCl-K 2 TiF 6 and KBF 4 -K 2 TiF 6 due to the formation of larger anions TiF 6 Cl 3- and TiF 7 3- caused by the reactions K 2 TiF 6 (l) + KCl(l) = K 3 TiF 6 Cl(l) and KBF 4 (l) + K 2 TiF 6 (l) = K 3 TiF 7 (l) + BF 3 (g). Statistically significant ternary interaction confirmed that the above chemical reactions take place also in the ternary system. (authors)

Density of salt melts containing KF, KCl, K2TaF7 and Ta2O5

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Stangrit, P.T.; Konstantinov, V.I.

1978-01-01

The results of density measurements by hydrostatic weighing are given for molten K 2 TaF 7 - KF, K 2 TaF 7 -KCL, K 2 TaF 7 - KF - KCl and K 2 TaF 7 - KF - KCl - Ta 2 O 5 mixtures depending on their temperature and composition. The density of the last two systems was measured at compositions close to those of commercial electrolytes. The obtained specific volume - composition dependencies show that no interaction is taking place in the mixtures studied. It is, therefore, believed that, in the K 2 TaF 7 - KF melt, tantalum is mainly present as a complex TaF 7 2- ion, and, in the K 2 TaF 7 - KCl mlt, a certain amount of TaF 6 - ions may be formed along with TaF 7 2-

Fuel-coolant interactions in a shock-tube geometry

International Nuclear Information System (INIS)

Segev, A.; Henry, R.E.; Bankoff, S.G.

1978-01-01

Thermal interactions were studied in a shock tube configuration using different pairs of liquids. Large pressures were obtained for systems of water-Wood's metal and butanol-Wood's metal. Different types of interactions were observed, depending on the hot liquid temperature. It was found that thehydrodynamic component alone may account for the measured pressure in the lower temperature range. A combination of thermal and hydrodynamic interactions accounts for the pressures at high temperatures. Experiments with water and molten salt (LiCl + KCl) produced small scale explosions. All interactions were suppressed when driving pressure increased. (author)

Large-scale synthesis of Pb1-xLa xTiO3 ceramic powders by molten salt method

International Nuclear Information System (INIS)

Cai Zongying; Xing Xianran; Yu Ranbo; Liu Guirong; Xing Qifeng

2006-01-01

The ferroelectric perovskite type lanthanum doped lead titanate (PLT) ceramic powders were synthesized in one step with the starting materials of PbC 2 O 4 , La 2 O 3 and TiO 2 in NaCl-KCl molten salts in the temperature range of 700-950 deg. C. It was found that molten salt method was a large scale and easy preparation way to produce PLT powders with high dispersity. Tetragonal phase Pb 1-x La x TiO 3 ceramic powders were identified by XRD in the composition range 0 ≤ x ≤ 0.3 and mono-dispersed particles with spheric shape and less than 100 nm size were observed by SEM. The grain sizes of Pb 1-x La x TiO 3 ceramic powders increased with the increase of La content and decreased with calcination temperature. The grain growth progress and the possible reaction mechanism in molten salts and its influencing factors were discussed in this work. The grain growth process was the main influencing factor of the grain size, which depended on the solubility in the flux

Hot corrosion behavior of Ni-based superalloys in lithium molten salt

International Nuclear Information System (INIS)

Cho, Soo Haeng; Lim, Jong Ho; Chung, Joon Ho; Hur, Jin Mok; Seo, Chung Seok; Park, Seoung Won

2004-01-01

The Li-reduction process involves the chemical reduction of spent fuel oxides by liquid lithium metal in a molten LiCl salt bath at 650 .deg. C followed by a separate electrochemical reduction of lithium oxide (Li 2 O), which builds up in the salt bath. This process requires a high purity inert gas atmosphere inside remote hot cell nuclear facility to prevent unwanted Li oxidation and fires during the handling of chemically active Li metal. In light of the limitations of the Li-reduction process, a direct electrolytic reduction technology is being developed by KAERI to enhance process safety and economic viability. The electrolytic reduction of spent oxide fuel involves the liberation of oxygen in a molten LiCl electrolyte, which results in a chemically aggressive environment that is too corrosive for typical structural materials. Even so, the electrochemical process vessel must be resilient at 650 .deg. C in the presence of oxygen to enable high processing rates and an extended service life. But, the mechanism and the rate of the corrosion of metals in LiCl-Li 2 O molten salt under oxidation condition are not clear. In the present work, the corrosion behavior and corrosion mechanism of Ni-based superalloys have been studied in the molten salt of LiCl-Li 2 O under oxidation condition

Molten salt-mediated formation of g-C3N4-MoS2 for visible-light-driven photocatalytic hydrogen evolution

Science.gov (United States)

Li, Ni; Zhou, Jing; Sheng, Ziqiong; Xiao, Wei

2018-02-01

Construction of two-dimensional/two-dimensional (2D/2D) hybrid with well-defined composition and microstructure is a general protocol to achieve high-performance catalysts. We herein report preparation of g-C3N4-MoS2 hybrid by pyrolysis of affordable melamine and (NH4)2MoS4 in molten LiCl-NaCl-KCl at 550 °C. Molten salts are confirmed as ideal reaction media for formation of homogeneous hybrid. Characterizations suggest a strong interaction between g-C3N4 and MoS2 in the hybrid, which results in an enhanced visible-light-driven photocatalytic hydrogen generation of the hybrid with an optimal g-C3N4/MoS2 ratio. The present study highlights the merits of molten salt methods on preparation of 2D photocatalysts and provides a rational design of 2D/2D hybrid catalysts for advanced environmental and energy applications.

Volatility of components of saturated vapours of UCl/sub 4/-CsCl and UCl/sub 4/-LiCl molten mixtures

Energy Technology Data Exchange (ETDEWEB)

Smirnov, M V; Kudyakov, V Ya; Salyulev, A B; Komarov, V E; Posokhin, Yu V; Afonichkin, V K

1979-01-01

The flow method has been used for measuring the volatility of the components from UCl/sub 4/-CsCl and UCl/sub 4/-LiCl melted mixtures containing 2.0, 5.0, 12.0, 25.0, 33.0, 50.0, 67.0, and 83.0 mol.% of UCl/sub 4/ within the temperature ranges of 903-1188 K and 740-1200 K, respectively. The chemical composition of saturated vapours above the melted salts has been determined. The melted mixtures in question exhibit negative deviation from ideal behaviour. Made was the conclusion about the presence in a vapour phase, along with monomeric UCl/sub 4/, LiCl, CsCl and Li/sub 2/Cl/sub 2/, Cs/sub 2/Cl/sub 2/ dimers of double compounds of the MeUCl/sub 5/ most probable composition. Their absolute contribution into a total pressure above the UCl/sub 4/-CsCl melted mixtures is considerably smaller than above the UCl/sub 4/ -LiCl mixtures.

Electrochemical deposition of La-Mg alloys in LaCl3-MgCl2-KCl system with molten salt electrolysis process

Directory of Open Access Journals (Sweden)

Sahoo Kumar D.

2014-01-01

Full Text Available La-Mg alloys of different compositions were prepared by electrolysis of LaCl3-MgCl2-KCl melts. Different phases of La-Mg alloys were characterized by X-ray diffraction (XRD and Scanning Electron Microscopy (SEM. Energy dispersive spectrometry (EDS and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES analyses showed that chemical compositions of La-Mg alloys were consistent with phase structures of XRD pattern, and magnesium content in the alloy could be controlled by electrolysis parameters. The effects of various process parameters such as concentration of magnesium chloride in the bath, temperature of electrolysis and cathode current density on the current efficiency have been investigated. A maximum current efficiency of 85% and yield of 80% was obtained from the bath at 12.5A/cm2 current density at an operating temp 850°C.

Molten Salt-Based Growth of Bulk GaN and InN for Substrates

Energy Technology Data Exchange (ETDEWEB)

Waldrip, Karen Elizabeth [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Power Sources Technology Dept.; Tsao, Jeffrey Yeenien [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Energy Sciences Dept.; Kerley, Thomas M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Materials Sciences Dept.

2006-09-01

An atmospheric pressure approach to growth of bulk group III-nitrides is outlined. Native III-nitride substrates for optoelectronic and high power, high frequency electronics are desirable to enhance performance and reliability of these devices; currently, these materials are available in research quantities only for GaN, and are unavailable in the case of InN. The thermodynamics and kinetics of the reactions associated with traditional crystal growth techniques place these activities on the extreme edges of experimental physics. The technique described herein relies on the production of the nitride precursor (N^3-) by chemical and/or electrochemical methods in a molten halide salt. This nitride ion is then reacted with group III metals in such a manner as to form the bulk nitride material. The work performed during the period of funding (July 2004-September 2005) focused on the initial measurement of the solubility of GaN in molten LiCl as a function of temperature, the construction of electrochemical cells, the modification of a commercial glove box (required for handling very hygroscopic LiCl), and on securing intellectual property for the technique.

Study of the Electrolytic Reduction of Uranium Oxide in LiCl-Li2O Molten Salts with an Integrated Cathode Assembly

International Nuclear Information System (INIS)

Park, Sung Bin; Seo, Chung Seok; Kang, Dae Seung; Kwon, Seon Gil; Park, Seong Won

2005-01-01

The electrolytic reduction of uranium oxide in a LiCl-Li 2 O molten salt system has been studied in a 10 g U 3 O 3 /batch-scale experimental apparatus with an integrated cathode assembly at 650 .deg. C. The integrated cathode assembly consists of an electric conductor, the uranium oxide to be reduced and the membrane for loading the uranium oxide. From the cyclic voltammograms for the LiCl-3 wt% Li 3 O system and the U 3 O 3 -LiCl-3 wt% Li 2 O system according to the materials of the membrane in the cathode assembly, the mechanisms of the predominant reduction reactions in the electrolytic reactor cell were to be understood; direct and indirect electrolytic reduction of uranium oxide. Direct and indirect electrolytic reductions have been performed with the integrated cathode assembly. Using the 325-mesh stainless steel screen the uranium oxide failed to be reduced to uranium metal by a direct and indirect electrolytic reduction because of a low current efficiency and with the porous magnesia membrane the uranium oxide was reduced successfully to uranium metal by an indirect electrolytic reduction because of a high current efficiency.

Electrochemical study of uranium cations in LiCl-KCl melt using a rotating disk electrode

Energy Technology Data Exchange (ETDEWEB)

Bae, Sang-Eun; Kim, Dae-Hyun; Kim, Jong-Yoon; Park, Tae-Hong; Cho, Young Hwan; Yeon, Jei-Won; Song, Kyuseok [Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute,989-111 Daedeok-daero, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)

2013-07-01

A rotating disk electrode (RDE) measurement technique was employed to investigate the electrochemical REDOX reactions of actinide (An) and lanthanide (Ln) ions in LiCl-KCl molten salt. By using RDE, it is possible to access more exact values of the diffusion coefficient, Tafel slope, and exchange current density. In this work, we constructed RDE setup and electrodes for RDE measurements in high temperature molten salt and measured the electrochemical parameters of the An and Ln ions. The RDE setup is composed of a Pine model MSRX rotator equipped with a rod type of W electrode. The active electrode area was confined to the planar part of the W rod by making meniscus at the LiCl-KCl melt surface.

A Study on Electrochemical Reduction of Rare Earth Oxides in Molten LiCl-Li2O Salt

International Nuclear Information System (INIS)

Lee, Min Woo; Jeong, Sang Mun; Lee, See Hoon; Sohn, Jung Min

2016-01-01

In this study, the electrochemical reduction of RE 2 O 3 (RE = Nd or Ce) has been conducted via co-reduction NiO to increase the reduction degree of the rare earth oxides in molten molten LiCl containing 1wt% Li 2 O. The electrochemical reduction behavior of the mixed RE 2 O 3 -NiO oxide has been investigated and the reduction path of RE 2 O 3 has been proposed. An electorchemical spent fuel processing technology, pyroprocessing, has been developed for recycling of spent fuel to be applied to a sodium-cooled fast reactor. The spent fuel is reduced in the oxide reduction process. It is well known that the rare earth oxides are hardly reduced due to their electrochemical and thermodynamic stability. The rare earth oxides unreduced in the reduction process can cause problems via reaction with UCl 3 in the electrorefiner. To tackle those problems, the electrochemical reduction of rare earth oxide has been conducted via co-reduction of NiO in LiCl molten salt containing 1 wt% Li 2 O. The reduction of the oxide mixture starts from the reduction of NiO to Ni, followed by that of RE 2 O 3 on the produced Ni to form intermetallic RENi 5 . The mixed oxide pellets were successfully reduced to the RENi5 alloy by constant electrolysis at 3.0 V at 650 .deg. C. The crucial aspect to these results is that the thermodynamically stable rare-earth oxide, Nd 2 O 3 was successfully converted to the metal in the presence of NiO.

Galvanic reduction of uranium(III) chloride from LiCl-KCl eutectic salt using gadolinium metal

Science.gov (United States)

Bagri, Prashant; Zhang, Chao; Simpson, Michael F.

2017-09-01

The drawdown of actinides is an important unit operation to enable the recycling of electrorefiner salt and minimization of waste. A new method for the drawdown of actinide chlorides from LiCl-KCl molten salt has been demonstrated here. Using the galvanic interaction between the Gd/Gd(III) and U/U(III) redox reactions, it is shown that UCl3 concentration in eutectic LiCl-KCl can be reduced from 8.06 wt.% (1.39 mol %) to 0.72 wt.% (0.12 mol %) in about an hour via plating U metal onto a steel basket. This is a simple process for returning actinides to the electrorefiner and minimizing their loss to the salt waste stream.

Electrochemical reduction of lanthanum trichloride in a molten equimolar mixture of sodium and potassium chlorides

Energy Technology Data Exchange (ETDEWEB)

Glagolevskaya, A.L.; Kuznetsov, S.A.; Polyakov, E.G.; Stangrit, P.T.

1987-09-20

The authors used linear voltamperometry for the investigation of the mechanism for the cathodic reduction of lanthanum. The mechanism for the cathodic reduction of lanthanum chloride in molten equimolar NaCl-KCl may be seen as consisting of a slow irreversible electrode reaction with a subsequent rapid irreversible chemical reaction. Lanthanum ions in a lower oxidation state were not found upon the prolonged maintenance of metallic lanthanum in molten NaCl-KCl-LaCl/sub 3/. Only an increase in the concentration of lanthanum(III) chloride in the melt was noted. The appearance of oxygen anions in the melt does not lead to a change in the mechanism of the cathodic reduction of lanthanum chloride but reduces the concentration of this chloride due to the formation of lanthanum oxochloride which is insoluble in the melt.

A systemic study of stepwise chlorination-chemical vapor transport characteristics of pure rare earth oxides from Sc2O3 to Lu2O3 mediated by alkaline chlorides as complex former

International Nuclear Information System (INIS)

Sun Yanhui; He Peng; Chen Huani

2007-01-01

A systematic study has been carried out for the stepwise chlorination-chemical vapor transport (SC-CVT) characteristics of pure rare earth oxides from Sc 2 O 3 to Lu 2 O 3 mediated by the vapor complexes KLnCl 4 and NaLnCl 4 (Ln = Sc, Y and La-Lu) used NaCl and KCl as complex former, respectively. The results showed that the SC-CVT characteristics are similarly for NaCl and KCl as complex former, the main deposition temperature of the rare earth chlorides LnCl 3 is in the increasing order ScCl 3 3 3 , and then with a systematically decreasing trend from the early lanthanide chlorides to the end one. The results also showed that the total transported amount of the produced chlorides is YCl 3 > ScCl 3 , and they are much higher than that of most lanthanoid chlorides. For lanthanoids, the total transported amount of chloride increases systematically from the early lanthanoid chlorides to the end one except for EuCl 3 and GdCl 3 mediated by KCl and NaCl as complex former, respectively, which showed the divergence effect of Gd in the total transport efficiency. But there are some differences in SC-CVT characteristics of pure rare earth oxide mediated by KCl and NaCl as complex former, that is the main deposition temperature region for the same rare earth element was lower for KCl than that for NaCl as complex former except for LaCl 3 , CeCl 3 , YbCl 3 and LuCl 3 , while the total transport amount of rare earth chloride for KCl as complex former is higher than that for NaCl except for LaCl 3 and EuCl 3 . More over, the discussion was carried out for Sc and Y on the one hand and the lanthanides contain 4f electron as another hand based on the 4f electron hybridization assumption. Further more, the transport characteristics of rare earth oxides with alkaline chlorides as complex former in this study were compared to that with AlCl 3 as complex former

Hot electrons and the approach to metallic behavior in Kx(KCl)1-x

NARCIS (Netherlands)

Silvestrelli, P.L.; Alavi, A.; Parrinello, M.; Frenkel, D.

1996-01-01

The approach to the metallic phase of molten Kx(KCl)1-x mixtures is studied using ab initio molecular dynamics based on finite-temperature density functional theory. The finite electronic temperature is found to result in new and unexpected effects. In particular, we observe a thermally induced

Thorium Molten Salt Nuclear Energy Synergetic System (THORIMS-NES)

International Nuclear Information System (INIS)

Yoshioka, Ritsuo; Mitachi, Koshi

2013-01-01

The authors have been promoting nuclear energy technology based on thorium molten salt as Thorium Molten Salt Nuclear Energy Synergetic System (THORIMS-NES). This system is a combination of fission power reactor of Molten Salt Reactor (MSR), and Accelerator Molten Salt Breeder (AMSB) for production of fissile 233 U with connecting chemical processing facility. In this paper, concept of THORIMS-NES, advantages of thorium and molten salt recent MSR design results such as FUJI-U3 using 233 U fuel, FUJI-Pu, large sized super-FUJI, pilot plant miniFUJI, AMSB, and chemical processing facility are described. (author)

Application of lithium in molten-salt reduction processes

International Nuclear Information System (INIS)

Gourishankar, K. V.

1998-01-01

Metallothermic reductions have been extensively studied in the field of extractive metallurgy. At Argonne National Laboratory (ANL), we have developed a molten-salt based reduction process using lithium. This process was originally developed to reduce actinide oxides present in spent nuclear fuel. Preliminary thermodynamic considerations indicate that this process has the potential to be adapted for the extraction of other metals. The reduction is carried out at 650 C in a molten-salt (LiCl) medium. Lithium oxide (Li 2 O), produced during the reduction of the actinide oxides, dissolves in the molten salt. At the end of the reduction step, the lithium is regenerated from the salt by an electrowinning process. The lithium and the salt from the electrowinning are then reused for reduction of the next batch of oxide fuel. The process cycle has been successfully demonstrated on an engineering scale in a specially designed pyroprocessing facility. This paper discusses the applicability of lithium in molten-salt reduction processes with specific reference to our process. Results are presented from our work on actinide oxides to highlight the role of lithium and its effect on process variables in these molten-salt based reduction processes

A Study on Electrochemical Reduction of Rare Earth Oxides in Molten LiCl-Li{sub 2}O Salt

Energy Technology Data Exchange (ETDEWEB)

Lee, Min Woo; Jeong, Sang Mun; Lee, See Hoon [Chungbook National University, Chungju (Korea, Republic of); Sohn, Jung Min [Chonbuk National University, Jeonju (Korea, Republic of)

2016-05-15

In this study, the electrochemical reduction of RE{sub 2}O{sub 3} (RE = Nd or Ce) has been conducted via co-reduction NiO to increase the reduction degree of the rare earth oxides in molten molten LiCl containing 1wt% Li{sub 2}O. The electrochemical reduction behavior of the mixed RE{sub 2}O{sub 3}-NiO oxide has been investigated and the reduction path of RE{sub 2}O{sub 3} has been proposed. An electorchemical spent fuel processing technology, pyroprocessing, has been developed for recycling of spent fuel to be applied to a sodium-cooled fast reactor. The spent fuel is reduced in the oxide reduction process. It is well known that the rare earth oxides are hardly reduced due to their electrochemical and thermodynamic stability. The rare earth oxides unreduced in the reduction process can cause problems via reaction with UCl{sub 3} in the electrorefiner. To tackle those problems, the electrochemical reduction of rare earth oxide has been conducted via co-reduction of NiO in LiCl molten salt containing 1 wt% Li{sub 2}O. The reduction of the oxide mixture starts from the reduction of NiO to Ni, followed by that of RE{sub 2}O{sub 3} on the produced Ni to form intermetallic RENi{sub 5}. The mixed oxide pellets were successfully reduced to the RENi5 alloy by constant electrolysis at 3.0 V at 650 .deg. C. The crucial aspect to these results is that the thermodynamically stable rare-earth oxide, Nd{sub 2}O{sub 3} was successfully converted to the metal in the presence of NiO.

Meltability in system of K2TaF7-NaF-NaCl-KCl

International Nuclear Information System (INIS)

Kartsev, V.E.; Kovalev, F.V.; Korshunov, B.G.

1975-01-01

Thermographic and visual-polythermal techniques were used to study the meltability in K 2 TaF 7 -NaF-NaCl-KCl system. The tetrahedron-forming sections NaF-NaCl-K 2 TaF 7 xKCl and NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl divide the concentration tetrahedron into three particular tetrahedra: NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl-K 2 TaF 7 , NaF-NaCl-K 2 TaF 7 xKCl-2K 2 TaF 7 xaCl, and NaF-NaCl-KCl-K 2 TaF 7 xKCl. Non-variant equilibrium points in all of the particular four-component systems have been determined

Testing of pyrochemical centrifugal contactors

International Nuclear Information System (INIS)

Chow, L.S.; Carls, E.L.; Basco, J.K.; Johnson, T.R.

1996-01-01

A centrifugal contactor that performs oxidation and reduction exchange reactions between molten metals and salts at 500 degrees Centigrade has been tested successfully at Argonne National Laboratory (ANL). The design is based on contactors for aqueous- organic systems operation near room temperature. In tests to demonstrate the performance of the pyrocontactor, cadmium and LICl-KCl eutectic salt were the immiscible solvent phases, and rare earths were the distributing solutes. The tests showed that the pyrocontactor mixed and separated the phases well, with stage efficiencies approaching 99% at rotor speeds near 2700 rpm. The contactor ran smoothly and reliably over the entire range of speeds that was tested

Corrosion Behavior of a Surface Modified Inconel 713LC in a Hot Lithium Molten Salt

International Nuclear Information System (INIS)

Cho, Soo Haeng; Lim, Jong Ho; Seo, Chung Seok; Jung, Ki Jung; Park, Seoung Won

2005-01-01

The Li-reduction process involves the chemical reduction of spent fuel oxides by liquid lithium metal in a molten LiCl salt bath at 650 .deg. C followed by a separate electrochemical reduction of the lithium oxide (Li 2 O), which builds up in the salt bath. This process requires a high purity inert gas atmosphere inside a remote hot cell nuclear facility to prevent an unwanted Li oxidation and fires during the handling of the chemically active Li metal. In light of the limitations of the Li-reduction process, a direct electrolytic reduction technology is being developed by KAERI to enhance the process safety and economic viability. The electrolytic reduction of spent oxide fuel involves the liberation of the oxygen in a molten LiCl electrolyte, which results in a chemically aggressive environment that is too corrosive for typical structural materials. Even so, the electrochemical process vessel must be resilient at 650 .deg. C in the presence of oxygen to enable high processing rates and an extended service life. But, the mechanism and the rate of the corrosion of the metals in a LiCl-Li 2 O molten salt under an oxidation condition are not clear. In the present work, the corrosion behavior and corrosion mechanism of a surface modified Inconel 713LC have been studied in the molten salt of LiCl-Li 2 O under an oxidation condition

The system K2NbF7-K2TiF6-KCl

International Nuclear Information System (INIS)

Kamenskaya, L.A.; Matveev, A.M.

1984-01-01

Using visual-polythermal and thermographical methods the ternary system K 2 NbF 7 -K 2 TiE 6 -KCl has been studied. Crystallization fields of initial components and the field of solid solutions of double compounds K 3 NbClF 7 and K 3 TiClF 6 are outlined. Ternary eutectics at 654 deg C, having the composition K 2 NbF 6 -41, K 2 TiP 6 -41, KCl-18 mol.%, is determined. Potassium fluoroniobate and fluorotitanate form continuous solid solutions unstable in the presence of the third component, potassium chloride

Extraction of lanthanide elements and bismuth in molten lithium chloride-liquid bismuth-lithium alloy system

International Nuclear Information System (INIS)

Harada, Makoto; Adachi, Motonari; Kai, Yuichi; Koike, Kenichi

1987-01-01

The equilibrium distributions of neodymium and samarium between molten LiCl and liquid Bi-Li alloy were measured in a wide range of Li-mole fraction in the alloy phase, X Li . These lanthanide elements were extracted through redox reactions. In high X Li range, X Li > 0.03, the distributions of neodymium and bismuth in the salt phase increased markedly. The anomalous increase is attributed to the formation of the compound comprized of Nd, Li, Bi and oxygen in the salt phase. The reaction processes in samarium and neodymium were very fast and the extraction rates are controlled by the diffusion processes of the solutes and metallic lithium. (author)

Nonmetal-metal transition in metal–molten-salt solutions

NARCIS (Netherlands)

Silvestrelli, P.-L.; Alavi, A.; Parrinello, M.; Frenkel, D.

1996-01-01

The method of ab initio molecular dynamics, based on finite-temperature density-functional theory, is used to study the nonmetal-metal transition in two different metal–molten-salt solutions, Kx(KCl)1-x and Nax(NaBr)1-x. As the excess metal concentration is increased the electronic density becomes

Thermodynamics of HfCl4-KCl molten mixtures containing HfCl4 up to 33.3 mol. per cent

International Nuclear Information System (INIS)

Smirnov, M.V.; Salyulev, A.B.; Kudyakov, V.Ya.

1980-01-01

Based on measurements of saturated vapour pressure in components of melted mixtures of HfCl 4 -KCl, depending on temperature and concentration, calculated are the results of changes in activity coefficients of hafnium tetrachloride and potassium chloride on transition from diluted solutions, where the Henry law is met, to those concentrated where the law is disobeyed. Growth in the activity coefficient of HfCl 4 is due to dissociation of complex groups of HfCl 6 2- into complexes with a lesser number of ligands and decreasing relative binding energy of Hf 4+ -Cl - there. In this case, marked changes take place in partial enthalpy and entropy of hafnium tetrachloride mixing. Similar dependences are observed for potassium chloride, but they are expressed considerably weaker. Evaporation enthalpy and entropy are calculated for HfCl 4 and KCl monomers from their melted mixtures of various concentrations

Converting hcp Mg-Al-Zn alloy into bcc Mg-Li-Al-Zn alloy by electrolytic deposition and diffusion of reduced lithium atoms in a molten salt electrolyte LiCl-KCl

International Nuclear Information System (INIS)

Lin, M.C.; Tsai, C.Y.; Uan, J.Y.

2007-01-01

A body-centered cubic (bcc) Mg-12Li-9Al-1Zn (wt.%) alloy was fabricated in air by electrolysis from LiCl-KCl molten salt at 500 deg. C. Electrolytic deposition of Li atoms on cathode (Mg-Al-Zn alloy) and diffusion of the Li atoms formed the bcc Mg-Li-Al-Zn alloy with 12 wt.% Li and only 0.264 wt.% K. Low K concentration in the bcc Mg alloy strip after the electrolysis process resulted from 47% atomic size misfit between K and Mg atoms and low solubility of K in Mg matrix

Thorium valency in molten alkali halides in equilibrium with metallic thorium

International Nuclear Information System (INIS)

Smirnov, M.V.; Kudyakov, V.Ya.

1983-01-01

Metallic thorium is shown to corrode in molten alkali halides even in the absence of external oxidizing agents, alkali cations acting as oxidizing agents. Its corrosion rate grows in the series of alkali chlorides from LiCl to CsCl at constant temperature. Substituting halide anions for one another exerts a smaller influence, the rate rising slightly in going from chlorides to bromides and iodides, having the same alkali cations. Thorium valency is determined coulometrically, the metal being dissolved anodically in molten alkali halides and their mixtures. In fluoride melts it is equal to 4 but in chloride, bromide and iodide ones, as a rule, it has non-integral values between 4 and 2 which diminish as the temperature is raised, as the thorium concentration is lowered, as the radii of alkali cations decrease and those of halide anions increase. The emf of cells Th/N ThHlsub(n) + (1-N) MHl/MHl/C, Hlsub(2(g)) where Hl is Cl, Br or I, M is Li, Na, K, Cs or Na + K, and N < 0.05, is measured as a function of concentration at several temperatures. Expressions are obtained for its concentration dependence. The emf grows in the series of alkali chlorides from LiCl to CsCl, other conditions being equal. (author)

Inversion of the calcium isotope separation at an ion exchanger resin by variation of the LiCl electrolyte concentration

International Nuclear Information System (INIS)

Heumann, K.G.; Kloeppel, H.; Sigl, G.

1982-01-01

The calcium isotope separation at a strongly acidic exchanger resin as a function of the concentration of a LiCl solution is investigated in column experiments. Whereas an enrichment of the heavier calcium isotopes in the solution phase is found with a 3 M LiCl solution, an inverse effect is obtained with 8 M and 12 M LiCl solutions. The separation effect epsilon for the 12 M solution is found to be the highest calcium enrichment in a system without a complexing agent. The results are compared with those for other electrolyte solutions and can be explained by the anion/cation interactions. (orig.)

Experimental Study of Codeposition Electrochemistry Using Mixtures of ScCl₃ and YCl₃ in LiCl-KCl Eutectic Salt at 500°C

Energy Technology Data Exchange (ETDEWEB)

Shaltry, Michael R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yoo, Tae-Sic [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fredrickson, Guy L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2017-09-12

Cyclic voltammetry and chronopotentiometry tests were applied to molten LiCl-KCl eutectic at 500 °C including amounts of ScCl₃ and YCl₃. The purpose of the testing was to observe the effect of applied electrical current on the codeposition of scandium and yttrium, which were chosen as surrogate elements for uranium and plutonium, respectively. Features of the work were to vary the concentration of ScCl₃ (at relatively low concentrations) as well as varying the applied current, all with a fixed concentration of YCl₃. Results of the experiments could provide insight of uranium electrorefining and may provide evidence, which suggests the electrorefiner could be operated at lower UCl₃ concentration whereby codeposition (U and Pu) could be more effectively controlled.

Molecular dynamics calculation of shear viscosity for molten salt

International Nuclear Information System (INIS)

Okamoto, Yoshihiro; Yokokawa, Mitsuo; Ogawa, Toru

1993-12-01

A computer program of molecular dynamics simulation has been made to calculate shear viscosity of molten salt. Correlation function for an off-diagonal component of stress tensor can be obtained as the results of calculation. Shear viscosity is calculated by integration of the correlation function based on the Kubo-type formula. Shear viscosities for a molten KCl ranging in temperature from 1047K to 1273K were calculated using the program. Calculation of 10 5 steps (1 step corresponds to 5 x 10 -15 s) was performed for each temperature in the 216 ions system. The obtained results were in good agreement with the reported experimental values. The program has been vectorized to achieve a faster computation in supercomputer. It makes possible to calculate the viscosity using a large number of statistics amounting to several million MD steps. (author)

Characteristics of dechlorination for LiCl salt by the surface temperature-controlled reactor

Energy Technology Data Exchange (ETDEWEB)

Cho, In Hak [Chungnam National University, Daejeon (Korea, Republic of); Park, Hwan Seo; Ahn, Soo Na; Eun, Hee Chul; Kim, In Tae; Cho, Yong Jun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-05-15

Molten salt waste is generated from a pyrochemical process to separate reusable U and TRU elements from a spent nuclear fuel. The spent lithium chloride waste is highly soluble in water and contains volatile radioactive elements such as Cs. However, these wastes are difficult to directly immobilize into durable matrix such as glass or ceramic wasteform for final disposal. ANL(Argonne National Laboratory) suggested the conversion of metal chloride into a sodalite for the immobilization of a chloride waste, glass-bonded sodalite, which was fabricated at about 915 .deg. C after mixing the salt-loaded zeolite and borosilicate glass powder. Although this wasteform shows high leach-resistance, the waste volume greatly increases. The previous study was to treat metal chloride wastes by using SAP(SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}) materials. By using this method, the final waste volume reduced and leach-resistance was good. In this study, characteristics of dechlorination reaction of LiCl with an inorganic composite, SAP, was investigated by using a specific surface temperature-controlled reactor

The molten salt reactors (MSR) pyro chemistry and fuel cycle for innovative nuclear systems

International Nuclear Information System (INIS)

Brossard, Ph.; Garzenne, C.; Mouney, H.

2002-01-01

In the frame of the studies on next generation nuclear systems, and especially for the molten salt reactors and for the integrated fuel cycle (as IFR), the fuel cycle constraints must be taken into account in the preliminary studies of the system to improve the cycle and reactor optimisation. Among the purposes for next generation nuclear systems, sustainability and waste (radio-toxicity and mass) management are important goals. These goals imply reprocessing and recycling strategies. The objectives of this workshop are to present and to share the different strategies and scenarios, the needs based on these scenarios, the experimental facilities available today or in the future and their capabilities, the needs for demonstration. It aims at: identifying the needs for fuel cycle based on solid fuel or liquid fuel, and especially, the on-line reprocessing or clean up for the molten salt reactors; assessing the state-of-the-art on the pyro-chemistry applied to solid fuel and to present the research activities; assessing the state-of-the-art on liquid fuels (or others), and to present the research activities; expressing the R and D programs for pyro-chemistry, molten salt, and also to propose innovative processes; and proposing some joint activities in the frame of GEDEON and PRACTIS programs. This document brings together the transparencies of 18 contributions dealing with: scenario studies with AMSTER concept (Scenarios, MSR, breeders (Th) and burners); fuel cycle for innovative systems; current reprocessing of spent nuclear fuel (SNF) in molten salts (review of pyro-chemistry processes (non nuclear and nuclear)); high temperature NMR spectroscopies in molten salts; reductive extraction of An from molten fluorides (salt - liquid metal extraction); electrochemistry characterisation; characterisation with physical methods - extraction coefficient and kinetics; electrolytic extraction; dissolution-precipitation of plutonium in the eutectic LiCl-KCl (dissolution and

Modeling Solute Thermokinetics in LiCI-KCI Molten Salt for Nuclear Waste Separation

Energy Technology Data Exchange (ETDEWEB)

Morgan, Dane; Eapen, Jacob

2013-10-01

Recovery of actinides is an integral part of a closed nuclear fuel cycle. Pyrometallurgical nuclear fuel recycling processes have been developed in the past for recovering actinides from spent metallic and nitride fuels. The process is essentially to dissolve the spent fuel in a molten salt and then extract just the actinides for reuse in a reactor. Extraction is typically done through electrorefining, which involves electrochemical reduction of the dissolved actinides and plating onto a cathode. Knowledge of a number of basic thermokinetic properties of salts and salt-fuel mixtures is necessary for optimizing present and developing new approaches for pyrometallurgical waste processing. The properties of salt-fuel mixtures are presently being studied, but there are so many solutes and varying concentrations that direct experimental investigation is prohibitively time consuming and expensive (particularly for radioactive elements like Pu). Therefore, there is a need to reduce the number of required experiments through modeling of salt and salt-fuel mixture properties. This project will develop first-principles-based molecular modeling and simulation approaches to predict fundamental thermokinetic properties of dissolved actinides and fission products in molten salts. The focus of the proposed work is on property changes with higher concentrations (up to 5 mol%) of dissolved fuel components, where there is still very limited experimental data. The properties predicted with the modeling will be density, which is used to assess the amount of dissolved material in the salt; diffusion coefficients, which can control rates of material transport during separation; and solute activity, which determines total solubility and reduction potentials used during electrorefining. The work will focus on La, Sr, and U, which are chosen to include the important distinct categories of lanthanides, alkali earths, and actinides, respectively. Studies will be performed using LiCl-KCl salt

Preliminary study of the electrolysis of aluminum sulfide in molten salts

Energy Technology Data Exchange (ETDEWEB)

Minh, N.Q.; Loutfy, R.O.; Yao, N.P.

1983-02-01

A preliminary laboratory-scale study of the electrolysis of aluminum sulfide in molten salts investigated the (1) solubility of Al/sub 2/S/sub 3/ in molten salts, (2) electrochemical behavior of Al/sub 2/S/sub 3/, and (3) electrolysis of Al/sub 2/S/sub 3/ with the determination of current efficiency as a function of current density. The solubility measurements show that MgCl/sub 2/-NaCl-KCl eutectic electrolyte at 1023 K can dissolve up to 3.3 mol % sulfide. The molar ratio of sulfur to aluminum in the eutectic is about one, which suggests that some sulfur remains undissolved, probably in the form of MgS. The experimental data and thermodynamic calculations suggest that Al/sub 2/S/sub 3/ dissolves in the eutectic to form AlS/sup +/ species in solution. Addition of AlCl/sub 3/ to the eutectic enhances the solubility of Al/sub 2/S/sub 3/; the solubility increases with increasing AlCl/sub 3/ concentration. The electrode reaction mechanism for the electrolysis of Al/sub 2/S/sub 3/ was elucidated by using linear sweep voltammetry. The cathodic reduction of aluminum-ion-containing species to aluminum proceeds by a reversible, diffusion-controlled, three-electron reaction. The anodic reaction involves the two-electron discharge of sulfide-ion-containing species, followed by the fast dimerization of sulfur atoms to S/sub 2/. Electrolysis experiments show that Al/sub 2/S/sub 3/ dissolved in molten MgCl/sub 2/-NaCl-KCl eutectic or in eutectic containing AlCl/sub 3/ can be electrolyzed to produce aluminum and sulfur. In the eutectic at 1023 K, the electrolysis can be conducted up to about 300 mA/cm/sup 2/ for the saturation solubility of Al/sub 2/S/sub 3/. Although these preliminary results are promising, additional studies are needed to elucidate many critical operating parameters before the technical potential of the electrolysis can be accurately assessed. 20 figures, 18 tables.

Molten salt synthesis of lead lanthanum zirconate titanate ceramic powders

International Nuclear Information System (INIS)

Cai Zongying; Xing Xianran; Li Lu; Xu Yeming

2008-01-01

Lead lanthanum zirconate titanate (Pb 0.95 La 0.03 )(Zr 0.52 Ti 0.48 )O 3 (PLZT) was synthesized by one step molten salt method with the starting materials of PbC 2 O 4 , La 2 O 3 , ZrO(NO 3 ) 2 .2H 2 O and TiO 2 in the NaCl-KCl eutectic mixtures in the temperature range of 700-1000 deg. C. The single phase of (Pb 0.95 La 0.03 )(Zr 0.52 Ti 0.48 )O 3 powders was prepared at a temperature as low as 850 deg. C for 5 h. The effects of process parameters, such as soaking temperature and time, salt species, and the amount of flux with respect to the starting materials were investigated. The growth process of the PLZT particles in the molten salt undergoes a transition from a diffusion controlled mechanism to an interfacial reaction controlled mechanism at 900 deg. C

Symbiotic molten-salt systems coupled with accelerator molten-salt breeder (AMSB) or inertial-confined fusion hybrid molten-salt breeder (IHMSB) and their comparison

International Nuclear Information System (INIS)

Furukawa, K.

1984-01-01

Two types of breeder systems are proposed. One is the combined system of Accelerator Molten-Salt Breeder (AMSB) and Molten-Salt Converter Reactor (MSCR), and the other is the combined system of Inertial-confined Fusion Hybrid Molten-Salt Breeder (IHMSB) and modified MSCR. Both apply the molten-fluorides and have technically deep relations. AMSB would be much simpler and have already high technical feasibility. This will become economical the Th breeder system having a doubling time shorter than ten years and distributing any size of power stations MSCR. (orig.) [de

The electrodeposition and rare earths reduction in the molten salt actinides recovery systems using liquid metal

International Nuclear Information System (INIS)

Shim, J-B.; Lee, J-H.; Kwon, S-W.; Ahn, B-G.; Woo, M-S.; Lee, B-J.; Kim, E-H.; Park, H-S.; Yoo, J-H.

2005-01-01

A pyrochemical partitioning system uses liquid metals such as cadmium and bismuth in order to recover the actinide metals from a molten salt mixture containing rare earth fission product metals. The liquid metals play roles as a cathode in the electrowinning or an extracting phase in the reductive extraction operation. The product resulting from the above operations is metal-cadmium or-bismuth alloy, which should contain the rare earth element amounts as low as possible for a transmutation purpose. In this study, the electrodeposition behaviours of uranium and lanthanide elements such as La, Ce and Nd were investigated for solid molybdenum and liquid cadmium electrodes in a molten LiCl-KCl eutectic salt. Electrochemical methods used are a cyclic voltammetry (CV) and a chronopotentiometry for monitoring the salt phase and recovering the metals, respectively. The CV graphs for monitoring the oxidizing agent CdCl 2 in the salt phase were obtained. These show a time dependently disappearance of the oxidizing agent corresponding to the formation of UCl 3 by inserting the uranium metal into the salt. Also, a sequential oxidation technique which is added at a controlled amount of the oxidizing agents into the salt phase was applied. It was found that this method is feasible for the selective reduction of the rare earths content in liquid metal alloys. (author)

Separation of hafnium from zirconium in their tetrachloride solution in molten alkali metal chlorides

Energy Technology Data Exchange (ETDEWEB)

Salyulev, A B; Kudyakov, V Ya; Smirnov, M V; Moskalenko, N I [AN SSSR, Sverdlovsk. Inst. Ehlektrokhimii

1984-08-01

The coefficient of HfCl/sub 4/ and ZrCl/sub 4/ separation in the process of vapour sublimation from their solutions in molten NaCl, KCl, CsCl, NaCl-KCl and NaCl-CsCl equimolar mixtures is found to vary in the series from approximately 1.10 to approximately 1.22 and practically not to depend on the temperature (in the 600-910 deg) range and concentration (2-25 mol.% ZrCl/sub 4/+HfCl/sub 4/). HfCl/sub 4/ and ZrCl/sub 4/ are shown to form almost perfect solutions with each other, which in their turn form imperfect solutions with molten alkali metal chlorides, with the strength of hafnium complex chloride anions increasing higher than that of zirconium in the series from NaCl to CsCl.

Separation of hafnium from zirconium in their tetrachloride solution in molten alkali metal chlorides

International Nuclear Information System (INIS)

Salyulev, A.B.; Kudyakov, V.Ya.; Smirnov, M.V.; Moskalenko, N.I.

1984-01-01

The coefficient of HfCl 4 and ZrCl 4 separation in the process of vapour sublimation from their solutions in molten NaCl, KCl, CsCl, NaCl-KCl and NaCl-CsCl equimolar mixtures is found to vary in the series from approximately 1.10 to approximately 1.22 and practically not to depend on the temperature (in the 600-910 deg) range and concentration (2-25 mol.% ZrCl 4 +HfCl 4 ). HfCl 4 and ZrCl 4 are shown to form almost perfect solutions with each other, which in their turn form imperfect solutions with molten alkali metal chlorides, with the strength of hafnium complex chloride anions increasing higher than that of zirconium in the series from NaCl to CsCl

The applicability of activities in kinetic expressions: A more fundamental approach to represent the kinetics of the system CO2–OH-salt in terms of activities

NARCIS (Netherlands)

Haubrock, J.; Hogendoorn, Kees; Versteeg, Geert

2007-01-01

The applicability of utilizing activities instead of concentrations in kinetic expressions has been investigated using the reaction of CO2 in sodium hydroxide solutions also containing different neutral salts (LiCl, KCl and NaCl) as model system. For hydroxide systems it is known that when the

Thermodynamic properties of thulium and ytterbium in fused NaCl-KCl-CsCl eutectic

Energy Technology Data Exchange (ETDEWEB)

Novoselova, A., E-mail: A.Novoselova@ihte.uran.ru [Institute of High-Temperature Electrochemistry, Ural Division, Russian Academy of Science, S. Kovalevskaya Str., 22, Ekaterinburg 620990 (Russian Federation); Smolenski, V. [Institute of High-Temperature Electrochemistry, Ural Division, Russian Academy of Science, S. Kovalevskaya Str., 22, Ekaterinburg 620990 (Russian Federation)

2011-07-15

Research highlights: > Tm and Yb chloride compounds as fission products. > The investigation of electrochemical properties of lanthanides. > Determination of the apparent standard redox potentials of the couple Ln(III)/Ln(II) in fused NaCl-KCl-CsCl eutectic at (823 to 973) K. > The calculation of the basic thermodynamic properties of redox reaction in molten salt. - Abstract: This work presents the results of a study of the Tm{sup 3+}/Tm{sup 2+} and Yb{sup 3+}/Yb{sup 2+} couple redox potentials vs. Cl{sup -}/Cl{sub 2} reference electrode at the temperature range (823 to 973) K in fused NaCl-KCl-CsCl eutectic by direct potentiometric method. Initial concentrations of TmCl{sub 3} and YbCl{sub 3} in solvents did not exceed 5.0 mol%. Basic thermodynamic properties of the reactions TmCl{sub 2(l)} + 1/2 Cl{sub 2(g)} {r_reversible} TmCl{sub 3(l)} and YbCl{sub 2(l)} + 1/2 Cl{sub 2(g)} {r_reversible} YbCl{sub 3(l)} were calculated using the temperature dependencies of apparent standard potentials of the couples E{sub Tm{sup 3+}/Tm{sup 2+*}} and E{sub Yb{sup 3+}/Yb{sup 2+*}}.

Hot corrosion behaviour of austenitic steel-303 in molten chloride and carbonate salts

International Nuclear Information System (INIS)

Mohd Misbahul Amin; Shamsul Baharin Jamaludin; Che Mohd Ruzaidi Ghazali; Khairel Rafezi Ahmad

2007-01-01

The investigations are presented for the hot corrosion behaviors of Austenitic Steel-303, under influence of the molten chloride and carbonate salts viz KCl and K 2 CO 3 , oxidised at 1123 K for the period of 60 hour at atmospheric condition. The oxidation kinetic are effect of molten chloride and carbonate salts deposition on the oxidation rate were determined. The susceptibility to suffer a deleterious attack on the alloy by internal corrosion increases with increasing the time. In general, the corrosion resistance austenitic steel-303 in molten carbonate salts is much higher than chloride melt, being an active oxidizing agent providing oxygen during fluxing reaction. However, due to profuse evolution of CO/ CO 2 heavy mass losses are observed during corrosion and scales are porous. The test included mass change monitoring and surface layers were examined by means of scanning electron microscopy (SEM) studies. (author)

Electrorefining of High Carbon Ferromanganese in Molten Salts to Produce Pure Ferromanganese

Directory of Open Access Journals (Sweden)

Xiao S. J.

2017-09-01

Full Text Available High carbon ferromanganese is used as a starting material to prepare pure ferromanganese by electrorefining in molten salts. High carbon ferromanganese was applied as the anode, molybdenum was the cathode and Ag/AgCl was the reference electrode. The anodic dissolution was investigated by linear polarization in molten NaCl-KCl system. Then potentiostatic electrolysis was carried out to produce pure ferromanganese from high carbon ferromanganese. The cathodic product was determined to be a mixture of manganese and iron by x-ray diffraction (XRD. The content of carbon in the product was analyzed by carbon and sulfur analyzer. The post-electrolysis anode was characterized by scanning electron microscope (SEM. The mechanism of the anode dissolution and the distribution of the main impurity of carbon and silicon after electrolysis were discussed.

Interaction of phosphorus pentachloride with trichlorides of metals of the second half of lanthanide series and scandium subgroup

International Nuclear Information System (INIS)

Salyulev, A.B.; Vovkotrub, Eh.G.; Strekalovskij, V.N.

1999-01-01

With the use of Raman laser spectroscopy a study is made into interactions of molten TbCl 3 , ErCl 3 , YbCl 3 , YCl 3 and ScCl 3 with phosphorus pentachloride vapors at elevated pressure (up to 30-35 atm) as well as solid REM trichlorides with molten PCl 5 . It is revealed for first time that the interaction can be accompanied by reactions resulting in formation of complex chloride cations [PCl 4 ] + and anions [MCl 6 ] 3- of trivalent metals. The prediction is made about the possibility of chemical interaction of phosphorus pentachloride with trichlorides of all yttrium subgroup lanthanides under similar conditions

Study of structure and chemical interactions in molten salt mixtures on the base of tantalum fluorides

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Kirillov, S.A.; Prysyazhnyj, V.D.; AN Ukrainskoj SSR, Kiev. Inst. Obshchej i Neorganicheskoj Khimii)

1980-01-01

Using the method of IR-spectroscopy molten salt mixture containing K 2 TaF 7 , KF, KCl are investigated. It is detected that in the process of K 2 TaF 7 melting the TaF 6 - and TaF 7 2- ions are present in melt. When adding KF and KCl to the melt the equilibrium is shifted the direction of the TaF 7 2- and TaF 6 Cl 2- heptahaloid complexing respectively. In the melts with the composition close to the industrial electrolytes, containing K 2 TaF 7 , KF and KCl heptacoordinated tantalate ion is a prevailing one

Thermodynamics of HfCl/sub 4/-KCl molten mixtures containing HfCl/sub 4/ up to 33. 3 mol. per cent

Energy Technology Data Exchange (ETDEWEB)

Smirnov, M V; Salyulev, A B; Kudyakov, V Ya [AN SSSR, Sverdlovsk. Inst. Ehlektrokhimii

1980-05-01

Based on measurements of saturated vapour pressure in components of melted mixtures of HfCl/sub 4/-KCl, depending on temperature and concentration, calculated are the results of changes in activity coefficients of hafnium tetrachloride and potassium chloride on transition from diluted solutions, where the Henry law is met, to those concentrated where the law is disobeyed. Growth in the activity coefficient of HfCl/sub 4/ is due to dissociation of complex groups of HfCl/sub 6//sup 2 -/ into complexes with a lesser number of ligands and decreasing relative binding energy of Hf/sup 4 +/-Cl/sup -/ there. In this case, marked changes take place in partial enthalpy and entropy of hafnium tetrachloride mixing. Similar dependences are observed for potassium chloride, but they are expressed considerably weaker. Evaporation enthalpy and entropy are calculated for HfCl/sub 4/ and KCl monomers from their melted mixtures of various concentrations.

Studies on the Electrochemical Dissolution for the Treatment of 10 g-Scale Zircaloy-4 Cladding Hull Wastes in LiCl-KCl Molten Salts

International Nuclear Information System (INIS)

Lee, You Lee; Lee, Jang Hwa; Jeon, Min Ku; Kang, Kweon Ho

2012-01-01

The electrochemical behaviors of 10 g-scale fresh and oxidized Zircaloy-4 cladding hulls were examined in 500 degree C LiCl-KCl molten salts to confirm the feasibility of the electrorefining process for the treatment of hull wastes. In the results of measuring the potential-current response using a stainless steel basket filled with oxidized Zircaloy-4 hull specimens, the oxidation peak of Zr appears to be at -0.7 to -0.8 V vs. Ag/AgCl, which is similar to that of fresh Zircaloy-4 hulls, while the oxidation current is found to be much smaller than that of fresh Zircaloy-4 hulls. These results are congruent with the outcome of current-time curves at -0.78 V and of measuring the change in the average weight and thickness after the electrochemical dissolution process. Although the oxide layer on the surface affects the uniformity and rate of dissolution by decreasing the conductivity of Zircaloy-4 hulls, electrochemical dissolution is considered to occur owing to the defect of the surface and phase properties of the Zr oxide layer.

Use of alternative alkali chlorides in RT and PCR of polynucleotides containing G quadruplex structures.

Science.gov (United States)

Ramos-Alemán, Fabiola; González-Jasso, Eva; Pless, Reynaldo C

2018-02-15

Several alkali chlorides were compared for their use in reverse transcription (RT) and PCR of different types of nucleic acid templates. On a test region of biological DNA incapable of forming G quadruplex (G4) structures, Taq DNA polymerase showed similar PCR performance with 50 mM KCl, CsCl, LiCl, and NaCl. In contrast, on a synthetic model polydeoxyribonucleotide prone to G4 formation, good PCR amplification was obtained with 50 mM CsCl, but little or none with LiCl or KCl. Similarly, in RT of a G4-prone model polyribonucleotide, MMLV reverse transcriptase produced a good yield with 50 mM CsCl, mediocre yields with LiCl or without added alkali chloride, and a poor yield with 50 mM KCl. The full RT-PCR assay starting from the G4-prone polyribonucleotide, showed good results with CsCl in both stages, poor results with LiCl, and no product formation with KCl. The model polynucleotides showed fast G quadruplex formation under PCR or RT conditions with 50 mM KCl, but not with CsCl or LiCl. The results argue for the use of CsCl instead of KCl for RT and PCR of G4-prone sequences. No advantage was observed when using the 7-deaza type nucleotide analog c 7 dGTP in PCR amplification of the G4-prone polydeoxyribonucleotide. Copyright © 2017 Elsevier Inc. All rights reserved.

Lab-Scale Electrodeposition Behaviors of Pr(III) with Use of Quartz Cell in Molten LiCl-KCl Eutectic

Energy Technology Data Exchange (ETDEWEB)

Jee, Young Taek; Yun, Jong-Il [KAIST, Daejeon (Korea, Republic of)

2016-10-15

As electrorefining is proceeded, all actinides and lanthanides in metallic form are electrochemically oxidized and dissolved into the salt, while UCl{sub 3} in the salt is reduced and forms U-metal at solid cathodes. Since this unit process includes diverse actinides and recovers most of uranium, information on stream of nuclear materials and electrochemical condition inside of electrorefiner must continuously be notified not only for its performance assessment and process prediction but also for its safeguards. Currently, there are several computational models for electrorefiner (REFIN, ERAD, and etc.). However, the absence of model which reflects the change in surface area of cathode due to electrodeposition of UCl{sub 3} critically disturbs the precision of simulation. The change in surface area leads the change in current density, diffusion layer, potential and current gradient, and thus changes the entire electrochemical conditions in electrorefiner. In this paper, as a beginning step of investigating electrodeposition behavior of lanthanides and actinides, lab-scale electrodeposition experiments and methodological evaluation on the use of quartz cell are performed. In the lab-scale electrodeposition, sizes of quartz cell and deposited material became crucial factors for precise analysis of experiments. In a typical stabilized electrodeposition, CA diagram showed large plateau with reasonably increased magnitude of current due to the increase in surface area of working electrode. The amount of charge transferred (-61.55 C) can be utilized for concentration balance. According to ICP-OES, the decreased amount of bulk was 0.301 wt. % which was close to the expected decrease from the information of charge flow (0.29 wt. %). However, deposited material in contact with quartz wall in molten LiCl-KCl eutectic led a spontaneous reaction between each other. As an indicator of this undesired reaction, the cell became black, and enormous amount of charge was consumed. In

Electrochemical surface nitriding of pure iron by molten salt electrochemical process

Energy Technology Data Exchange (ETDEWEB)

Tsujimura, Hiroyuki; Goto, Takuya; Ito, Yasuhiko

2004-08-11

Electrochemical surface nitriding of pure iron was investigated in molten LiCl-KCl-Li{sub 3}N systems at 773 K. An outer compound layer and an inner diffusion layer were obtained by means of potentiostatic electrolysis at 1.00 V (versus Li{sup +}/Li). From XRD and SEM analyses, it was confirmed that the obtained compound layer consisted of {epsilon}-Fe{sub 2-3}N and {gamma}'-Fe{sub 4}N; the free energies of formation of the two nitrides are positive and the equilibrium nitrogen partial pressure of those are of the order of 10{sup 4} atm at 773 K. This result suggests that an apparent nitrogen partial pressure of at least the order of 10{sup 4} atm was imposed by the adsorbed nitrogen atoms (N{sub ads}) formed by anodic oxidation of nitride ion (N{sup 3-}) at the iron electrode surface.

Molten salt synthesis of ZnNb2O6 powder

International Nuclear Information System (INIS)

Guo Liangzhai; Dai Jinhui; Tian Jintao; Zhu Zhibin; He Tian

2007-01-01

Pure ZnNb 2 O 6 powder was successfully prepared by the molten salt synthesis method using Nb 2 O 5 and ZnO as raw materials and a mixture of NaCl and KCl as the solvent. The phase form and morphology of the prepared powder were characterized by X-ray diffraction and scanning electron microscopy. The effect of reacting temperature on phase formation was investigated. The results indicated that the single phase ZnNb 2 O 6 powder can be obtained by the molten salt synthesis method at 600 deg. C, and the SEM photographs show that the grains of the powder are rod-like particles

Combined system of accelerator molten-salt breeder (AMSB) apd molten-salt converter reactor (MSCR)

International Nuclear Information System (INIS)

Furukawa, K.; Kato, Y.; Ohmichi, T.; Ohno, H.

1983-01-01

A design and research program is discUssed of the development of accelerator molten-salt breeder (AMSB) consisting of a proton accelerator and a molten fluoride target. The target simultaneously serves as a blanket for fissionable material prodUction. An addition of some amoUnt of fissile nuclides to a melt expands the AMSB potentialities as the fissionable material production increases and the energy generation also grows up to the level of self-provision. Besides the blanket salts may be used as nuclear fuel for molten-salt converter reactor (MSCR). The combined AM SB+MSCR system has better parameters as compared to other breeder reactors, molten-salt breeder reactors (MSBR) included

Comparison of molten chloride and fluoride salts potentialities for An/Ln separation by electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Laplace, A.; Peron, F.; Marrot, F.; Lacquement, J. [DRCP/SCPS/LPP - CEA/CEN Valrho - BP 17171 - 30207 Bagnols/Ceze (France)

2008-07-01

The objective of this paper is the comparison of molten fluoride and chloride salts potentialities for Am/Nd separation by electrodeposition on inert cathode, on a purely thermodynamic point of view. The molten LiF-CaF{sub 2} eutectic (77-23 mol.%, at 780 deg. C) was considered for this study. Cyclic voltammetry showed a one step Am(III)/Am reduction at a potential of {approx_equal}+0.5 V vs. Li{sup +}/Li. A potential difference of 290 mV between Am and Nd metallic deposition was estimated by square-wave voltammetry. This Am/Nd potential difference is more important than in molten chlorides (220 mV in the LiCl-KCl eutectic at 500 deg. C). Moreover in molten fluoride salt, the americium and neodymium (+II) oxidation state is not stable contrary to the molten chloride one where corrosion of deposited Am would be potential. However this larger potential difference in molten fluorides is quite balanced by the higher working temperature. (authors)

Characteristics of YBa2Cu3O7 high-Tc superconductor with KCl

Science.gov (United States)

Yoon, Ki Hyun; Chang, Sung Sik

1990-03-01

The lattice parameters, microstructural change, transition temperature, and electrical properties of the YBa2-xKxCu3O7 high-Tc superconductor in the range from x=0 to x=0.25 have been investigated. The high-Tc orthorhombic phase increases with increasing KCl up to x=0.20, above which it decreases. The lattice parameters decrease with increasing KCl up to x=0.10, and then become nearly uniform. The grain size increases with increasing KCl up to x=0.20 due to its role as sintering agent. The specimens with x=0.2 have transition temperatures of 96 K and high magnetic susceptibility due to the contraction of lattice parameters a and b and the increase of orthorhombic distortion.

A novel molten-salt electrochemical cell for investigating the reduction of uranium dioxide to uranium metal by lithium using in situ synchrotron radiation.

Science.gov (United States)

Brown, Leon D; Abdulaziz, Rema; Jervis, Rhodri; Bharath, Vidal; Mason, Thomas J; Atwood, Robert C; Reinhard, Christina; Connor, Leigh D; Inman, Douglas; Brett, Daniel J L; Shearing, Paul R

2017-03-01

A novel electrochemical cell has been designed and built to allow for in situ energy-dispersive X-ray diffraction measurements to be made during reduction of UO 2 to U metal in LiCl-KCl at 500°C. The electrochemical cell contains a recessed well at the bottom of the cell into which the working electrode sits, reducing the beam path for the X-rays through the molten-salt and maximizing the signal-to-noise ratio from the sample. Lithium metal was electrodeposited onto the UO 2 working electrode by exposing the working electrode to more negative potentials than the Li deposition potential of the LiCl-KCl eutectic electrolyte. The Li metal acts as a reducing agent for the chemical reduction of UO 2 to U, which appears to proceed to completion. All phases were fitted using Le Bail refinement. The cell is expected to be widely applicable to many studies involving molten-salt systems.

Modification of thermal sensitivity of Chinese hamster cells by exposure to solutions of monovalent and divalent cationic salts

International Nuclear Information System (INIS)

Raaphorst, G.P.; Azzam, E.I.; Vadasz, J.

1984-06-01

Chinese hamster V79 cells were heated in culture medium or in 0.155-mol.dm -3 solutions of LiCl, NaCl, KCl, MgCl 2 , CaCl 2 and BaCl 2 . The presence of any one of these ionic solutions during heating increased the thermal sensitivity of the cells. The order of increased thermal sensitivity was KCl > LiCl > NaCl for the monovalent salts and BaCl 2 > MgCl 2 > CaCl 2 for the divalent cation salts. The addition of glucose to LiCl or NaCl solutions did not reduce the thermal sensitization caused by these solutions. When cells were sensitized by LiCl or NaCl treatment, a change in pH from 7.2 to 6.6 did not further increase thermal sensitivity. These data show that nutrient and ionic factors and their interplay are involved in cellular thermal sensitivity

Translational energy of products in the K+CH3COCl --> KCl+CH3CO reaction

Science.gov (United States)

Pauluth, M.; Rotzoll, G.

1984-08-01

Time-of-flight distributions of product KCl from the K+CH3COCl reaction have been measured over limited angular ranges at the collision energies 0.16 and 0.70 eV (cm). A simplified analysis assuming separability of cm angle and velocity yields the products' mean translational energy Ē'T. ĒT is very low for the lower collision energy, but increases with increasing collision energy. This finding is in accord with the photodissociation model of Herschbach, that predicts low repulsive energy release for this system.

Chemical properties of some elements in a molten lithium chloride, potassium chloride eutectic (1962)

International Nuclear Information System (INIS)

Molina, R.

1961-12-01

The increasing use of molten media especially in chemical preparations and for certain technological applications, has made it more necessary to have a knowledge of the chemical properties of elements in these solvents. Structural studies on molten solutions show the existence of certain species such as ions and complexes known to exist in aqueous solutions. This fact, together with certain experiments on chemical reactions in molten media has led us to establish a comparison between these media and aqueous solutions. We wish to show that the same fundamental phenomena occur in these media as are found in the chemistry of aqueous solutions and that this makes it possible to predict certain reactions. We have taken as examples the chemical properties of vanadium, uranium and sulphur in a LiCl-KCl eutectic melted at 480 deg. C. The first problem is to identify the various degrees of oxidation of these elements existing in the solvent chosen. We have tried to resolve it by comparing the absorption spectra obtained in aqueous solution and in the molten eutectic. We consider the possibilities of this method in a chapter on absorption spectrophotometry in the LiCl-KCl eutectic. During the study of the chemical properties we stress the various methods of displacing the equilibria: complex formation, variation of the oxidation-reduction properties with complex formation. The complexes of the O 2- ion are considered in particular. The study of the exchange of this particle is facilitated by the use of a classification of some of its complexes which we call the pO 2- scale by analogy with the pH scale; the value pO 2- is defined by the relationship: pO 2- = log O 2- Similarly, the use of apparent potential diagrams pO 2- makes it possible to predict and to interpret reactions involving the simultaneous exchange of electrons and O 2- ions between the various degrees of oxidation of the same element. It is possible, by studying some reactions of this type between two elements

Separation and Recovery of Uranium Metal from Spent Light Water Reactor Fuel via Electrolytic Reduction and Electrorefining

International Nuclear Information System (INIS)

Herrmann, S.D.; Li, S.X.

2010-01-01

A series of bench-scale experiments was performed in a hot cell at Idaho National Laboratory to demonstrate the separation and recovery of uranium metal from spent light water reactor (LWR) oxide fuel. The experiments involved crushing spent LWR fuel to particulate and separating it from its cladding. Oxide fuel particulate was then converted to metal in a series of six electrolytic reduction runs that were performed in succession with a single salt loading of molten LiCl - 1 wt% Li2O at 650 C. Analysis of salt samples following the series of electrolytic reduction runs identified the diffusion of select fission products from the spent fuel to the molten salt electrolyte. The extents of metal oxide conversion in the post-test fuel were also quantified, including a nominal 99.7% conversion of uranium oxide to metal. Uranium metal was then separated from the reduced LWR fuel in a series of six electrorefining runs that were performed in succession with a single salt loading of molten LiCl-KCl-UCl3 at 500 C. Analysis of salt samples following the series of electrorefining runs identified additional partitioning of fission products into the molten salt electrolyte. Analyses of the separated uranium metal were performed, and its decontamination factors were determined.

PDGF activates K-Cl cotransport through phosphoinositide 3-kinase and protein phosphatase-1 in primary cultures of vascular smooth muscle cells.

Science.gov (United States)

Zhang, Jing; Lauf, Peter K; Adragna, Norma C

2005-07-15

K-Cl cotransport (K-Cl COT, KCC) is an electroneutrally coupled movement of K and Cl present in most cells. In this work, we studied the pathways of regulation of K-Cl COT by platelet-derived growth factor (PDGF) in primary cultures of vascular smooth muscle cells (VSMCs). Wortmannin and LY 294002 blocked the PDGF-induced K-Cl COT activation, indicating that the phosphoinositide 3-kinase (PI 3-K) pathway is involved. However, PD 98059 had no effect on K-Cl COT activation by PDGF, suggesting that the mitogen-activated protein kinase pathway is not involved under the experimental conditions tested. Involvement of phosphatases was also examined. Sodium orthovanadate, cyclosporin A and okadaic acid had no effect on PDGF-stimulated K-Cl COT. Calyculin A blocked the PDGF-stimulated K-Cl COT by 60%, suggesting that protein phosphatase-1 (PP-1) is a mediator in the PDGF signaling pathway/s. In conclusion, our results indicate that the PDGF-mediated pathways of K-Cl COT regulation involve the signaling molecules PI 3-K and PP-1.

System design description of forced-convection molten-salt corrosion loops MSR-FCL-3 and MSR-FCL-4

International Nuclear Information System (INIS)

Huntley, W.R.; Silverman, M.D.

1976-11-01

Molten-salt corrosion loops MSR-FCL-3 and MSR-FCL-4 are high-temperature test facilities designed to evaluate corrosion and mass transfer of modified Hastelloy N alloys for future use in Molten-Salt Breeder Reactors. Salt is circulated by a centrifugal sump pump to evaluate material compatibility with LiF-BeF 2 -ThF 4 -UF 4 fuel salt at velocities up to 6 m/s (20 fps) and at salt temperatures from 566 to 705 0 C (1050 to 1300 0 F). The report presents the design description of the various components and systems that make up each corrosion facility, such as the salt pump, corrosion specimens, salt piping, main heaters, salt coolers, salt sampling equipment, and helium cover-gas system, etc. The electrical systems and instrumentation and controls are described, and operational procedures, system limitations, and maintenance philosophy are discussed

Electrochemical behaviour of ThF4 in LiCl-KCl eutectic

International Nuclear Information System (INIS)

Agarwal, Renu; Mukerjee, S.K.; Ramakumar, K.L.

2016-01-01

Pyrochemical processing of nuclear fuels is an integral part of molten salt reactor technology. Thorium containing molten salt reactors are relevant for transmutation of minor actinides and utilizations of vast thorium resources. Understanding chemical and electrochemical behavior of actinide and lanthanide ions in chloride melts is an important task in this process. A eutectic of lithium and potassium chloride is found to be the most suitable salt for this study due to its low melting, high reduction potential and significant solubility of most of the actinide and lanthanide salts. However, electrochemistry of thorium in chloride melt is inconsistent due to dispute over the presence of Th(II) cation along with Th(IV). In the present experiments, cyclic-voltammograms of ThF 4 in LiCl-KCl eutectic salt were measured using three electrodes cell, where all the electrodes were 1 mm molybdenum wires and counter electrode wire was twisted into a spiral shape to increase surface area and was used for mixing the salts in molten state. Cyclic-voltammograms of pure eutectic melt and with ThF 4 were measured at scanning rates 50-300 mV/s, at 648 K and 723 K. Diffusion coefficient of Th 4+ was calculated using Delahay equation

A basic study on capture and solidification of rare earth nuclide (Nd) in LiCl-KCl eutectic salt using an inorganic composite with Li{sub 2}OAl{sub 2}O{sub 3}- SiO{sub 2}-B{sub 2}O{sub 3} systems

Energy Technology Data Exchange (ETDEWEB)

Kim, Na Young; Eum, Hee Chul; Park, Hwan Seo; Ahn, Do Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2017-03-15

The pyroprocessing of spent nuclear fuel generates LiCl-KCl eutectic waste salt containing radioactive rare earth nuclides. It is necessary to develop a simple process for the treatment of LiCl-KCl eutectic waste in a hot-cell facility. In this study, capture and solidification of a rare earth nuclide (Nd) in LiCl-KCl eutectic salt using an inorganic composite with a Li{sub 2}OAl{sub 2}O{sub 3}- SiO{sub 2}-B{sub 2}O{sub 3} system was conducted to simplify the existing separation and solidification process of rare earth nuclides in LiCl-KCl eutectic waste salt from the pyroprocessing of spent nuclear fuel. More than 98wt% of Nd in LiCl-KCl eutectic salt was captured when the mass ratio of the composite was 0.67 over NdCl3 in the eutectic salt. The content of Nd{sub 2}O{sub 3} in the Nd captured-composite reached about 50wt%, and this composite was directly fabricated into a homogeneous and chemical resistant glass waste in a monolithic form. These results will be utilized in designing a process to simplify the existing separation and solidification process.

Molten-salt reactor information system

International Nuclear Information System (INIS)

Haubenreich, P.N.; Cardwell, D.W.; Engel, J.R.

1975-06-01

The Molten-Salt Reactor Information System (MSRIS) is a computer-based file of abstracts of documents dealing with the technology of molten-salt reactors. The file is stored in the IBM-360 system at ORNL, and may be searched through the use of established interactive computer programs from remote terminals connected to the computer via telephone lines. The system currently contains 373 entries and is subject to updating and expansion as additional information is developed. The nature and general content of the data file, a general approach for obtaining information from it, and the manner in which material is added to the file are described. Appendixes provide the list of keywords currently in use, the subject categories under which information is filed, and simplified procedures for searching the file from remote terminals. (U.S.)

Advances in molten salt electrochemistry towards future energy systems

International Nuclear Information System (INIS)

Ito, Yasuhiko

2005-01-01

This review article describes some selected novel molten salt electrochemical processes which have been created/developed by the author and his coworkers, with emphasis on the applications towards future energy systems. After showing a perspective of the applications of molten salt electrochemistry from the viewpoints of energy and environment, several selected topics are described in detail, which include nitride fuel cycle in a nuclear field, hydrogen energy system coupled with ammonia economy, thermally regenerative fuel cell systems, novel Si production process for solar cell and novel molten salt electrochemical processes for various energy and environment related functional materials including nitrides, rare earth-transition metal alloys, fine particles obtained by plasma-induced electrolysis, and carbon film. And finally, the author stresses again, the importance and potential of molten salt electrochemistry, and encourages young students, scientists and researchers to march in a procession hand in hand towards a bright future of molten salts. (author)

LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

Science.gov (United States)

Ko, Suk M.

1980-01-01

This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

Mock-up facilities for the development of an advanced spent fuel management process using molten salt technology

International Nuclear Information System (INIS)

Young-Joon Shin; Ik-Soo Kim; Seung-Chul Oh; Soo-Haeng Cho; Yo-Taik Song; Hyun-Soo Park

2000-01-01

The Korea Atomic Energy Research Institute (KAERI) has investigated a new approach to spent fuel storage technology that would reduce the total storage volume and the amount of decay heat. The technology utilizes the reduction of oxide fuel to a metal to reduce the volume and preferentially removing the fission products to reduce the decay heat. The uranium oxide is reduced to uranium metal by Li metal in a molten LiCl salt bath. During the reduction process, fission products are dissolved into the LiCl bath and some of the highly radioactive elements, such as Sr and Cs, are preferentially removed from the bath. The reduced uranium metal is cast into an ingot, put into a storage capsule, and stored using conventional storage methods. The fission products are treated as high level radioactive wastes. Each process of the technology has been studied and analyzed for technical feasibility, and has come to the point for designing and constructing of the mock-up for a demonstration of the technology. This paper presents the detailed design of the mock-up of the system and operational characteristics, along with all the details of the equipment for the system. KAERI plans to use the mock-up for the demonstration using an in-active spent fuel specimen. (authors)

Thermochemistry of alkali chloride - lanthanoide(III) chlorides

International Nuclear Information System (INIS)

Blachnik, R.; Selle, D.

1979-01-01

The phase diagrams of the mixtures KCl + GdCl 3 resp. DyCl 3 and of CsCl + PrCl 3 (DyCl 3 , ErCl 3 , and YbCl 3 ) were investigated by differential thermal analysis. In the mixtures of lanthanoide(III) chlorides with CsCl resp. KCl three different stoichiometries of the compounds were found, namely A 3 MCl 6 , A 2 MCl 5 , and AM 2 Cl 7 . Debyeograms of the compounds A 3 MCl 6 and AM 2 Cl 7 reveal, that in the case of the latter type all compounds with the same alkali halide have identical structure, whereas in the A 3 MCl 6 compounds three different types of X-ray patterns were observed. The stabilities of the congruently melting compounds can be estimated by comparing the melting point of the compound with the temperature of an extrapolated eutectic point. (author)

KCl stimulation increases norepinephrine transporter function in PC12 cells.

Science.gov (United States)

Mandela, Prashant; Ordway, Gregory A

2006-09-01

The norepinephrine transporter (NET) plays a pivotal role in terminating noradrenergic signaling and conserving norepinephrine (NE) through the process of re-uptake. Recent evidence suggests a close association between NE release and regulation of NET function. The present study evaluated the relationship between release and uptake, and the cellular mechanisms that govern these processes. KCl stimulation of PC12 cells robustly increased [3H]NE uptake via the NET and simultaneously increased [3H]NE release. KCl-stimulated increases in uptake and release were dependent on Ca2+. Treatment of cells with phorbol-12-myristate-13-acetate (PMA) or okadaic acid decreased [3H]NE uptake but did not block KCl-stimulated increases in [3H]NE uptake. In contrast, PMA increased [3H]NE release and augmented KCl-stimulated release, while okadaic acid had no effects on release. Inhibition of Ca2+-activated signaling cascades with KN93 (a Ca2+ calmodulin-dependent kinase inhibitor), or ML7 and ML9 (myosin light chain kinase inhibitors), reduced [3H]NE uptake and blocked KCl-stimulated increases in uptake. In contrast, KN93, ML7 and ML9 had no effect on KCl-stimulated [3H]NE release. KCl-stimulated increases in [3H]NE uptake were independent of transporter trafficking to the plasma membrane. While increases in both NE release and uptake mediated by KCl stimulation require Ca2+, different intracellular mechanisms mediate these two events.

Making a Pellet-type LiCl-KCl-UCl3 salt for Electrorefining

Energy Technology Data Exchange (ETDEWEB)

Woo, M. S.; Jin, H. J.; Kim, I. T.; Kim, J. G. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-05-15

The role of uranium chloride salt (UCl3) is to stabilize the initial cell voltage between electrodes in the electrorefining reactor. The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form the CdCl2 occurring in a Cd layer, followed by a process to produce UCl3 by the reaction of U in the LiCl-KCl eutectic salt and CdCl2 The apparatus for producing UCl3 consists of a chlorine gas generator, a uranium chlorinator, a Cd distiller, the pelletizer, and a off-gas and a dry scrubber. The temperature of the reactants is maintained at about 600 .deg. C. After the reaction is completed in the uranium chlorinator, The salt products is transferred to the Cd distiller to decrease residual Cd concentration in the salts, and then salt is transferred to the mould of pelletizer by a transfer system to make pellet type salt. Making pellet type LiCl-KCl-UCl3 salt for electrorefining was carried out using the chlorinator, Cd distiller, and pelletizer. Salt transfer carried out by salt transfer equipment heated 500 .deg. C. The Cd concentration of final salt products distillated at 60 torr, 2 hrs, 600 .deg. C was 200 ppm from the ICP, XRD analysis. And pellet type salt products were fabricated by using the mould of pelletizer at 90∼130 .deg. C.

Making a Pellet-type LiCl-KCl-UCl3 salt for Electrorefining

International Nuclear Information System (INIS)

Woo, M. S.; Jin, H. J.; Kim, I. T.; Kim, J. G.

2013-01-01

The role of uranium chloride salt (UCl3) is to stabilize the initial cell voltage between electrodes in the electrorefining reactor. The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form the CdCl2 occurring in a Cd layer, followed by a process to produce UCl3 by the reaction of U in the LiCl-KCl eutectic salt and CdCl2 The apparatus for producing UCl3 consists of a chlorine gas generator, a uranium chlorinator, a Cd distiller, the pelletizer, and a off-gas and a dry scrubber. The temperature of the reactants is maintained at about 600 .deg. C. After the reaction is completed in the uranium chlorinator, The salt products is transferred to the Cd distiller to decrease residual Cd concentration in the salts, and then salt is transferred to the mould of pelletizer by a transfer system to make pellet type salt. Making pellet type LiCl-KCl-UCl3 salt for electrorefining was carried out using the chlorinator, Cd distiller, and pelletizer. Salt transfer carried out by salt transfer equipment heated 500 .deg. C. The Cd concentration of final salt products distillated at 60 torr, 2 hrs, 600 .deg. C was 200 ppm from the ICP, XRD analysis. And pellet type salt products were fabricated by using the mould of pelletizer at 90∼130 .deg. C

Tritium loss in molten flibe systems

Energy Technology Data Exchange (ETDEWEB)

Longhurst, G.R.; Anderl, R.A. [Idaho National Eng. and Environ. Lab., Idaho Falls, ID (United States); Scott Willms, R. [Los Alamos National Lab., NM (United States)

2000-04-01

An emerging issue relative to beryllium technology in fusion involves tritium interactions with molten beryllium-bearing salts. Innovative designs for fusion reactors, both magnetic and inertially confined, feature the molten salt mixture 2LiF.BeF{sub 2}, commonly called Flibe, as a tritium breeder and coolant. Tritium is bred in the Flibe as neutrons from the plasma are absorbed by Li atoms, which then transmute to tritium and helium. Transmutation of tritium from Be also occurs. Among the issues to be resolved for such coolant systems is the potential loss of tritium from the Flibe coolant to the walls of the system, particularly through heat exchanger tubes, and from there into secondary coolants or working fluids and the environment. Effectively removing tritium from Flibe in clean-up units is also important. In quiescent or low Reynolds number flow, tritium movement through Flibe is governed by diffusion. For Flibe in turbulent flow, as in heat exchanger tubes, transport is by turbulent mixing, and the same flow conditions and structural design features that maximize heat transfer to the heat exchanger walls will enhance the transport of tritium to those same surfaces. Analyses have been performed to estimate the fractional loss of tritium through heat exchanger tubes and release rates from Flibe droplets in vacuum disengagers in molten Flibe systems. The calculations suggest unacceptably large losses of tritium through heat exchanger tubes. The gravity of the implications of these estimates calls for experimental verification to determine if tritium losses through molten Flibe heat exchangers or other Flibe systems can really be so high and whether vacuum disengagers will really work. There is also a need for better information on evolution of tritium from Flibe droplets in a vacuum. Several experiments are presently being planned to address these issues and are discussed. These include experiments to induce tritium in Flibe using spontaneous fission neutrons

Tritium loss in molten flibe systems

International Nuclear Information System (INIS)

Longhurst, G.R.; Anderl, R.A.; Scott Willms, R.

2000-01-01

An emerging issue relative to beryllium technology in fusion involves tritium interactions with molten beryllium-bearing salts. Innovative designs for fusion reactors, both magnetic and inertially confined, feature the molten salt mixture 2LiF.BeF 2 , commonly called Flibe, as a tritium breeder and coolant. Tritium is bred in the Flibe as neutrons from the plasma are absorbed by Li atoms, which then transmute to tritium and helium. Transmutation of tritium from Be also occurs. Among the issues to be resolved for such coolant systems is the potential loss of tritium from the Flibe coolant to the walls of the system, particularly through heat exchanger tubes, and from there into secondary coolants or working fluids and the environment. Effectively removing tritium from Flibe in clean-up units is also important. In quiescent or low Reynolds number flow, tritium movement through Flibe is governed by diffusion. For Flibe in turbulent flow, as in heat exchanger tubes, transport is by turbulent mixing, and the same flow conditions and structural design features that maximize heat transfer to the heat exchanger walls will enhance the transport of tritium to those same surfaces. Analyses have been performed to estimate the fractional loss of tritium through heat exchanger tubes and release rates from Flibe droplets in vacuum disengagers in molten Flibe systems. The calculations suggest unacceptably large losses of tritium through heat exchanger tubes. The gravity of the implications of these estimates calls for experimental verification to determine if tritium losses through molten Flibe heat exchangers or other Flibe systems can really be so high and whether vacuum disengagers will really work. There is also a need for better information on evolution of tritium from Flibe droplets in a vacuum. Several experiments are presently being planned to address these issues and are discussed. These include experiments to induce tritium in Flibe using spontaneous fission neutrons

Novel waste printed circuit board recycling process with molten salt.

Science.gov (United States)

Riedewald, Frank; Sousa-Gallagher, Maria

2015-01-01

The objective of the method was to prove the concept of a novel waste PCBs recycling process which uses inert, stable molten salts as the direct heat transfer fluid and, simultaneously, uses this molten salt to separate the metal products in either liquid (solder, zinc, tin, lead, etc.) or solid (copper, gold, steel, palladium, etc.) form at the operating temperatures of 450-470 °C. The PCB recovery reactor is essentially a U-shaped reactor with the molten salt providing a continuous fluid, allowing molten salt access from different depths for metal recovery. A laboratory scale batch reactor was constructed using 316L as suitable construction material. For safety reasons, the inert, stable LiCl-KCl molten salts were used as direct heat transfer fluid. Recovered materials were washed with hot water to remove residual salt before metal recovery assessment. The impact of this work was to show metal separation using molten salts in one single unit, by using this novel reactor methodology. •The reactor is a U-shaped reactor filled with a continuous liquid with a sloped bottom representing a novel reactor concept.•This method uses large PCB pieces instead of shredded PCBs as the reactor volume is 2.2 L.•The treated PCBs can be removed via leg B while the process is on-going.

Novel waste printed circuit board recycling process with molten salt

Science.gov (United States)

Riedewald, Frank; Sousa-Gallagher, Maria

2015-01-01

The objective of the method was to prove the concept of a novel waste PCBs recycling process which uses inert, stable molten salts as the direct heat transfer fluid and, simultaneously, uses this molten salt to separate the metal products in either liquid (solder, zinc, tin, lead, etc.) or solid (copper, gold, steel, palladium, etc.) form at the operating temperatures of 450–470 °C. The PCB recovery reactor is essentially a U-shaped reactor with the molten salt providing a continuous fluid, allowing molten salt access from different depths for metal recovery. A laboratory scale batch reactor was constructed using 316L as suitable construction material. For safety reasons, the inert, stable LiCl–KCl molten salts were used as direct heat transfer fluid. Recovered materials were washed with hot water to remove residual salt before metal recovery assessment. The impact of this work was to show metal separation using molten salts in one single unit, by using this novel reactor methodology. • The reactor is a U-shaped reactor filled with a continuous liquid with a sloped bottom representing a novel reactor concept. • This method uses large PCB pieces instead of shredded PCBs as the reactor volume is 2.2 L. • The treated PCBs can be removed via leg B while the process is on-going. PMID:26150977

New rational nuclear energy system composed of accelerator molten-salt breeder (AMSB) and molten-salt power stations (MSCR)

International Nuclear Information System (INIS)

Furukawa, K.

1985-01-01

For the next century, it was predicted that some rational fission energy system breeding in significantly short doubling time less than 10 years should be developed replacing the fossil fuels. In practice, this rationality, that is, simplicity and high economy could be realized by the natural combination of: molten salt fuel concept; accelerator (spallation) breeding concept; and Thorium fuel cycle concept, in the symbiont system of Accelerator Molten-Salt breeders and Molten-Salt Power Stations. The economy of this system might significantly become better than the other breeder systems, although the prediction in Chapter 6 was too much conservative. Its more important aspect is the low cost of future R and D, which depend on the rational character of Molten-Fluoride Technology and really is verified by the basic R and D cost (only $0.13 B) in Oak Ridge N.L. It is interesting that molten-salt technology will be able to apply to chemical processing of U-Pu oxide fuels by the developing effort by USSR in near future. This fact and the demand of small power stations such as 150MWe MSCR presented here will be able to bridge between the present and the next century

Diffusion phenomena of fluorine and cations in molten Li2BeF4, LiBeF3 and NaBeF3

International Nuclear Information System (INIS)

Ohno, Hideo

1984-03-01

Self-diffusion coefficients of fluorine and cations in molten LiF-BeF 2 and NaF-BeF 2 systems were summarized by the capillary reservoir technique. The diffusion coefficients and the activation energies of cations in these molten salts follow a similar behavior with those of cations in molten alkali halides. On the other hand, self-diffusion of fluorine have unusually high diffusion coefficients and activation energies. The characteristic diffusion phenomena of fluorine in these molten alkali fluoroberyllates are very similar to those of oxygen in molten CaO-SiO 2 and CaO-SiO 2 -Al 2 O 3 slag. The dynamical behavior of Li and F in molten Li 2 BeF 4 was also analyzed by NMR technique. According to both these experiments, most probable mechanism of characteristic diffusion of fluorine in these molten systems could be dissociation of F atom from complex anion and long distance diffusion. (author)

Mass transfer performance comparison of two commonly used liquid desiccants: LiBr and LiCl aqueous solutions

International Nuclear Information System (INIS)

Liu, X.H.; Yi, X.Q.; Jiang, Y.

2011-01-01

Mass transfer performance of two commonly used liquid desiccants, LiBr aqueous solution and LiCl aqueous solution, is compared in this paper on the basis of the same solution temperature and surface vapor pressure. According to the analysis of the analytical solutions of heat and mass transfer processes, the key performance influencing factors are heat capacity ratio of air to desiccant m * and mass transfer unit NTU m . The heat capacities of the two liquid desiccants are about the same at same volumetric flow rate, and LiBr solution has higher density and smaller specific heat capacity. The variance of mass transfer unit with different operating conditions and liquid desiccants are derived based on the experimental results. In the condition of the same desiccant mass flow rate, the dehumidification performance of LiCl solution is better, and the regeneration performance of LiBr solution is a little better or almost the same as that of LiCl solution. In the condition of the same desiccant volumetric flow rate, the dehumidification performance of LiCl solution is a little better or about the same compared with LiBr solution, and the regeneration performance of LiBr solution is better. The COPs of the liquid desiccant systems using these two desiccants are similar; while LiCl solution costs 18% lower than LiBr solution at current Chinese price.

Determination of the extent of reduction of dense UO{sub 2} cathodes from direct electrochemical reduction studies in molten chloride medium

Energy Technology Data Exchange (ETDEWEB)

Sri Maha Vishnu, D.; Sanil, N. [Fuel Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Murugesan, N. [Materials Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Shakila, L. [Fuel Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Ramesh, C. [Materials Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Mohandas, K.S., E-mail: ksmd@igcar.gov.in [Fuel Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Nagarajan, K. [Fuel Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

2012-08-15

Electro-reduction of solid UO{sub 2} to U has been studied with molten CaCl{sub 2} or LiCl as the electrolyte medium. Electro-reduction of thick (>3 mm), powder compacted and sintered pellets of UO{sub 2} showed incomplete reduction resulting in a mixture of uranium metal and UO{sub 2}. The extent of reduction of UO{sub 2} to U was determined by employing a novel method called 'metal estimation by hydrogen sensor (MEHS)', in which the hydrogen evolved during the reaction of U metal in the reduced product with con. HBr was measured using an in-house developed polymer electrolyte based amperometric hydrogen sensor. The results of our investigations on incompletely reduced UO{sub 2} pellets in both CaCl{sub 2} and LiCl melts showed that the extent of reduction of different regions of the oxide pellet was different. It varied from 88.3% on the surface of the pellet as against 3.7% towards the centre bulk during electro-reduction in CaCl{sub 2} (at 1173 K). The metallisation was found restricted to the surface of the pellets reduced in LiCl melt (at 923 K). Electro-reduction of small chunks of UO{sub 2} pellet in CaCl{sub 2} melt resulted in products with lower extent of reduction. Based on the measurements, a probable mechanism on the propagation of reduction through the solid UO{sub 2} matrix during the electrochemical reduction process has been proposed.

Preparation of uranium coatings by electro deposition in molten chloride media

International Nuclear Information System (INIS)

Taxil, P.; Serrano, K.; Dugne, O.

2001-01-01

The electrodeposition of uranium is now a relevant topic for two kinds of applications: the preparation of this metal with compounds extracted from the mineral ores; the separation from lanthanides in the nuclear waste. This paper concerns the process of preparation of uranium metal on various substrates, using the electro deposition process in molten salts. The electrolyte consists of an eutectic mixture NaCl-KCl as solvent (fusion point 650 deg C) and a tetravalent uranium compound, UCl 4 as solute. We present the results, theoretical and practical, necessary to manage the process. So, the following points will be considered stepwise in this paper: the electrochemical behaviour of uranium III ions in the electrolyte, since it is now clearly established that uranium metal can be prepared by electrochemical reduction of UCl 3 in a NaCl-KCl mixture in a single step process: U III + 3 e → U 0 ; the crystallisation mode of uranium on the cathodic material; the preparation of uranium coatings with variables conditions: temperature, electrolyte concentration, current density and cathodic substrate; the observation of the crystal growth on the substrates, by using SEM micrographies. (authors)

Integrated Data Collection Analysis (IDCA) Program - KClO₃/Dodecane Mixture

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-05-23

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO₃ and dodecane—KClO₃/dodecane mixture. This material was selected because of the challenge of performing SSST testing of a mixture of solid and liquid materials. The mixture was found to: 1) be more sensitive to impact than RDX, and PETN, 2) less sensitive to friction than PETN, and 3) less sensitive to spark than RDX. The thermal analysis showed little or no exothermic features suggesting that the dodecane volatilized at low temperatures. A prominent endothermic feature was observed assigned to melting of KClO₃. This effort, funded by the Department of Homeland Security (DHS), ultimately will put the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study has the potential to suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. Note, however, the test procedures differ among the laboratories. The results are compared among the laboratories and then compared to historical data from various sources. The testing performers involved for the KClO₃/dodecane mixture are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Indian Head Division, Naval Surface Warfare Center, (NSWC IHD). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to understand

Electrochemical extraction of neodymium by co-reduction with aluminum in LiCl–KCl molten salt

International Nuclear Information System (INIS)

Yan, Yong-De; Xu, Yan-Lu; Zhang, Mi-Lin; Xue, Yun; Han, Wei; Huang, Ying; Chen, Qiong; Zhang, Zhi-Jian

2013-01-01

The electrochemical behavior of Nd(III) ions in LiCl–KCl and LiCl–KCl–AlCl 3 melts on a Mo electrode at 723 K was studied by various electrochemical techniques. The results showed that Nd(III) ions are reduced to Nd(0) through two consecutive steps, and the underpotential deposition of neodymium on pre-deposited Al electrode formed two kinds of Al–Nd intermetallic compounds in LiCl–KCl–AlCl 3 solutions. The electrochemical extraction of neodymium was carried out in LiCl–KCl–AlCl 3 melts on a Mo electrode at 873 K by potentiostatic and galvanostatic electrolysis. The extraction efficiency was 99.25% after potentiostatic electrolysis for 30 h. Al–Li–Nd bulk alloy was obtained by galvanostatic electrolysis. X-ray diffraction (XRD) suggested that Al 2 Nd and Al 3 Nd phases were formed in Al–Li–Nd alloy. The microstructure and micro-zone chemical analysis of Al–Li–Nd alloy were characterized by scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS), respectively

High density liquid structure enhancement in glass forming aqueous solution of LiCl

Science.gov (United States)

Camisasca, G.; De Marzio, M.; Rovere, M.; Gallo, P.

2018-06-01

We investigate using molecular dynamics simulations the dynamical and structural properties of LiCl:6H2O aqueous solution upon supercooling. This ionic solution is a glass forming liquid of relevant interest in connection with the study of the anomalies of supercooled water. The LiCl:6H2O solution is easily supercooled and the liquid state can be maintained over a large decreasing temperature range. We performed simulations from ambient to 200 K in order to investigate how the presence of the salt modifies the behavior of supercooled water. The study of the relaxation time of the self-density correlation function shows that the system follows the prediction of the mode coupling theory and behaves like a fragile liquid in all the range explored. The analysis of the changes in the water structure induced by the salt shows that while the salt preserves the water hydrogen bonds in the system, it strongly affects the tetrahedral hydrogen bond network. Following the interpretation of the anomalies of water in terms of a two-state model, the modifications of the oxygen radial distribution function and the angular distribution function of the hydrogen bonds in water indicate that LiCl has the role of enhancing the high density liquid component of water with respect to the low density component. This is in agreement with recent experiments on aqueous ionic solutions.

Development of pyrometallurgical partitioning technology of long-lived nuclides. Recovery of volatile chlorides for chlorination process using molten salt trap. 1

International Nuclear Information System (INIS)

Hijikata, Takatoshi; Nakamura, Kyosei; Kurata, Masateru; Konagaya, Hideaki

1997-01-01

The dry process for partitioning of long-lived nuclides from high level radioactive waste has been developed. One of the subjects for development of this process is the recovering of the volatilization of chlorides for the chlorination process. We proposed that the volatile chlorides were recovered by the molten salt trap. We researched the behavior of volatile chlorides (ferric chloride, zirconium tetra-chloride and molybdenum pent-chloride) in LiCl-KCl eutectic salt. In this result, the volatile rate of these chlorides was slower than the volatile rate of undissolved chlorides in LiCl-KCl eutectic salt. Also, we make a prototype of molten salt trap for recovering the volatile chlorides and tested the performance of this experimental apparatus and recovering ratio of volatile chlorides. This trap has a good performance of recovering volatile chlorides. (author)

Hot corrosion behavior of plasma-sprayed partially stabilized zirconia coatings in a lithium molten salt

International Nuclear Information System (INIS)

Cho, Soo Haeng; Hong, Sun Seok; Kang, Dae Seong; Park, Byung Heong; Hur, Jin Mok; Lee, Han Soo

2008-01-01

The electrolytic reduction of spent oxide fuel involves the liberation of oxygen in a molten LiCl electrolyte, which results in a chemically aggressive environment that is too corrosive for typical structural materials. It is essential to choose the optimum material for the process equipment handling molten salt. IN713LC is one of the candidate materials proposed for application in electrolytic reduction process. In this study, Yttria-Stabilized Zirconia (YSZ) top coat was applied to a surface of IN713LC with an aluminized metallic bond coat by an optimized plasma spray process, and were investigated the corrosion behavior at 675 .deg. C for 216 hours in the molten salt LiCl-Li 2 O under an oxidizing atmosphere. The as-coated and tested specimens were examined by OM, SEM/EDS and XRD, respectively. The bare superalloy reveals obvious weight loss, and the corrosion layer formed on the surface of the bare superalloy was spalled due to the rapid scale growth and thermal stress. The top coatings showed a much better hot-corrosion resistance in the presence of LiCl-Li 2 O molten salt when compared to those of the uncoated superalloy and the aluminized bond coatings. These coatings have been found to be beneficial for increasing to the hot-corrosion resistance of the structural materials for handling high temperature lithium molten salts

Performance of the mesh-type liquid cadmium cathode structure for the electrodeposition of uranium from the molten salt

International Nuclear Information System (INIS)

Paek, S.; Kim, S.H.; Lee, H.; Ahn, D.H.; Yoon, D.S.

2010-01-01

A mesh-type liquid cadmium cathode (LCC) structure has been devised to improve the performance of the electro-winning process for the recovery of actinides in a molten chloride system. For the verification of its performance, electrodeposition experiments of uranium from the molten LiCl-KCl-UCl 3 salt were conducted at 773 K for different current densities using the mesh-type LCC structure. Uranium was successfully collected over 5 wt. % in the LCC without growing uranium dendrites. The mesh-type LCC structure prevented the uncontrolled growth of uranium dendrites into the electrolyte phase above the cadmium surface and caused the LCC deposit to accumulate at the higher in the cadmium phase over uranium solubility in cadmium. After cooling the LCC crucible, its solid deposits were identified as an intermetallic compound UCd 11 by EPMA and XRD analysis. The cathode potential profiles from the electrochemical experiments and the chemical structure of the LCC deposits showed that it could be applied practically to recover the actinides above their solubility in cadmium. (orig.)

Heterogeneity of equilibrium molten globule state of cytochrome c induced by weak salt denaturants under physiological condition.

Directory of Open Access Journals (Sweden)

Hamidur Rahaman

Full Text Available While many proteins are recognized to undergo folding via intermediate(s, the heterogeneity of equilibrium folding intermediate(s along the folding pathway is less understood. In our present study, FTIR spectroscopy, far- and near-UV circular dichroism (CD, ANS and tryptophan fluorescence, near IR absorbance spectroscopy and dynamic light scattering (DLS were used to study the structural and thermodynamic characteristics of the native (N, denatured (D and intermediate state (X of goat cytochorme c (cyt-c induced by weak salt denaturants (LiBr, LiCl and LiClO4 at pH 6.0 and 25°C. The LiBr-induced denaturation of cyt-c measured by Soret absorption (Δε400 and CD ([θ]409, is a three-step process, N ↔ X ↔ D. It is observed that the X state obtained along the denaturation pathway of cyt-c possesses common structural and thermodynamic characteristics of the molten globule (MG state. The MG state of cyt-c induced by LiBr is compared for its structural and thermodynamic parameters with those found in other solvent conditions such as LiCl, LiClO4 and acidic pH. Our observations suggest: (1 that the LiBr-induced MG state of cyt-c retains the native Met80-Fe(III axial bond and Trp59-propionate interactions; (2 that LiBr-induced MG state of cyt-c is more compact retaining the hydrophobic interactions in comparison to the MG states induced by LiCl, LiClO4 and 0.5 M NaCl at pH 2.0; and (3 that there exists heterogeneity of equilibrium intermediates along the unfolding pathway of cyt-c as highly ordered (X1, classical (X2 and disordered (X3, i.e., D ↔ X3 ↔ X2 ↔ X1 ↔ N.

Electrokinetic properties of tantalum oxide deposited on model substrate in NaCl and LiCl solutions

International Nuclear Information System (INIS)

Sidorova, M.P.; Bogdanova, N.F.; Ermakova, L.Eh.; Bobrov, P.V.

1997-01-01

Electrokinetic characteristics of tantalum oxide have been studied using a model system - a plane-parallel capillary in chloride solutions containing monocharge (H + , Na + , Li + ) counterions in a wide range of pH and concentrations. It is shown that position of isoelectric point (IEP) of Ta 2 O 5 depends on concentration and type of counterion, moreover, the dependence is not explained in the framework of classical notions of the influence of counterion specific adsorption on IEP position. Electrokinetic potential of Ta 2 O-5 surface at the background of diluted LiCl solutions is higher in its absolute value, than at the background of NaCl solutions according to direct lyotropic series. The results of measurements of the capillary resistance dependence on pH at the background of NaCl and LiCl solutions 10 -3 -10 -1 M are used for the calculation of efficiency and specific surface conductivity factors

Elaboration and characterization of a KCl single crystal doped with nanocrystals of a Sb2O3 semiconductor

International Nuclear Information System (INIS)

Bouhdjer, L.; Addala, S.; Halimi, O.; Boudine, B.; Sebais, M.; Chala, A.

2013-01-01

Undoped and doped KCl single crystals have been successfully elaborated via the Czochralski (Cz) method. The effects of dopant Sb 2 O 3 nanocrystals on structural and optical properties were investigated by a number of techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDAX) analysis, UV-visible and photoluminescence (PL) spectrophotometers. An XRD pattern of KCl:Sb 2 O 3 reveals that the Sb 2 O 3 nanocrystals are in the well-crystalline orthorhombic phase. The broadening of diffraction peaks indicated the presence of a Sb 2 O 3 semiconductor in the nanometer size regime. The shift of absorption and PL peaks is observed near 334 nm and 360 nm respectively due to the quantum confinement effect in Sb 2 O 3 nanocrystals. Particle sizes calculated from XRD studies agree fairly well with those estimated from optical studies. An SEM image of the surface KCl:Sb 2 O 3 single crystal shows large quasi-spherical of Sb 2 O 3 crystallites scattered on the surface. The elemental analysis from EDAX demonstrates that the KCl:Sb 2 O 3 single crystal is slightly rich in oxygen and a source of excessive quantities of oxygen is discussed. (semiconductor materials)

KCl cotransport regulation and protein kinase G in cultured vascular smooth muscle cells.

Science.gov (United States)

Adragna, N C; Zhang, J; Di Fulvio, M; Lincoln, T M; Lauf, P K

2002-05-15

K-Cl cotransport is activated by vasodilators in erythrocytes and vascular smooth muscle cells and its regulation involves putative kinase/phosphatase cascades. N-ethylmaleimide (NEM) activates the system presumably by inhibiting a protein kinase. Nitrovasodilators relax smooth muscle via cGMP-dependent activation of protein kinase G (PKG), a regulator of membrane channels and transporters. We investigated whether PKG regulates K-Cl cotransport activity or mRNA expression in normal, PKG-deficient-vector-only-transfected (PKG-) and PKG-catalytic-domain-transfected (PKG+) rat aortic smooth muscle cells. K-Cl cotransport was calculated as the Cl-dependent Rb influx, and mRNA was determined by semiquantitative RT-PCR. Baseline K-Cl cotransport was higher in PKG+ than in PKG- cells (p <0.01). At 0.5 mM, NEM stimulated K-Cl cotransport by 5-fold in PKG- but not in PKG+ cells. However, NEM was more potent although less effective to activate K-Cl cotransport in normal (passage 1-3) and PKG+ than in PKG- cells. In PKG- cells, [(dihydroindenyl) oxy] alkanoic acid (300 mM) but not furosemide (1 mM) inhibited K-Cl cotransport. Furthermore, no difference in K-Cl cotransport mRNA expression was observed between these cells. In conclusion, this study shows that manipulation of PKG expression in vascular smooth muscle cells affects K-Cl cotransport activity and its activation by NEM.

Pyrochemical extraction for selective removal of transuranium elements from molten LiCl-KCl

International Nuclear Information System (INIS)

Ackermann, J.P.; Johnson, T.R.

1993-01-01

Recent determinations of separation factors that describe partition of the actinide and rare earth elements between liquid cadmium and LiCl-KCl eutectic allowed identification of a process for selective removal of the transuranium (TRU) element chlorides from the electrolyte used for electrofining of metal fuel from the Integral Fast Reactor. It is periodically necessary to remove rare earth elements from the electrolyte to limit heat generation from radioactive decay. Countercurrent extraction of electrolyte with uranium in cadmium solution allows retention of valuable TRU elements in the reprocessed fuel, and results in a rare earth waste stream that is essentially free of TRU elements and their concomitant long-term hazards

Electro-separation of actinides using Al cathodes in LiCl-KCl

Energy Technology Data Exchange (ETDEWEB)

Serp, J.; Malmbeck, R.; Scheppler, C.; Glatz, J.P

2004-07-01

In this work, the reprocessing of a simulated spent fuel (U{sub 60}Pu{sub 20}Zr{sub 10}Am{sub 2}Nd{sub 3.5}Y{sub 0.5}Ce{sub 0.5}Gd{sub 0.5}) have been studied by electrolysis in molten chloride salt on a solid Al cathode. The electrorefining was carried out under constant current at 733 Kin LiCl-KCl eutectic. In one electrolysis of 1386 C, a total of 1.13 g of actinides were recovered as alloy on the Al cathode. The obtained deposit was dissolved in HNO{sub 3} (7 M) and analysed by ICP-MS. The deposit was found to be composed mainly of U (90.3 %), Pu (9.3 %) and Am (0.3 %). The mass balance indicated a faradic yield close to 100%. The U/Nd, Pu/Nd and Am/Nd ratios in the deposit were 2800, 290 and 10, respectively. Therefore excellent separation of U and Pu was obtained and a separation of MA from Ln seems to be possible even with a low initial Am/Nd concentration ratio (0.41) in the salt phase. (authors)

Phase relations in the system NaCl-KCl-H2O: IV. Differential thermal analysis of the sylvite liquidus in the KCl-H2O binary, the liquidus in the NaCl-KCl-H2O ternary, and the solidus in the NaCl-KCl binary to 2 kb pressure, and a summary of experimental data for thermodynamic-PTX analysis of solid-liquid equilibria at elevated P-T conditions

Science.gov (United States)

Chou, I.-Ming; Sterner, S.M.; Pitzer, Kenneth S.

1992-01-01

The sylvite liquidus in the binary system KCl-H2O and the liquidus in the ternary system NaCl-KCl-H2O were determined by using isobaric differential thermal analysis (DTA) cooling scans at pressures up to 2 kbars. Sylvite solubilities along the three-phase curve in the binary system KCl-H2O were obtained by the intersection of sylvite-liquidus isopleths with the three-phase curve in a P-T plot. These solubility data can be represented by the equation Wt.% KCl (??0.2) = 12.19 + 0.1557T - 5.4071 ?? 10-5 T2, where 400 ??? T ??? 770??C. These data are consistent with previous experimental observations. The solidus in the binary system NaCl-KCl was determined by using isobaric DTA heating scans at pressures up to 2 kbars. Using these liquidus and solidus data and other published information, a thermodynamic-PTX analysis of solid-liquid equilibria at high pressures and temperatures for the ternary system has been performed and is presented in an accompanying paper (Part V of this series). However, all experimental liquidus, solidus, and solvus data used in this analysis are summarized in this report (Part IV) and they are compared with the calculated values based on the analysis. ?? 1992.

Pressure induced structural phase transition in solid oxidizer KClO3: A first-principles study

Science.gov (United States)

Yedukondalu, N.; Ghule, Vikas D.; Vaitheeswaran, G.

2013-05-01

High pressure behavior of potassium chlorate (KClO3) has been investigated from 0 to 10 GPa by means of first principles density functional theory calculations. The calculated ground state parameters, transition pressure, and phonon frequencies using semiempirical dispersion correction scheme are in excellent agreement with experiment. It is found that KClO3 undergoes a pressure induced first order phase transition with an associated volume collapse of 6.4% from monoclinic (P21/m) → rhombohedral (R3m) structure at 2.26 GPa, which is in good accord with experimental observation. However, the transition pressure was found to underestimate (0.11 GPa) and overestimate (3.57 GPa) using local density approximation and generalized gradient approximation functionals, respectively. Mechanical stability of both the phases is explained from the calculated single crystal elastic constants. In addition, the zone center phonon frequencies have been calculated using density functional perturbation theory at ambient as well as at high pressure and the lattice modes are found to soften under pressure between 0.6 and 1.2 GPa. The present study reveals that the observed structural phase transition leads to changes in the decomposition mechanism of KClO3 which corroborates with the experimental results.

Physical properties of core-concrete systems: Al{sub 2}O{sub 3}-ZrO{sub 2} molten materials measured by aerodynamic levitation

Energy Technology Data Exchange (ETDEWEB)

Ohishi, Yuji, E-mail: ohishi@see.eng.osaka-u.ac.jp [Graduate School of Engineering, Osaka University (Japan); Kargl, F. [Institute of Materials Physics in Space, German Aerospace Center (Germany); Nakamori, F.; Muta, Hiroaki; Kurosaki, Ken [Graduate School of Engineering, Osaka University (Japan); Yamanaka, Shinsuke [Graduate School of Engineering, Osaka University (Japan); Research Institute of Nuclear Engineering, University of Fukui (Japan)

2017-04-15

During a molten core–concrete interaction, molten oxides consisting of molten core materials (UO{sub 2} and ZrO{sub 2}) and concrete (Al{sub 2}O{sub 3}, SiO{sub 2}, CaO) are formed. Reliable data on the physical properties of the molten oxides will allow us to accurately predict the progression of a nuclear reactor core meltdown accident. In this study, the viscosities and densities of molten (ZrO{sub 2}){sub x}(Al{sub 2}O{sub 3}){sub 1-x} (x = 0.356 and 0.172) were measured using an aerodynamic levitation technique. The densities of two small samples were estimated from their masses and their volumes (calculated from recorded images of the molten samples). The droplets were forced to oscillate using speakers, and their viscosities were evaluated from the damping behaviors of their oscillations. The results showed that the viscosity of molten (ZrO{sub 2}){sub x}(Al{sub 2}O{sub 3}){sub 1-x} compared to that of pure molten Al{sub 2}O{sub 3} is 25% lower for x = 0.172, while it is unexpectedly 20% higher for x = 0.356. - Highlights: •The physical properties of molten (ZrO{sub 2}){sub x}(Al{sub 2}O{sub 3}){sub 1-x} (x = 0.356 and 0.172) have been evaluated. •The measurement was conducted using an aerodynamic levitation technique. •The density and viscosity were measured.

Study on the phosphate reaction characteristics of lanthanide chlorides in molten salt with operating conditions

International Nuclear Information System (INIS)

Lee, Tae-Kyo; Hwang, Taek-Sung; Cho, Yung-Zun; Eun, Hee-Chul; Park, Hwan-Seo; Park, Geun-Il; Son, Sung-Mo

2013-01-01

A minimization of waste salt is one of the most important issues for the optimization of pyroprocessing. The separation of fission products in waste salts and the reuse of purified waste salt are promising strategies for minimizing the waste salt amounts. The phosphate precipitation of lanthanide is currently being considered for eutectic (LiCl–KCl) waste salt purification. In this research, the effects of molten salt temperature (400–550°C) and reaction time (max. 180 min) upon conversion into the phosphate of lanthanides was investigated using 1 and 3 kg of eutectic salt. The conversion efficiency of lanthanides to molten salt-insoluble precipitates and phosphates was increased with an increase in molten salt temperature and operating time until it attained a specific temperature and time. K 3 PO 4 as a precipitant was more favorable than Li 3 PO 4 in terms of reactivity. To obtain over a 99% overall conversion efficiency, about 30 min was required in the case of using K 3 PO 4 at 450°C, but about 120 min in the case of using Li 3 PO 4 at 550°C. The lanthanide precipitates formed by a reaction with phosphate were a mixture of monoclinic structures, usually representing a polyhedron structure, and a tetragonal structure, representing a platelet structure. (author)

In situ spectroscopy and spectroelectrochemistry of uranium in high-temperature alkali chloride molten salts.

Science.gov (United States)

Polovov, Ilya B; Volkovich, Vladimir A; Charnock, John M; Kralj, Brett; Lewin, Robert G; Kinoshita, Hajime; May, Iain; Sharrad, Clint A

2008-09-01

Soluble uranium chloride species, in the oxidation states of III+, IV+, V+, and VI+, have been chemically generated in high-temperature alkali chloride melts. These reactions were monitored by in situ electronic absorption spectroscopy. In situ X-ray absorption spectroscopy of uranium(VI) in a molten LiCl-KCl eutectic was used to determine the immediate coordination environment about the uranium. The dominant species in the melt was [UO 2Cl 4] (2-). Further analysis of the extended X-ray absorption fine structure data and Raman spectroscopy of the melts quenched back to room temperature indicated the possibility of ordering beyond the first coordination sphere of [UO 2Cl 4] (2-). The electrolytic generation of uranium(III) in a molten LiCl-KCl eutectic was also investigated. Anodic dissolution of uranium metal was found to be more efficient at producing uranium(III) in high-temperature melts than the cathodic reduction of uranium(IV). These high-temperature electrolytic processes were studied by in situ electronic absorption spectroelectrochemistry, and we have also developed in situ X-ray absorption spectroelectrochemistry techniques to probe both the uranium oxidation state and the uranium coordination environment in these melts.

Thermodynamic properties of LiCl solutions in N-methylacetamide at 308.15-328.15 K

Science.gov (United States)

Manin, N. G.; Kolker, A. M.

2017-12-01

Enthalpies of dissolution of crystalline LiCl and enthalpies of dilution of LiCl solutions in N-methylacetamide (NMA) with electrolyte concentrations no greater than 0.32 m are measured on an isoperibolic calorimeter at 308.15, 318.15, and 328.5 K. Standard enthalpies of the dissolution of LiCl in NMA are calculated at different temperatures. The thermodynamic properties of the solution and its components are calculated and analyzed in the investigated range of concentrations and temperatures.

Extensive Gustatory Cortex Lesions Significantly Impair Taste Sensitivity to KCl and Quinine but Not to Sucrose in Rats.

Directory of Open Access Journals (Sweden)

Michelle B Bales

Full Text Available Recently, we reported that large bilateral gustatory cortex (GC lesions significantly impair taste sensitivity to salts in rats. Here we extended the tastants examined to include sucrose and quinine in rats with ibotenic acid-induced lesions in GC (GCX and in sham-operated controls (SHAM. Presurgically, immediately after drinking NaCl, rats received a LiCl or saline injection (i.p., but postsurgical tests indicated a weak conditioned taste aversion (CTA even in controls. The rats were then trained and tested in gustometers to discriminate a tastant from water in a two-response operant taste detection task. Psychometric functions were derived for sucrose, KCl, and quinine. Our mapping system was used to determine placement, size, and symmetry of the lesions (~91% GC damage on average. For KCl, there was a significant rightward shift (ΔEC50 = 0.57 log10 units; p<0.001 in the GCX psychometric function relative to SHAM, replicating our prior work. There was also a significant lesion-induced impairment (ΔEC50 = 0.41 log10 units; p = 0.006 in quinine sensitivity. Surprisingly, taste sensitivity to sucrose was unaffected by the extensive lesions and was comparable between GCX and SHAM rats. The fact that such large bilateral GC lesions did not shift sucrose psychometric functions relative to SHAM, but did significantly compromise quinine and KCl sensitivity suggests that the neural circuits responsible for the detection of specific taste stimuli are partially dissociable. Lesion-induced impairments were observed in expression of a postsurgical CTA to a maltodextrin solution as assessed in a taste-oriented brief-access test, but were not reflected in a longer term 46-h two-bottle test. Thus, deficits observed in rats after extensive damage to the GC are also dependent on the test used to assess taste function. In conclusion, the degree to which the GC is necessary for the maintenance of normal taste detectability apparently depends on the chemical and

Structural Analysis of Molten NaNO3 by Molecular Dynamics Simulation

Science.gov (United States)

Tahara, Shuta; Toyama, Hiroshi; Shimakura, Hironori; Fukami, Takanori

2017-08-01

MD simulation for molten NaNO3 has been performed by using the Born-Mayer-Huggins-type potentials. The new structural features of molten NaNO3 are investigated by several analytical methods. The coordination-number and bond-angle distributions are similar to those of simple molten salts such as NaCl except for the variation caused by the different size of the anion and cation. Na+ ions are attracted toward O- ions, and get separated from N+ ions by Coulomb interactions. The distribution of the dihedral angle between NO3 - plannar ionic molecules has also been investigated.

Integrated Data Collection Analysis (IDCA) Program — KClO₃ (as received)/Icing Sugar

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL/RXQL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Inc., Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whipple, Richard E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-05-23

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO₃ as received from the manufacturer mixed with icing sugar, sized through a 100-mesh sieve—KClO₃/icing sugar (AR) mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solid materials. The mixture was found to: 1) be more sensitive to impact than RDX, similar to PETN, 2) be the same or less sensitive to friction than PETN, and 3) to be less sensitive to spark than RDX. The thermal analysis showed that the mixture has thermally stability similar to RDX and is perhaps more energetic upon decomposition but variable results indicate sampling issues. Compared to the 100-mesh sieved counter part, the KClO₃/icing sugar (-100) mixture, the AR mixture was found to be about the same sensitivity towards impact, friction and ESD.

Molten metal feed system controlled with a traveling magnetic field

International Nuclear Information System (INIS)

Praeg, W.F.

1991-01-01

This patent describes a continuous metal casting system in which the feed of molten metal controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir

Phase relations in the hydrous CMAS pyrolite in presence of KCl at 2 GPa

Science.gov (United States)

Safonov, O.

2012-04-01

In the upper mantle, chlorides are constituents of concentrated aqueous solutions (brines), as well as chloride-carbonate and carbonatite melts. Mineral assemblages coming from diverse depth levels show that mobile (K, Na)Cl-bearing fluids are able to provoke intensive metasomatism of the peridotitic mantle accompanied by melting. Scarce experimental studies on influence of brines on mineral equilibria in the peridotitic mantle (Stalder et al., 2008; Chu et al., 2011) indicate that influence of chlorides on water activity in a fluid equilibrated with forsterite enstatite at pressures above 2 GPa is very similar to their effect at lower "crustal" pressures (e.g. Aranovich, Newton, 1997): decrease of the H2O activity with an increase of the salt content results in an increase of the melting temperature of silicates. Nevertheless, these experiments were performed in the Al-free systems. Presence of Al would provoke an active interaction of alkali chlorides, namely KCl, with silicates with formation of new K-Al-bearing phases, such as phlogopite (in presence of H2O), which would influence on the melting of complex assemblages. In order to investigate an effect of KCl on phase relations in the Al2O3, CaO, Na2O-rich hydrous peridotite and on stability of garnet, pyroxenes, and amphiboles, in particular, experiments on interaction of the model CMAS pyrolite Fo57En17Prp14Di12 (+0.3 wt. % of Na2O) with the H2O-KCl fluid were performed at 2 GPa in the temperature interval 900-1200. Mixtures of synthetic forsterite, diopside, enstatite and pyrope in the above weight ratio were mixed with 14 wt. % of Mg(OH)2 corresponding to 4.4 wt. % of H2O in the system. 2.4, 3.7, 5 and 10 wt. % of KCl were added to silicate-H2O mixture. Experiments were performed using a piston-cylinder apparatus with ½-inch talc high-pressure cells calibrated via brucite = periclase + H2O and albite = jadeite + quartz equilibria curves. Temperature was controlled with accuracy ?1 with the W95Re5/W80Re20

Growth inhibitor of E. coli K-12 in a sample of 39KCl

International Nuclear Information System (INIS)

Luckey, T.D.

1984-01-01

Growth rates and total population of E. coli were reduced fourfold when natural KCl (/sup N/KCl) in the medium was replaced by 39 KCl from a particular source. A prolonged lag period was noted in cultures containing either /sup N/KCl or 39 KCl when inoculated with bacteria adapted to 39 KCl. These changes were not due to endogenous radiation because these differences were not observed when (a) the KCl concentrations were reduced from 50 to 5 mM and (b) the 39 KCl from the prime source was replaced with 39 KCl from a second source; also the addition of 40 KCl to 39 KCl did not improve growth. These results suggest that the 39 KCl from the primary source contained an unidentified inhibitor that is not readily detected by physical and chemical analyses. 8 references, 3 figures, 2 tables

Following the electroreduction of uranium dioxide to uranium in LiCl–KCl eutectic in situ using synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Brown, L.D.; Abdulaziz, R.; Jervis, R.; Bharath, V.J. [Electrochemical Innovation Lab, Dept. Chemical Engineering, UCL, London WC1E 7JE (United Kingdom); Atwood, R.C.; Reinhard, C.; Connor, L.D. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Simons, S.J.R.; Inman, D.; Brett, D.J.L. [Electrochemical Innovation Lab, Dept. Chemical Engineering, UCL, London WC1E 7JE (United Kingdom); Shearing, P.R., E-mail: p.shearing@ucl.ac.uk [Electrochemical Innovation Lab, Dept. Chemical Engineering, UCL, London WC1E 7JE (United Kingdom)

2015-09-15

Highlights: • We investigated the electroreduction of UO{sub 2} to U in LiCl/KCL eutectic molten salt. • Combined electrochemical measurement and in situ XRD is utilised. • The electroreduction appears to occur in a single, 4-electron-step, process. • No intermediate compounds were observed. - Abstract: The electrochemical reduction of uranium dioxide to metallic uranium has been investigated in lithium chloride–potassium chloride eutectic molten salt. Laboratory based electrochemical studies have been coupled with in situ energy dispersive X-ray diffraction, for the first time, to deduce the reduction pathway. No intermediate phases were identified using the X-ray diffraction before, during or after electroreduction to form α-uranium. This suggests that the electrochemical reduction occurs via a single, 4-electron-step, process. The rate of formation of α-uranium is seen to decrease during electrolysis and could be a result of a build-up of oxygen anions in the molten salt. Slow transport of O{sup 2−} ions away from the UO{sub 2} working electrode could impede the electrochemical reduction.

Electrochemical behavior for a reduction of uranium oxide in a LiCl-Li2O molten salt with an integrated cathode assembly

International Nuclear Information System (INIS)

Park, Sung Bin; Park, Byung Heung; Seo, Chung Seok; Jung, Ki Jung; Park, Seong Won

2005-01-01

Electrolytic reduction of uranium oxide to uranium metal was studied in a LiCl-Li 2 O molten salt system. The reduction mechanism of the uranium oxide to a uranium metal has been studied by means of a cyclic voltammetry. Effects of the layer thickness of the uranium oxide and the thickness of the MgO on the overpotential of the cathode and the anode were investigated by means of a chronopotentiometry. From the cyclic voltamograms, the decomposition potentials of the metal oxides are the determining factors for the mechanism of the reduction of the uranium oxide in a Li Cl-3 wt% Li 2 O molten salt and the two mechanisms of the electrolytic reduction were considered with regards to the applied cathode potential. In the chronopotentiograms, the exchange current and the transfer coefficient based on the Tafel behavior were obtained with regard to the layer thickness of the uranium oxide which is loaded into the porous MgO membrane and the thickness of the porous MgO membrane. The maximum allowable currents for the changes of the layer thickness of the uranium oxide and the thickness of the MgO membrane were also obtained from the limiting potential which is the decomposition potential of LiCl

Molten salt reactor technology for long-range and wide-scale nuclear energy system

International Nuclear Information System (INIS)

Ignatiev, V.; Alexseev, P.; Menshikov, L.; Prusakov, V.; Subbotine, S.

1997-01-01

A possibility of creation of multi-component nuclear power system in which alongside with thermal and fast reactors, molten salt burner reactors, for incineration of weapon grade plutonium, some minor actinides and transmutation of some fission products will be presented. The purposes of this work are to review the present status of the molten salt reactor technology and innovative non-aqueous chemical processing methods, to indicate the importance of the uncertainties remaining, to identify the additional work needed, and to evaluate the probability of success in obtaining improved safety characteristics for new concept of molten salt - burner reactor with external neutron source. 8 refs., 3 figs., 2 tabs

A new form of MgTa2O6 obtained by the molten salt method

Indian Academy of Sciences (India)

Unknown

Abstract. Using molten salt route (with NaCl/KCl as the salt) we have been able to synthesize a new form of magnesium tantalate at 850°C. Powder X-ray diffraction data could be indexed on an orthorhombic unit cell with lattice parameters, 'a' = 15⋅36(1) Å, 'b' = 13⋅38(1) Å and 'c' = 12⋅10(1) Å. High resolution.

Investigation of molten metal droplet deposition and solidification for 3D printing techniques

International Nuclear Information System (INIS)

Wang, Chien-Hsun; Tsai, Ho-Lin; Wu, Yu-Che; Hwang, Weng-Sing

2016-01-01

This study investigated the transient transport phenomenon during the pile up of molten lead-free solder via the inkjet printing method. With regard to the droplet impact velocity, the distance from nozzle to substrate can be controlled by using the pulse voltage and distance control apparatus. A high-speed digital camera was used to record the solder impact and examine the accuracy of the pile up. These impact conditions correspond to We  =  2.1–15.1 and Oh  =  5.4  ×  10 −3 –3.8  ×  10 −3 . The effects of impact velocity and relative distance between two types of molten droplets on the shape of the impact mode are examined. The results show that the optimal parameters of the distance from nozzle to substrate and the spreading factor in this experiment are 0.5 mm and 1.33. The diameter, volume and velocity of the inkjet solder droplet are around 37–65 μ m, 25–144 picoliters, and 2.0–3.7 m s −1 , respectively. The vertical and inclined column structures of molten lead-free solder can be fabricated using piezoelectric ink-jet printing systems. The end-shapes of the 3D micro structure have been found to be dependent upon the distance from nozzle to substrate and the impact velocity of the molten lead-free solder droplet. (paper)

Electrodeposition of Al-Mn alloy on AZ31B magnesium alloy in molten salts

International Nuclear Information System (INIS)

Zhang Jifu; Yan Chuanwei; Wang Fuhui

2009-01-01

The Al-Mn alloy coatings were electrodeposited on AZ31B Mg alloy in AlCl 3 -NaCl-KCl-MnCl 2 molten salts at 170 deg. C aiming to improve the corrosion resistance. However, in order to prevent AZ31B Mg alloy from corrosion during electrodeposition in molten salts and to ensure excellent adhesion of coatings to the substrate, AZ31B Mg alloy should be pre-plated with a thin zinc layer as intermediate layer. Then the microstructure, composition and phase constituents of the coatings were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD). It was indicated that, by adjusting the MnCl 2 content in the molten salts from 0.5 wt% to 2 wt%, the Mn content in the alloy coating was increased and the phase constituents were changed from f.c.c Al-Mn solid solution to amorphous phase. The corrosion resistance of the coatings was evaluated by potentiodynamic polarization measurements in 3.5% NaCl solution. It was confirmed that the Al-Mn alloy coatings exhibited good corrosion resistance with a chear passive region and significantly reduced corrosion current density at anodic potentiodynamic polarization. The corrosion resistance of the alloy coatings was also related with the microstructure and Mn content of the coatings.

Absorption of water vapour in the falling film of water-(LiBr + LiI + LiNO{sub 3} + LiCl) in a vertical tube at air-cooling thermal conditions

Energy Technology Data Exchange (ETDEWEB)

Bourouis, Mahmoud; Valles, Manel; Medrano, Marc; Coronas, Alberto [Centro de Innovacion Tecnologica en Revalorizacion Energetica y Refrigeracion, CREVER, Universitat Rovira i Virgili, Autovia de Salou, s/n, 43006, Tarragona (Spain)

2005-05-01

In air-cooled water-LiBr absorption chillers the working conditions in the absorber and condenser are shifted to higher temperatures and concentrations, thereby increasing the risk of crystallisation. To develop this technology, two main problems are to be addressed: the availability of new salt mixtures with wider range of solubility than water-LiBr, and advanced absorber configurations that enable to carry out simultaneously an appropriate absorption process and an effective air-cooling. One way of improving the solubility of LiBr aqueous solutions is to add other salts to create multicomponent salt solutions. The aqueous solution of the quaternary salt system (LiBr + LiI + LiNO{sub 3} + LiCl) presents favourable properties required for air-cooled absorption systems: less corrosive and crystallisation temperature about 35 K lower than that of water-LiBr.This paper presents an experimental study on the absorption of water vapour over a wavy laminar falling film of an aqueous solution of (LiBr + LiI + LiNO{sub 3} + LiCl) on the inner wall of a water-cooled smooth vertical tube. Cooling water temperatures in the range 30-45 C were selected to simulate air-cooling thermal conditions. The results are compared with those obtained in the same experimental set-up with water-LiBr solutions.The control variables for the experimental study were: absorber pressure, solution Reynolds number, solution concentration and cooling water temperature. The parameters considered to assess the absorber performance were: absorber thermal load, mass absorption flux, degree of subcooling of the solution leaving the absorber, and the falling film heat transfer coefficient.The higher solubility of the multicomponent salt solution makes possible the operation of the absorber at higher salt concentration than with the conventional working fluid water-LiBr. The absorption fluxes achieved with water-(LiBr + LiI + LiNO{sub 3} + LiCl) at a concentration of 64.2 wt% are around 60 % higher than

Thermal Characterization of Molten Salt Systems

Energy Technology Data Exchange (ETDEWEB)

Toni Y. Gutknecht; Guy L. Fredrickson

2011-09-01

The phase stability of molten salts in an electrorefiner (ER) may be adversely affected by the buildup of sodium, fission products, and transuranics in the electrolyte. Potential situations that need to be avoided are the following: (1) salt freezing due to an unexpected change in the liquidus temperature, (2) phase separation or non-homogeneity of the molten salt due to the precipitation of solids or formation of immiscible liquids, and (3) any mechanism that can result in the separation and concentration of fissile elements from the molten salt. Any of these situations would result in an off-normal condition outside the established safety basis for electrorefiner (ER) operations. The stability (and homogeneity) of the phases can potentially be monitored through the thermal characterization of the salts, which can be a function of impurity concentration. This report describes the experimental results of typical salts compositions, which consist of chlorides of potassium, lithium, strontium, samarium, praseodymium, lanthanum, barium, cerium, cesium, neodymium, sodium and gadolinium chlorides as a surrogate for both uranium and plutonium, used for the processing of used nuclear fuels.

Direct reduction of uranium dioxide and few other metal oxides to corresponding metals by high temperature molten salt electrolysis

International Nuclear Information System (INIS)

Mohandas, K.S.

2017-01-01

Molten salt based electro-reduction processes, capable of directly converting solid metal oxides to metals with minimum intermediate steps, are being studied worldwide. Production of metals apart, the process assumes importance in nuclear technology in the context of pyrochemical reprocessing of spent oxide fuels, for it serves as an intermediate step to convert spent oxide fuel to a metal alloy, which in turn can be processed by molten salt electro-refining method to gain the actinides present in it. In the context of future metal fuel fast reactor programme, the electrochemical process was studied for conversion of solid UO_2 to U metal in LiCl-1wt.% Li_2O melt at 650 °C with platinum anode at the Metal Processing Studies Section, PMPD, IGCAR. A brief overview of the work is presented in the paper

Calorimetric study of water's two glass transitions in the presence of LiCl

Science.gov (United States)

Ruiz, Guadalupe N.; Amann-Winkel, Katrin; Bove, Livia E.; Corti, Horacio R.

2018-01-01

A DSC study of dilute glassy LiCl aqueous solutions in the water-dominated regime provides direct evidence of a glass-to-liquid transition in expanded high density amorphous (eHDA)-type solutions. Similarly, low density amorphous ice (LDA) exhibits a glass transition prior to crystallization to ice Ic. Both glass transition temperatures are independent of the salt concentration, whereas the magnitude of the heat capacity increase differs. By contrast to pure water, the glass transition endpoint for LDA can be accessed in LiCl aqueous solutions above 0.01 mole fraction. Furthermore, we also reveal the endpoint for HDA's glass transition, solving the question on the width of both glass transitions. This suggests that both equilibrated HDL and LDL can be accessed in dilute LiCl solutions, supporting the liquid–liquid transition scenario to understand water's anomalies. PMID:29442107

Characterization of pack cemented Ni₂Al₃ coating exposed to KCl(s) induced corrosion at 600 °C

DEFF Research Database (Denmark)

Dahl, Kristian Vinter; Slomian, A.; Lomholt, Trine Nybo

2018-01-01

Ni2Al3 shows minimal weight gain, while adding KCl results in a small weight loss consistent with evaporation of KCl. On the surface of samples exposed to the gas environment only, a 30 nm oxide of Al oxide was present, but where KCl was present as deposit, 50–250 nm thick nodules form...

On chlorization of uranium and plutonium oxides in NaCl-KCl-MgCl2 molten eutectic

International Nuclear Information System (INIS)

Vorobej, M.P.; Desyatnik, V.N.; Pirogov, S.M.

1978-01-01

The chlorination process of U 3 O 8 , UO 2 , and PuO 2 in a melt of anhydrous NaCl-KCl-MgCl 2 with gaseous chlorine and carbon tetrachloride has been studied. The chlorination rate of uranium oxides has been studied within a temperature range 500-800 deg C at a chlorine feeding rate of 10 ml/min. Thermoqravimetric and X-ray analyses have shown that K 2 UO 2 Cl 4 compound is the final product of chlorination of uranium oxides. The mechanism of chlorination has been proposed. THe rate of PuO 2 chlorination has been studied within the same temperature range. It has been established that PuO 2 is readily chlorinated with CCl 4 vapours at a feeding rate of 10 ml/min. In contrast to uranium, chloride forms of plutonium in a highest oxidized state are unstable and are reduced in the melt to Pu(3) and Pu(4). The oxygen being released is retained by CCl 4 and by the products of CCl 4 pyrolysis

Electron paramagnetic resonance of K3Rh(CN)6 irradiated with electrons in KCl

International Nuclear Information System (INIS)

Vugman, N.V.

1970-07-01

Using a simple theory, it was estimated the electronic density of the diamagnetic complex Rh (CN) 3- 6 in a KCl lattice. The g// and g1 values were determined by EPR, and the experimental results fit the theoretical calculations. (M.W.O.) [pt

New colour centres in KCl:(Tl+ + Ca2+) and KCl:(Tl+ + Sr2+) crystals

International Nuclear Information System (INIS)

Ioan, A.; Topa, V.; Giurgea, M.

1978-01-01

Electrolytic colouring under unusual conditions (low temperature and high voltage) gives rise to the appearance of three new absorption bands peaking at 3.2, 2.5, and 1.7 eV and at 2.8, 2.1, and 1.5 eV in KCl:(Tl + + Ca 2+ ) and in KCl:(Tl + + Sr 2+ ) single crystals, respectively. The modifications of the absorption spectra of the coloured crystals induced by the application of a reversed electric field at the colouring temperature or by heat treatment are investigated. It is likely that the colour centre responsible for the new absorption bands is an aggregate centre which, besides an Tl - -complex, contains also at least an Ca(Sr) ion, a trapped electron, and an anionic vacancy. (author)

Vibrational spectroscopy of hydrated potassium hexauranate for the phase study of the UO3-KCl-H2O system

International Nuclear Information System (INIS)

Dothee, Daniel.

1980-02-01

In the study of the UO 3 -KCl-H 2 O system, a phase, called C phase, was isolated; it has a radiocrystallogram very close to the hexauranate K 2 U 6 O 19 ,11H 2 O, but K + and Cl - are found in its composition. Links between these two phases are studied and especially structure relationships. Hydrated potassium hexauranate structure was determined previously with a natural crystal. Position of potassium and uranium atoms only are known. As monocrystal preparation is impossible a direct structural study is impossible too. Vibrational spectroscopic analysis was selected for this study. Hexauranate structure is determined and results are extended for the study of the C phase. The hydrate UO 3 .0.8 H 2 O a stable and well defined compound is chosen for the hydrothermal synthesis of the different phases. Four main phases are evidenced: the chloro-uranate Ksub(x)UO 3 Clsub(x) (already known), a hydrated potassium uranate and two phases (one is the C phase) containing chloride ions are intermediaries between the chloro-uranate and the uranate [fr

The corrosion behavior of mild steel in molten NaNO3-KNO3 salt and its evaluation

International Nuclear Information System (INIS)

Tsujino, Bunzo; Oki, Takeo.

1992-01-01

The galvanic behavior of mild steel in molten NaNO 3 -KNO 3 salt (equivalent molar fraction) and its evaluation have been investigated by the amount of galvanic current with zero impedance ammeter. The galvanic currents in a galvanic couple consisting of mild steel and platinum so obtained corresponded approximately to the information for dissolution reaction of iron in molten NaNO 3 KNO 3 salt. Further, the galvanic currents proved to be an effective means for evaluating corrosion rate of metals in molten NaNO 3 KNO 3 salt. The effect of NaCl on galvanic behavior of mild steel couple to platinum in molten NaNO 3 -KNO 3 salt did not appear at the NaCl concentration up to 0.05 molar fraction, but the effect appeared as localized corrosion at the NaCl concentration of 0.05 molar fraction or more. The coloration for mild steel due to the oxide film was well controlled by adjusting amount of electricity rather than the temperature. (author)

Mechanism of norepinephrine release elicited by renal nerve stimulation, veratridine and potassium chloride in the isolated rat kidney

International Nuclear Information System (INIS)

el-Din, M.M.; Malik, K.U.

1987-01-01

We have investigated the mechanism by which renal nerve stimulation (RNS), veratridine (Vt) and KCl promote release of norepinephrine in the isolated rat kidney perfused with Tyrode's solution and prelabeled with [ 3 H]norepinephrine by examining the overflow of tritium elicited by these stimuli during 1) extracellular Ca++ depletion, 2) alterations in extracellular Na+ concentration and 3) administration of tetrodotoxin, amiloride, LiCl and calcium channel blockers. RNS (1-4 Hz), Vt (15-90 nmol) and KCl (150-500 mumol) produced renal vasoconstriction and enhanced the tritium overflow in a frequency- and concentration-dependent manner, respectively. Omission of Ca++ (1.8 mM) from the perfusion fluid abolished the renal vasoconstriction and the increase in tritium overflow elicited by RNA and KCl and substantially reduced that caused by Vt. Lowering the Na+ concentration in the perfusion medium (from 150 to 25 mM) reduced the overflow of tritium and the renal vasoconstriction caused by RNS (2 Hz) or Vt (45 nmol); the increase in tritium overflow in response to these stimuli was positively correlated with extracellular Na+ (25-150 mM). In contrast, KCl-induced tritium overflow was negatively correlated with extracellular Na+ concentration. Tetrodotoxin (0.3 microM) abolished the effect of RNS and Vt, but not that of KCl, to increase overflow of tritium and to produce renal vasoconstriction. Administration of amiloride (180 microM) enhanced the overflow of tritium but attenuated the associated renal vasoconstriction produced by RNS, Vt and KCl. Replacement of NaCl (75 mM) with equimolar concentration of LiCl enhanced the overflow of tritium elicited by RNS, Vt and KCl; the associated renal vasoconstriction remained unaltered

Characterization and electrochemical properties of high tap-density LiFePO4/C cathode materials by a combination of carbothermal reduction and molten salt methods

International Nuclear Information System (INIS)

Fey, George Ting-Kuo; Lin, Yi-Chuan; Kao, Hsien-Ming

2012-01-01

Olivine-structured LiFePO 4 cathode materials were prepared via a combination of carbothermal reduction (CR) and molten salt (MS) methods. To enhance the powder's tap density, the LiFePO 4 /C composite was pressed into pellets and then sintered for at least 1 h at 1028 K in the reaction environment of KCl molten salts. The use of molten salt can effectively influence unit cell volume, morphology and tap density of particles, and consequently change the electrochemical performance of LiFePO 4 /C. The composites were characterized in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Raman spectroscopy and tap density testing. The final product with high tap density of 1.50 g cm −3 contains 4.58 wt% carbon and exhibits good discharge capacity of 141 mAh g −1 at a 0.2 C-rate in the potential range of 2.8–4.0 V.

Platelet-derived growth factor regulates K-Cl cotransport in vascular smooth muscle cells.

Science.gov (United States)

Zhang, Jing; Lauf, Peter K; Adragna, Norma C

2003-03-01

Platelet-derived growth factor (PDGF), a potent serum mitogen for vascular smooth muscle cells (VSMCs), plays an important role in membrane transport regulation and in atherosclerosis. K-Cl cotransport (K-Cl COT/KCC), the coupled-movement of K and Cl, is involved in ion homeostasis. VSMCs possess K-Cl COT activity and the KCC1 and KCC3 isoforms. Here, we report on the effect of PDGF on K-Cl COT activity and mRNA expression in primary cultures of rat VSMCs. K-Cl COT was determined as the Cl-dependent Rb influx and mRNA expression by semiquantitative RT-PCR. Twenty four-hour serum deprivation inhibited basal K-Cl COT activity. Addition of PDGF increased total protein content and K-Cl COT activity in a time-dependent manner. PDGF activated K-Cl COT in a dose-dependent manner, both acutely (10 min) and chronically (12 h). AG-1296, a selective inhibitor of the PDGF receptor tyrosine kinase, abolished these effects. Actinomycin D and cycloheximide had no effect on the acute PDGF activation of K-Cl COT, suggesting posttranslational regulation by the drug. Furthermore, PDGF increased KCC1 and decreased KCC3 mRNA expression in a time-dependent manner. These results indicate that chronic activation of K-Cl COT activity by PDGF may involve regulation of the two KCC mRNA isoforms, with KCC1 playing a dominant role in the mechanism of PDGF-mediated activation.

Solubility of 1:1 Alkali Nitrates and Chlorides in Near-Critical and Supercritical Water : 1 Alkali Nitrates and Chlorides in Near-Critical and Supercritical Water

NARCIS (Netherlands)

Leusbrock, Ingo; Metz, Sybrand J.; Rexwinkel, Glenn; Versteeg, Geert F.

2009-01-01

To increase the available data oil systems containing supercritical water and inorganic compounds, all experimental setup was designed to investigate the solubilities of inorganic compounds Ill supercritical water, In this work, three alkali chloride salts (LiCl, NaCl, KCl) and three alkali nitrate

Molten fluoride fuel salt chemistry

International Nuclear Information System (INIS)

Toth, L.M.; Del Cul, G.D.; Dai, S.; Metcalf, D.H.

1995-01-01

The chemistry of molten fluorides is traced from their development as fuels in the Molten Salt Reactor Experiment with important factors in their selection being discussed. Key chemical characteristics such as solubility, redox behavior, and chemical activity are explained as they relate to the behavior of molten fluoride fuel systems. Development requirements for fitting the current state of the chemistry to modern nuclear fuel system are described. It is concluded that while much is known about molten fluoride behavior which can be used effectively to reduce the amount of development required for future systems, some significant molten salt chemical questions must still be addressed. copyright American Institute of Physics 1995

Structural and optical properties of Ta{sub 2}O{sub 5}:Eu{sup 3+}: Mg{sup 2+} or Ca{sup 2+} phosphor prepared by molten salt method

Energy Technology Data Exchange (ETDEWEB)

Verma, Naveen, E-mail: vermanaveen17@gmail.com; Singh, Krishan Chander; Jindal, Jitender [Department of chemistry, Maharshi Dayanand University, Rohtak-124001 – India (India); Mari, Bernabe; Mollar, Miguel; Manjón, F. J. [Institut de Disseny per la Fabricació Automatitzada - Departament de Física Aplicada, Universitat Politècnica de València, Camí de Vera s/n, 46022 València (Spain); Rana, Ravi [Department of Chemistry, SGT University, Gurgaon (India); Pereira, A. L. J. [Universitat Politècnica de València, 46022 València (Spain)

2016-04-13

Ta{sub 2}O{sub 5}:Eu{sup 3+}: Mg{sup 2+} or Ca{sup 2+} phosphor materials were prepared by molten salt method using KCl as flux. The X-ray diffraction (XRD) patterns illustrated that the well crystallized Ta{sub 2}O{sub 5}:Eu{sup 3+}: Mg{sup 2+} or Ca{sup 2+} were formed in the presence of flux under reduced temperature (800 °C) in contrast to conventional solid state method (1200-1500 °C). Scanning electron microscope (SEM) images indicate the achievement of well dispersed particles (hexagonal tablet and rod-like structures). Meanwhile, the photo-luminescent studies demonstrated that Ta{sub 2}O{sub 5} is an efficient host to sensitize europium red emissions. The addition of Mg{sup 2+} or Ca{sup 2+} as co-dopant enhanced the luminescent intensity of Ta{sub 2}O{sub 5}: Eu{sup 3+} compound.

Materials considerations for molten salt accelerator-based plutonium conversion systems

International Nuclear Information System (INIS)

DiStefano, J.R.; DeVan, J.H.; Keiser, J.R.; Klueh, R.L.; Eatherly, W.P.

1995-03-01

Accelerator-driven transmutation technology (ADTT) refers to a concept for a system that uses a blanket assembly driven by a source of neutrons produced when high-energy protons from an accelerator strike a heavy metal target. One application for such a system is called Accelerator-Based Plutonium Conversion, or ABC. Currently, the version of this concept being proposed by the Los Alamos National Laboratory features a liquid lead target material and a blanket fuel of molten fluorides that contain plutonium. Thus, the materials to be used in such a system must have, in addition to adequate mechanical strength, corrosion resistance to molten lead, corrosion resistance to molten fluoride salts, and resistance to radiation damage. In this report the corrosion properties of liquid lead and the LiF-BeF 2 molten salt system are reviewed in the context of candidate materials for the above application. Background information has been drawn from extensive past studies. The system operating temperature, type of protective environment, and oxidation potential of the salt are shown to be critical design considerations. Factors such as the generation of fission products and transmutation of salt components also significantly affect corrosion behavior, and procedures for inhibiting their effects are discussed. In view of the potential for extreme conditions relative to neutron fluxes and energies that can occur in an ADTT, a knowledge of radiation effects is a most important factor. Present information for potential materials selections is summarized

Materials considerations for molten salt accelerator-based plutonium conversion systems

International Nuclear Information System (INIS)

DiStefano, J.R.; DeVan, J.H.; Keiser, J.R.; Klueh, R.L.; Eatherly, W.P.

1995-02-01

Accelerator-driven transmutation technology (ADTT) refers to a concept for a system that uses a blanket assembly driven by a source of neutrons produced when high-energy protons from an accelerator strike a heavy metal target. One application for such a system is called Accelerator-Based Plutonium Conversion, or ABC. Currently, the version of this concept being proposed by the Los Alamos National Laboratory features a liquid lead target material and a blanket fuel of molten fluorides that contain plutonium. Thus, the materials to be used in such a system must have, in addition to adequate mechanical strength, corrosion resistance to molten lead, corrosion resistance to molten fluoride salts, and resistance to radiation damage. In this report the corrosion properties of liquid lead and the LiF-BeF 2 molten salt system are reviewed in the context of candidate materials for the above application. Background information has been drawn from extensive past studies. The system operating temperature, type of protective environment, and oxidation potential of the salt are shown to be critical design considerations. Factors such as the generation of fission products and transmutation of salt components also significantly affect corrosion behavior, and procedures for inhibiting their effects are discussed. In view of the potential for extreme conditions relative to neutron fluxes and energies that can occur in an ADTT, a knowledge of radiation effects is a most important factor. Present information for potential materials selections is summarized

On the impedance of galvanic cells XXIV. The impedance of the In3+/In(Hg) electrode reaction in KSCN and KCl solution

NARCIS (Netherlands)

Timmer, B.; Sluyters-Rehbach, M.; Sluyters, J.H.

1968-01-01

The In3+/In(Hg) system in KSCN and KCl solutions has been investigated using both d.c. and a.c. measurements. The experimental data are analysed and interpreted according to theoretical equations presented recently. It is shown that the specific adsorption of indium from 1 M KSCN follows a linear

Measurements of pressure for the TiH/sub x//KClO4 system

International Nuclear Information System (INIS)

Chong, C.H.H.; Glaub, J.E.

1978-01-01

An investigation was conducted to measure the pressure obtained when the pyrotechnic mixture TiH/sub x//KClO 4 was ignited in a confined variable-volume system. It was possible to derive an expression of the form PV/sup γ/ = k for the pressure-volume relationship obtained. This expression is a polytropic expansion of the ideal gas equation that best fits the data generated. For this particular work, values of γ = 0.53 and k = 69.3 were obtained where P is in megapascals and V is in cubic centimeters. In addition, estimates of the reaction rates were calculated based on the times to achieve maximum pressure for a given volume system. An explicit expression relating rate to pressure was derived by a simplified least-squares fit of the data obtained

Environmental and energy gains from using molten magnesium–sodium–potassium chlorides for electro-metallisation of refractory metal oxides

Directory of Open Access Journals (Sweden)

Wei Li

2015-12-01

Full Text Available The molten eutectic mixture of magnesium, sodium and potassium chlorides (MgCl2–NaCl–KCl has inappreciable solubility for oxide ions, and can help disengage a carbon anode from the oxide ions generated at a metal oxide cathode, and effectively avoid carbon dioxide formation. This “disengaging strategy” was successfully demonstrated in electro-reduction of solid oxides of zirconium and tantalum. It has led to significantly higher current efficiency (93%, and lower energy consumption (1.4 kW h kg−1 in electrolysis of tantalum oxide to tantalum metal compared to the conventional electrolysis in molten calcium chloride (e.g. 78% and 2.4 kW h/kg-Ta.

Processing of Vietnamese lithium ores to produce LiCl

International Nuclear Information System (INIS)

Dinh, Thi Thu Hien

2015-01-01

A potential lithium deposit has been discovered in the La Vi mining district, located in Quang Ngai Province, Central Vietnam. The Li-rich rocks (average contents: 1.3±0.9 wt.% Li 2 O) are highly fractionated, peraluminous granites, which are further characterized by high contents of Al 2 O 3 , Na 2 O, K 2 O, F, and P 2 O 5 , but very low concentrations of all other main components (MgO, CaO, Fe 2 O 3 tot, TiO 2 ). The granites exhibit a light pink color and contain mainly albite, quartz, muscovite, lithian muscovite, and lepidolite, with minor amounts of amblygonite-montebrasite, herderite, fluorapatite, topaz, and cassiterite, and accessory beryl and goyazite. Lepidolite from La Vi deposit was extracted to produce lithium chloride by using iron II sulphide (FeS)-CaO roasting and water leaching. The HSC program was applied for the simulation of the behavior of lepidolite and the additives during roasting, confirming the important role of SO 2 /SO 3 gas for extracting lithium from lepidolite. At optimum conditions roasting at 750 C using FeS/Li and Ca/F molar ratios of 5:1 and 1:1, respectively, followed by leaching at 50 C using water/calcine mass ratios of >5:1 could yield a maximum of ∝85% Li recovery (at <1 g/L Li concentration). Addition of CaO led to a decrease in the liberation of HF gas and insoluble LiF formation. NaOH and BaCl 2 were used for removing the metal and sulphate impurities from the leach liquor by precipitation at ambient temperature. The efficiency of lithium extraction reached ∝100 % with washing of the precipitates after filtering. Alkali salts were separated from the LiCl solution via solar evaporation and isopropanol leaching. 96.3 wt.% LiCl could be produced using an isopropanol/salt mass ratio of 5:1 at ambient temperature in 3 h.

Processing of Vietnamese lithium ores to produce LiCl

Energy Technology Data Exchange (ETDEWEB)

Dinh, Thi Thu Hien

2015-11-16

A potential lithium deposit has been discovered in the La Vi mining district, located in Quang Ngai Province, Central Vietnam. The Li-rich rocks (average contents: 1.3±0.9 wt.% Li{sub 2}O) are highly fractionated, peraluminous granites, which are further characterized by high contents of Al{sub 2}O{sub 3}, Na{sub 2}O, K{sub 2}O, F, and P{sub 2}O{sub 5}, but very low concentrations of all other main components (MgO, CaO, Fe{sub 2}O{sub 3}tot, TiO{sub 2}). The granites exhibit a light pink color and contain mainly albite, quartz, muscovite, lithian muscovite, and lepidolite, with minor amounts of amblygonite-montebrasite, herderite, fluorapatite, topaz, and cassiterite, and accessory beryl and goyazite. Lepidolite from La Vi deposit was extracted to produce lithium chloride by using iron II sulphide (FeS)-CaO roasting and water leaching. The HSC program was applied for the simulation of the behavior of lepidolite and the additives during roasting, confirming the important role of SO{sub 2}/SO{sub 3} gas for extracting lithium from lepidolite. At optimum conditions roasting at 750 C using FeS/Li and Ca/F molar ratios of 5:1 and 1:1, respectively, followed by leaching at 50 C using water/calcine mass ratios of >5:1 could yield a maximum of ∝85% Li recovery (at <1 g/L Li concentration). Addition of CaO led to a decrease in the liberation of HF gas and insoluble LiF formation. NaOH and BaCl{sub 2} were used for removing the metal and sulphate impurities from the leach liquor by precipitation at ambient temperature. The efficiency of lithium extraction reached ∝100 % with washing of the precipitates after filtering. Alkali salts were separated from the LiCl solution via solar evaporation and isopropanol leaching. 96.3 wt.% LiCl could be produced using an isopropanol/salt mass ratio of 5:1 at ambient temperature in 3 h.

Signal transduction mechanisms of K+-Cl- cotransport regulation and relationship to disease.

Science.gov (United States)

Adragna, N C; Ferrell, C M; Zhang, J; Di Fulvio, M; Temprana, C F; Sharma, A; Fyffe, R E W; Cool, D R; Lauf, P K

2006-01-01

The K+-Cl- cotransport (COT) regulatory pathways recently uncovered in our laboratory and their implication in disease state are reviewed. Three mechanisms of K+-Cl- COT regulation can be identified in vascular cells: (1) the Li+-sensitive pathway, (2) the platelet-derived growth factor (PDGF)-sensitive pathway and (3) the nitric oxide (NO)-dependent pathway. Ion fluxes, Western blotting, semi-quantitative RT-PCR, immunofluorescence and confocal microscopy were used. Li+, used in the treatment of manic depression, stimulates volume-sensitive K+-Cl- COT of low K+ sheep red blood cells at cellular concentrations 3 mM, causes cell swelling, and appears to regulate K+-Cl- COT through a protein kinase C-dependent pathway. PDGF, a potent serum mitogen for vascular smooth muscle cells (VSMCs), regulates membrane transport and is involved in atherosclerosis. PDGF stimulates VSM K+-Cl- COT in a time- and concentration-dependent manner, both acutely and chronically, through the PDGF receptor. The acute effect occurs at the post-translational level whereas the chronic effect may involve regulation through gene expression. Regulation by PDGF involves the signalling molecules phosphoinositides 3-kinase and protein phosphatase-1. Finally, the NO/cGMP/protein kinase G pathway, involved in vasodilation and hence cardiovascular disease, regulates K+-Cl- COT in VSMCs at the mRNA expression and transport levels. A complex and diverse array of mechanisms and effectors regulate K+-Cl- COT and thus cell volume homeostasis, setting the stage for abnormalities at the genetic and/or regulatory level thus effecting or being affected by various pathological conditions.

Design study of advanced nuclear fuel recycle system. Conceptual study of recycle system using molten salt

International Nuclear Information System (INIS)

Kakehi, I.; Shirai, N.; Hatano, M.; Kajitani, M.; Yonezawa, S.; Kawai, T.; Kawamura, F.; Tobe, K.; Takahashi, K.

1996-12-01

For the purpose of developing the future nuclear fuel recycle system, the design study of the advanced nuclear fuel recycle system is being conducted. This report describes intermediate accomplishments in the conceptual system study of the advanced nuclear fuel recycle system. Fundamental concepts of this system is the recycle system using molten salt which intend to break through the conventional concepts of purex and pellet fuel system. Contents of studies in this period are as follows, 1)feasibility study of the process by Cd-cathode for nitride fuel, 2)application study for the molten salt of low melting point (AlCl3+organic salt), 3)research for decladding (advantage of decladding by heat treatment), 4)behavior of FPs in electrorefining (behavior of iodine and volatile FP chlorides, FPs behavior in chlorination), 5)criticality analysis in electrorefiner, 6)drawing of off-gas flow diagram, 7)drawing of process machinery concept (cathode processor, vibration packing), 8)evaluation for the amounts of the high level radioactive wastes, 9)quality of the recycle fuels (FPs contamination of recycle fuel), 10)conceptual study of in-cell handling system, 11)meaning of the advanced nuclear fuel recycle system. The conceptual system study will be completed in describing concepts of the system and discussing issues for the developments. (author)

Production of uranium metal via electrolytic reduction of uranium oxide in molten LiCl and salt distillation

International Nuclear Information System (INIS)

Eun-Young Choi; Chan Yeon Won; Dae-Seung Kang; Sung-Wook Kim; Ju-Sun Cha; Sung-Jai Lee; Wooshin Park; Hun Suk Im; Jin-Mok Hur

2015-01-01

Recovery of metallic uranium has been achieved by electrolytic reduction of uranium oxide in a molten LiCl-Li 2 O electrolyte at 650 deg C, followed by the removal of the residual salt by vacuum distillation at 850 deg C. Four types of stainless steel mesh baskets, with various mesh sizes (325, 1,400 and 2,300 meshes) and either three or five ply layers, were used both as cathodes and to contain the reduced product in the distillation stage. The recovered uranium had a metal fraction greater than 98.8 % and contained no residual salt. (author)

Molten metal feed system controlled with a traveling magnetic field

Science.gov (United States)

Praeg, Walter F.

1991-01-01

A continuous metal casting system in which the feed of molten metal is controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir so that p.sub.c =p.sub.g -p.sub.m where p.sub.c is the desired pressure in the caster, p.sub.g is the gravitational pressure in the duct exerted by the force of the head of molten metal in the reservoir, and p.sub.m is the electromagnetic pressure exerted by the force of the magnetic field traveling wave produced by the linear induction motor. The invention also includes feedback loops to the linear induction motor to control the casting pressure in response to measured characteristics of the metal being cast.

Structural variety in solvated lanthanoid (III) halide complexes

International Nuclear Information System (INIS)

Deacon, G.B; Feng, T.; Scott, N.M.; Junk, P.C.; James Cook University, Townsville, QLD; Meyer, G.; Skelton, B.W.; White, A.H.

2000-01-01

Treatment of lanthanum metal with CH 2 Br 2 or CH 2 I 2 in tetrahydrofuran (thf) under ultrasound conditions yields the corresponding [LaX 3 (thf) 4 ] (X Br, I) complexes in good yield. Recrystallization of [LaBr 3 (thf) 4 ] from 1,2-dimethoxyethane (dme) or bis(2-methoxyethyl) ether (dig-lyme) generates [LaBr 2 (μ-Br)(dme) 2 ] 2 and [LaBr 2 (dig-lyme) 2 ][LaBr 4 (diglyme)]. Treatment of lanthanoid metals with hexachloroethane in dme yields [LnCl 3 (dme) 2 ] (Ln = La, Nd, Er or Yb) and in acetonitrile [YbCl 2 (MeCN) 5 ] 2 [YbCl 3 (MeCN)(-Cl) 2 YbCl 3 (MeCN)]. The reaction of Yb metal pieces with 1,2-dibromoethane in thf and dme gave single crystals of [YbBr 3 (thf) 3 ] and [YbBr 3 (dme) 2 ], respectively. The X-ray determined structure of [LaBr 3 (thf) 4 ] shows a seven-coordinate monomer with pentagonal-bipyramidal stereochemistry and apical bromide ligands. For [YbBr 3 (thf) 3 ], a monomeric structure with mer-octahedral stereochemistry is observed. In [LaBr 2 (μ-Br)(dme) 2 ] 2 , two eight-coordinate La centres are linked by two bridging bromides. The dme ligands have a trans relationship to each other, and cis terminal bromides are transoid to the bridging bromides with dodecahedral stereochemistry for La. By contrast, the 1: 1.5 diglyme adduct is found to be ionic [LaBr 2 (diglyme) 2 ][LaBr 4 (diglyme)], with an eight-coordinate bicapped trigonal-prismatic lanthanum cation and a seven-coordinate pentagonal-bipyramidal lanthanum anion. In the cation, the bromide ligands are cis to each other, and in the anion, two bromides are equatorial and two are axial. In [YbBr 3 (dme) 2 ], [YbCl 3 (dme) 2 ] and [ErCl 3 (dme) 2 ], a seven-coordinate pentagonal-bipyramidal arrangement exists with apical halogen ligands. Far-infrared data, and in particular the absence of absorptions attributable to I(La-Cl ter ), suggest that [LaCl 3 (dme)] is polymeric with six bridging chlorides per lanthanum. For [YbCl 2 (MeCN) 5 ] 2 [YbCl 3 (MeCN)(-Cl) 2 YbCl 3 -(MeCN)], a remarkable

Thermal bleaching of the V-centres in gamma irradiated KCl:Ca and KCl:Sr crystals

International Nuclear Information System (INIS)

Georgiev, G.; Popov, P.; Bakalova, N.

1982-01-01

The thermal bleaching of the Vsub(2)sup(M)-and F-bands in gamma irradiated KCl:Ca and KCl:Sr has been investigated under a linear heating with rate of 1 K/min in the temperature range from 270K up to 470K. The results show that during the bleaching the ratio between the concentrations of the F-and Vsub(2)sup(M)-centers is constant. Under the supposition that the ratio is equal to 2, oscillator strenghts of 0.61 and 0.70 have been obtained for the Vsub(2)sup(M)-centre in KCl:Sr, respectively. From the derivatives of the bleaching curves the activation energies and frequency factors for the Vsub(2)sup(M)-centre destruction has been obtained as well. (authors)

Phase equilibrium of the system Ag-Fe-Nd, and Nd extraction from magnet scraps using molten silver

International Nuclear Information System (INIS)

Takeda, O.; Okabe, T.H.; Umetsu, Y.

2004-01-01

To develop a new recycling process, we examined the direct extraction of neodymium (Nd) metal from Nd-Fe-B magnet scraps using molten silver (Ag) as an extraction medium. Prior to the extraction experiment, the phase equilibrium of the system Ag-Fe-Nd was investigated to estimate the theoretical extraction limit. It was observed that the Fe/Nd 2 Fe 17 mixture equilibrates with the molten Ag-Nd alloy containing 50-52 mol% Nd (57-59 mass% Nd) at 1363 K. The experimental results were in good agreement with the thermodynamic calculation based on literature values. By reacting Nd-Fe-B magnet scraps with molten silver at 1273 K, more than 90% of the neodymium in the scrap was extracted, and an Ag-Nd alloy containing 40-50 mass% Nd was obtained. The neodymium in the Ag-Nd alloy was separated from silver as Nd 2 O 3 by oxidizing the obtained alloy in air. Although the wettability of Nd 2 O 3 with molten silver caused some difficulties in the separation of neodymium from silver, molten silver is shown to be an effective medium for neodymium extraction from magnet scrap

Effect of Sr2+ concentration on generation of colour centres in KCl crystals

International Nuclear Information System (INIS)

Kowalczyk, J.; Damm, J.Z.

1976-01-01

Gamma radiation induced generation of F- and V-type colour centres in KCl crystals (one pure and eight Sr-doped) is examined. Beginning with about 66 ppm Sr in the sample the late colouration stage is practically suppressed. It is shown that V 2 bands are characteristic for the initial colouration stage and V 3 band for the late colouration stage. The latter band appears in the pure or low-doped KCl and in plastically deformed high-doped KCl. The introduction of fresh dislocation into the crystal either by irradiation (low-doped KCl) or by plastic deformation (high-doped KCl) is responsible for the disappearance of primary cation vacancies. Some additional data concerning the dose-rate effect and generation of F 2 (M) centres are presented. (author)

Creation of radiation defects in KCl crystals

International Nuclear Information System (INIS)

Lushchik, A.Ch.; Pung, L.A.; Khaldre, Yu.Yu.; Kolk, Yu.V.

1981-01-01

Optical and EPR methods were used to study the creation of anion and cation Frenkel defects in KCl crystals irradiated by X-ray and VUV-radiation. The decay of excitons with the creation of charged Frenkel defects (α and I centres) was detected and investigated at 4.2 K. The decay of excitons as well as the recombination of electrons with self-trapped holes leads to the creation of neutral Frenkel defects (F and H centres). The creation of Cl 3 - and Vsub(F) centres (cation vacancy is a component of these centres) by X-irradiation at 80 K proves the possibility of cation defects creation in KCl [ru

The molten salt reactors (MSR) pyro chemistry and fuel cycle for innovative nuclear systems; Congres sur les reacteurs a sels fondus (RSF) pyrochimie et cycles des combustibles nucleaires du futur

Energy Technology Data Exchange (ETDEWEB)

Brossard, Ph. [GEDEON, Groupement de Recherche CEA CNRS EDF FRAMATOME (France); Garzenne, C.; Mouney, H. [and others

2002-07-01

In the frame of the studies on next generation nuclear systems, and especially for the molten salt reactors and for the integrated fuel cycle (as IFR), the fuel cycle constraints must be taken into account in the preliminary studies of the system to improve the cycle and reactor optimisation. Among the purposes for next generation nuclear systems, sustainability and waste (radio-toxicity and mass) management are important goals. These goals imply reprocessing and recycling strategies. The objectives of this workshop are to present and to share the different strategies and scenarios, the needs based on these scenarios, the experimental facilities available today or in the future and their capabilities, the needs for demonstration. It aims at: identifying the needs for fuel cycle based on solid fuel or liquid fuel, and especially, the on-line reprocessing or clean up for the molten salt reactors; assessing the state-of-the-art on the pyro-chemistry applied to solid fuel and to present the research activities; assessing the state-of-the-art on liquid fuels (or others), and to present the research activities; expressing the R and D programs for pyro-chemistry, molten salt, and also to propose innovative processes; and proposing some joint activities in the frame of GEDEON and PRACTIS programs. This document brings together the transparencies of 18 contributions dealing with: scenario studies with AMSTER concept (Scenarios, MSR, breeders (Th) and burners); fuel cycle for innovative systems; current reprocessing of spent nuclear fuel (SNF) in molten salts (review of pyro-chemistry processes (non nuclear and nuclear)); high temperature NMR spectroscopies in molten salts; reductive extraction of An from molten fluorides (salt - liquid metal extraction); electrochemistry characterisation; characterisation with physical methods - extraction coefficient and kinetics; electrolytic extraction; dissolution-precipitation of plutonium in the eutectic LiCl-KCl (dissolution and

Regulation of K-Cl cotransport: from function to genes.

Science.gov (United States)

Adragna, N C; Di Fulvio, M; Lauf, P K

2004-10-01

This review intends to summarize the vast literature on K-Cl cotransport (COT) regulation from a functional and genetic viewpoint. Special attention has been given to the signaling pathways involved in the transporter's regulation found in several tissues and cell types, and more specifically, in vascular smooth muscle cells (VSMCs). The number of publications on K-Cl COT has been steadily increasing since its discovery at the beginning of the 1980s, with red blood cells (RBCs) from different species (human, sheep, dog, rabbit, guinea pig, turkey, duck, frog, rat, mouse, fish, and lamprey) being the most studied model. Other tissues/cell types under study are brain, kidney, epithelia, muscle/smooth muscle, tumor cells, heart, liver, insect cells, endothelial cells, bone, platelets, thymocytes and Leishmania donovani. One of the salient properties of K-Cl-COT is its activation by cell swelling and its participation in the recovery of cell volume, a process known as regulatory volume decrease (RVD). Activation by thiol modification with N-ethylmaleimide (NEM) has spawned investigations on the redox dependence of K-Cl COT, and is used as a positive control for the operation of the system in many tissues and cells. The most accepted model of K-Cl COT regulation proposes protein kinases and phosphatases linked in a chain of phosphorylation/dephosphorylation events. More recent studies include regulatory pathways involving the phosphatidyl inositol/protein kinase C (PKC)-mediated pathway for regulation by lithium (Li) in low-K sheep red blood cells (LK SRBCs), and the nitric oxide (NO)/cGMP/protein kinase G (PKG) pathway as well as the platelet-derived growth factor (PDGF)-mediated mechanism in VSMCs. Studies on VSM transfected cells containing the PKG catalytic domain demonstrated the participation of this enzyme in K-Cl COT regulation. Commonly used vasodilators activate K-Cl COT in a dose-dependent manner through the NO/cGMP/PKG pathway. Interaction between the

Gases in molten salts

CERN Document Server

Tomkins, RPT

1991-01-01

This volume contains tabulated collections and critical evaluations of original data for the solubility of gases in molten salts, gathered from chemical literature through to the end of 1989. Within the volume, material is arranged according to the individual gas. The gases include hydrogen halides, inert gases, oxygen, nitrogen, hydrogen, carbon dioxide, water vapor and halogens. The molten salts consist of single salts, binary mixtures and multicomponent systems. Included also, is a special section on the solubility of gases in molten silicate systems, focussing on slags and fluxes.

First principles study of structural, electronic and optical properties of KCl crystal

International Nuclear Information System (INIS)

Chen, Z.J.; Xiao, H.Y.; Zu, X.T.

2006-01-01

The structural, electronic and optical properties of KCl crystal in B1, B2, B3 and T1 structures have been systematically studied using first-principle pseudopotential calculations. In addition, pressure-induced phase transition has also been investigated. It was found that when the pressure is below 2.8 GPa, the B1 structure is the most stable. Above 2.8 GPa KCl crystal will undergo a structural phase transition from the relatively open NaCl structure into the more dense CsCl atomic arrangement. Our results also suggested that at about 1.2 GPa structural phase transition from B3 to T1 will occur. When the pressure arrives at 39.9 GPa, the phase transition will occur from B2 to T1. In addition, we found KCl Crystal has indirect band gap in B2 structure and direct band gap in B1, B3 and T1 structures. The band gap value is the smallest in the T1 structure and is the largest in the B1 and B3 structures. Our calculations are found to be in good agreement with available experimental and theoretical results. The dielectric function and energy loss function of KCl crystal in four structures (B1, B2, B3 and T1) have been calculated as well as the anisotropy of the optical properties of KCl crystal in T1 structure

Electrical conductivity of molten carbonate and carbonate-chloride systems coexisting with aluminium oxide powder

Energy Technology Data Exchange (ETDEWEB)

Nikolaeva, Elena V. [Institute of High Temperature Electrochemistry, Yekaterinburg (Russian Federation); Ural Federal Univ., Yekaterinburg (Russian Federation); Ural State Economic Univ., Yekaterinburg (Russian Federation); Bovet, Andrey L.; Zakiryanova, Irina D. [Institute of High Temperature Electrochemistry, Yekaterinburg (Russian Federation); Ural Federal Univ., Yekaterinburg (Russian Federation)

2018-04-01

The electrical properties of composite electrolytes (suspensions) composed of α-Al{sub 2}O{sub 3} powder and molten carbonate eutectic (Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3}-K{sub 2}CO{sub 3}){sub eut} or molten carbonate-chloride mixture 0.72(Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3}-K{sub 2}CO{sub 3}){sub eut}-0.28NaCl have been investigated by AC impedance method. This system shows a dependence of the electrical conductivity upon the temperature and the α-Al{sub 2}O{sub 3} content. The specific electrical conductivity of the α-Al{sub 2}O{sub 3}/(Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3}-K{sub 2}CO{sub 3}){sub eut} system can be adequately described by the Maxwell equation for two-phase heterogeneous materials. The regression equation for the dependence of the specific conductivity of the α-Al{sub 2}O{sub 3}/(Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3}-K{sub 2}CO{sub 3}){sub eut} composite on the aluminium oxide concentration and temperature was obtained.

Co adaptation of LiCl tolerant Solanum tuberosum L. callus cultures ...

African Journals Online (AJOL)

Jane

2011-10-12

Oct 12, 2011 ... also brings about tolerance to osmotic effects of salt. This data is highly .... These RGR values of control and LiCl adapted calli were used as reference .... by the Higher Education Commission (HEC) grants. The technical ...

Is KCl(g) corrosive at temperatures above its dew point? Influence of KCl(g) on initial stages of the high temperature corrosion of 11% Cr steel at 600 C

Energy Technology Data Exchange (ETDEWEB)

Segerdahl, K.; Pettersson, J.; Svensson, J.E.; Johansson, L.G. [Dept. of Environmental Inorganic Chemistry, High Temperature Corrosion Centre, Chalmers Univ. of Technology, Goeteborg (Sweden)

2004-07-01

The influence of gaseous KCl on the high temperature oxidation of CrMoV11 1 (X20) steel at 600 C is reported. The sample temperature was above the dew point of KCl, the partial pressure of KCl being about 5ppm. The samples were investigated by a number of surface analytical techniques including grazing angle XRD, SEM/EDX, and SAM. CrMoV11 1 steel shows protective behaviour in clean dry O{sub 2} and O{sub 2}/H{sub 2}O environment because of the formation of a chromium-rich oxide ({alpha}-(Fe,Cr){sub 2}O{sub 3}). It is often considered that alkali salts accelerate the corrosion of steel only when present on the surface in solid or liquid form. In contrast, the present result shows that gaseous KCl is very corrosive, also in the absence of condensation. KCl(g) reacts with chromium in the scale, forming K{sub 2}CrO{sub 4}(s). This depletes the protective oxide in chromium and leads to the formation of non-protective hematite, Fe{sub 2}O{sub 3}. (orig.)

Integrated Data Collection Analysis (IDCA) Program — KClO₃/Icing Sugar (-100 mesh) Mixture

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Moran, Jesse S. [Naval Surface Warfare Center (IHD-NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL/RXQF), Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whipple, Richard E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2011-05-02

The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and scanning calorimetry analysis of a mixture of KClO₃ sized through a 100-mesh sieve mixed with icing sugar, also sized through a 100-mesh sieve—KClO₃/icing sugar (-100) mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solid materials. The mixture was found to be: 1) more sensitive to impact than RDX, with sensitivity similar to PETN, 2) the same or more sensitive to friction than PETN, and 3) less sensitive to spark than RDX. The analysis showed that the mixture has thermally stability similar to RDX and is perhaps more energetic upon decomposition but variable results indicate sampling issues.

Study of effect of quenching and deformation on KCl: Gd crystals by ...

Indian Academy of Sciences (India)

Unknown

Abstract. The study of ionic conductivity vs reciprocal temperature of pure KCl and KCl crystal doped with. 0⋅1, 0⋅3 and 0⋅5 mole% gadolinium has been carried out in as grown, quenched from elevated temperatures. (100, 350 and 500°C) and annealed at various timings i.e. 2–3 h and deformed by different percentages.

Electrochemical separation of actinides and fission products in molten salt electrolyte

Energy Technology Data Exchange (ETDEWEB)

Gay, R.L.; Grantham, L.F.; Fusselman, S.P. [Rockwell International/Rocketdyne Division, Canoga Park, CA (United States)] [and others

1995-10-01

Molten salt electrochemical separation may be applied to accelerator-based conversion (ABC) and transmutation systems by dissolving the fluoride transport salt in LiCl-KCl eutectic solvent. The resulting fluoride-chloride mixture will contain small concentrations of fission product rare earths (La, Nd, Gd, Pr, Ce, Eu, Sm, and Y) and actinides (U, Np, Pu, Am, and Cm). The Gibbs free energies of formation of the metal chlorides are grouped advantageously such that the actinides can be deposited on a solid cathode with the majority of the rare earths remaining in the electrolyte. Thus, the actinides are recycled for further transmutation. Rockwell and its partners have measured the thermodynamic properties of the metal chlorides of interest (rare earths and actinides) and demonstrated separation of actinides from rare earths in laboratory studies. A model is being developed to predict the performance of a commercial electrochemical cell for separations starting with PUREX compositions. This model predicts excellent separation of plutonium and other actinides from the rare earths in metal-salt systems.

Optical investigation of gas-phase KCl/KOH sulfation in post flame conditions

DEFF Research Database (Denmark)

Weng, Wubin; chen, Shuang; Wu, Hao

2018-01-01

A counter-flow reactor setup was designed to investigate the gas-phase sulfation and homogeneous nucleation of potassium salts. Gaseous KOH and KCl were introduced into the post-flame zone of a laminar flat flame. The hot flame products mixed in the counter-flow with cold N2, with or without....... Depending on the potassium speciation in the inlet and the presence of SO2, they consisted of K2SO4, KCl, or K2CO3, respectively. The experiments showed that KOH was sulphated more readily than KCl, resulting in larger quantities of aerosols. The sulfation process in the counter-flow setup was simulated...... using a chemical kinetic model including a detailed subset for the Cl/S/K chemistry. Similar to the experimental results, much more potassium sulfate was predicted when seeding KOH compared to seeding KCl. For both KOH and KCl, sulfation was predicted to occur primarily through the reactions among...

Transient freezing of molten salts in pipe-flow systems: Application to the direct reactor auxiliary cooling system (DRACS)

International Nuclear Information System (INIS)

Le Brun, N.; Hewitt, G.F.; Markides, C.N.

2017-01-01

Highlights: • A thermo-hydraulic model has been proposed to simulate the transient freezing of molten salts in complex piping systems. • The passive safety system DRACS in Generation-IV, molten salt reactor is susceptible to failure due to salt freezing. • For the prototypical 0.2 MW reactor considered in this study considerable freezing occurs after 20 minutes leading to reactor temperatures above 900 °C within 4 hours. • Conservative criteria for the most important/least known variables in the design of DRACS have been discussed. • Over-conservative approaches in designing the NDHX should be used with caution as they can promote pipe clogging due to freezing. - Abstract: The possibility of molten-salt freezing in pipe-flow systems is a key concern for the solar-energy industry and a safety issue in the new generation of molten-salt reactors, worthy of careful consideration. This paper tackles the problem of coolant solidification in complex pipe networks by developing a transient thermohydraulic model and applying it to the ‘Direct Reactor Auxiliary Cooling System’ (DRACS), the passive-safety system proposed for the Generation-IV molten-salt reactors. The results indicate that DRACS, as currently envisioned, is prone to failure due to freezing in the air/molten-salt heat exchanger, which can occur after approximately 20 minutes, leading to reactor temperatures above 900 °C within 4 hours. The occurrence of this scenario is related to an unstable behaviour mode of DRACS in which newly formed solid-salt deposit on the pipe walls acts to decrease the flow-rate in the secondary loop, facilitating additional solid-salt deposition. Conservative criteria are suggested to facilitate preliminary assessments of early-stage DRACS designs. The present study is, to the knowledge of the authors, the first of its kind in serving to illustrate possible safety concerns in molten-salt reactors, which are otherwise considered very safe in the literature. Furthermore

Terahertz reflection spectroscopy of aqueous NaCl and LiCl solutions

DEFF Research Database (Denmark)

Jepsen, Peter Uhd; Merbold, Hannes

2010-01-01

frequencies. Whereas both the real and imaginary part of the permittivity of NaCl increases with concentration,we see that the imaginary part of the permittivity of LiCl (related to the absorption)decreases with increasing salt concentration. We relate these changes to the behavior...

The electrical conductivity of model melts based on LiCl-KCl, used for the processing of spent nuclear fuel

International Nuclear Information System (INIS)

Salyulev, Alexander; Potapov, Alexei; Khokhlov, Vladimir; Shishkin, Vladimir

2017-01-01

During pyrochemical reprocessing of spent nuclear fuel, complex melts based on LiCl-KCl eutectic are formed, but their properties are still not well studied. We measured the electrical conductivity of (LiCl-KCl) eut. − CeCl 3 , (LiCl-KCl) eut. − NdCl 3 and (LiCl-KCl) eut. − UCl 3 quasi-binary melts was up to 40 mol.% CeCl 3 , 40 mol.% NdCl 3 and 10.45 mol.% UCl 3 in a wide temperature span. In addition the electrical conductivity of several compositions, such as (LiCl-KCl) eut. − CeCl 3 + NdCl 3 and (LiCl-KCl) eut. − CeCl 3 + NdCl 3 + UCl 3 was measured. The measurements were carried out in quartz cells of the capillary type. When the total concentration of trivalent ions is less than 12 mol.%, we found that the conductivity of mixtures of arbitrary composition is almost a linear function of CeCl 3 , NdCl 3 , and UCl 3 the overall concentration.

Thermodynamics properties of plutonium in NaCl-KCl and CaCl2 at 1073 K and in liquid gallium

International Nuclear Information System (INIS)

Lambertin, D.; Ched'homme, S.; Bourges, G.; Pescayre, L.; Sanchez, S.; Picard, G.

2004-01-01

Cadmium and bismuth metal are mostly used as solvent in nuclear pyrochemical processes and especially in actinides/lanthanides separations. Gallium metal has been chosen because no literature values are available with plutonium and its regeneration by refining at low temperature is possible. Electrochemical window of gallium metal and activity coefficient of plutonium in gallium have been determined by using potentiometric method. Secondly, the electrochemical properties of plutonium have been studied in molten equimolar NaCl/KCl and CaCl 2 at 1073 K by cyclic voltammetry. The standard potentials of Pu(III)/Pu redox couple, respectively, -2,54 V and -2,51 V, led to the calculation of the activity coefficients of Pu(III). In CaCl 2 the complexation of Pu(III) ions is lower and the voltage gap between Pu(III)/Pu couple and the solvent limit is higher. The new data on plutonium electrochemistry in molten chlorides and liquid gallium media combined with literature data on lanthanides suggest that gallium can be a good solvent metal for pyro-chemistry separation. (authors)

The importance of SO{sub 2} and SO{sub 3} for sulphation of gaseous KCl - An experimental investigation in a biomass fired CFB boiler

Energy Technology Data Exchange (ETDEWEB)

Kassman, Haakan [Vattenfall Power Consultant AB, Nykoeping (Sweden); Chalmers University of Technology, Department of Energy and Environment, Division of Energy Technology, Gothenburg (Sweden); Baefver, Linda [Technical Research Institute of Sweden, Energy Technology, Boraas (Sweden); Aamand, Lars-Erik [Chalmers University of Technology, Department of Energy and Environment, Division of Energy Technology, Gothenburg (Sweden)

2010-09-15

This paper is based on results obtained during co-combustion of wood pellets and straw in a 12 MW circulating fluidised bed (CFB) boiler. Elemental sulphur (S) and ammonium sulphate ((NH{sub 4}){sub 2}SO{sub 4}) were used as additives to convert the alkali chlorides (mainly KCl) to less corrosive alkali sulphates. Their performance was then evaluated using several measurement tools including, IACM (on-line measurements of gaseous alkali chlorides), a low-pressure impactor (particle size distribution and chemical composition of extracted fly ash particles), and deposit probes (chemical composition in deposits collected). The importance of the presence of either SO{sub 2} or SO{sub 3} for gas phase sulphation of KCl is also discussed. Ammonium sulphate performed significantly better than elemental sulphur. A more efficient sulphation of gaseous KCl was achieved with (NH{sub 4}){sub 2}SO{sub 4} even when the S/Cl molar ratio was less than half compared to sulphur. Thus the presence of gaseous SO{sub 3} is of greater importance than that of SO{sub 2} for the sulphation of gaseous KCl. (author)

Influence of partial replacement of NaCl with KCl on profiles of volatile compounds in dry-cured bacon during processing.

Science.gov (United States)

Wu, Haizhou; Zhuang, Hong; Zhang, Yingyang; Tang, Jing; Yu, Xiang; Long, Men; Wang, Jiamei; Zhang, Jianhao

2015-04-01

This study investigated the influence of partial substitution of NaCl with KCl on the formation of volatile compounds in bacons during processing using a purge and trap dynamic headspace GC/MS system. Three substitutions were 0% KCl (I), 40% KCl (II), and 70% KCl (III). The profiles of the volatile compounds significantly changed during processing, particularly during the drying/ripening. At the end of process, the bacons from substitution III formed significantly higher levels of lipid-derived volatiles, such as straight chain aldehydes, hydrocarbons than bacons from substitution I and II, whereas the latter formed higher levels of volatiles from amino acid degradation such as 3-methylbutanal. There were very few differences in volatile formation between 0% and 40% KCl application. These results suggest that K(+) substitution of Na(+) by more than 40% may significantly change profiles of volatiles in finished dry-cured bacons and therefore would result in changes in the product aroma and/or flavour. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of chemical technology in nuclear fuel cycle

International Nuclear Information System (INIS)

Kim, Won Ho; Kim, J. S.; Kim, J. G.

2004-04-01

The objectives of this study are to develop the technology for both chemical analysis of fissile materials and fission products and chemical characterization in dry process, and also to compose LA/ICP-MS and micro-XRD systems. Chemical techniques for quantitative analysis of Cs, Tc, Np, Am, Cm in LiCl molten salts and Am, Cm, Tc, 3 H, 14 C in oxidized PWR spent fuel powders were developed for the evaluation of its material balance in the dry process. In particular, the rate of uranium oxide reduction was measured by the determination of concentrations of lithium metal and lithium oxide in LiCl molten salts. The solubility data of the reactants in LiCl molten salt were acquired, the oxide ion selective electrode to determine the oxide contents in the medium being fabricated, and a chronoamperometric technique applicable to in-line and real time monitoring of lithium metal reduction process was developed. On the other side, the electrochemical reduction of uranium oxides was studied, which has contributed to better understand the reduction behavior and thus lead to modify processes involved. Laser ablation ICP-MS system was developed by coupling laser ablation system with ICP-MS system, which was supposed to measure the isotope distribution from core to rim of irradiated fuel. The micro-XRD was developed with a micro beam, two hundreds times as narrow as conventional XRD, to measure structural changes of solid samples by 50μm interval in the radial direction. The performance of the two systems developed was confirmed by means of the examinations on precision, spatial resolution, and reproducibility. The development of LA/ICP-MS and micro-XRD system led to an establishment of techniques for the evaluation of its long-term integrity of high burn-up spent nuclear fuel and these techniques will be applied to the development of new nuclear fuels. Especially, the micro-XRD system will be useful to develop new materials and to control the quality in the various industrial

ESR studies of electron irradiated K3Ir(CN)6 in KCl single crystals

International Nuclear Information System (INIS)

Vugman, N.V.; Pinhal, N.M.

1983-01-01

ESR studies of KCl single crystals doped with small amounts of K 3 Ir(CN) 6 and submitted to a prolongued 2 MeV electron irradiation at room temperature reveal the presence of the [IR(CN) 5 Cl] 4- and [Ir(CN) 4 Cl 2 ] 4- new molecular species. Ligand spin densities and ligand field parameters are calculated from the experimental hyperfine and superhyperfine interactions and compared to previous data on the [Ir(CN) 5 ] 4- species. (Author) [pt

Thermodynamics properties of plutonium in NaCl-KCl and CaCl{sub 2} at 1073 K and in liquid gallium

Energy Technology Data Exchange (ETDEWEB)

Lambertin, D.; Ched' homme, S.; Bourges, G.; Pescayre, L.; Sanchez, S.; Picard, G

2004-07-01

Cadmium and bismuth metal are mostly used as solvent in nuclear pyrochemical processes and especially in actinides/lanthanides separations. Gallium metal has been chosen because no literature values are available with plutonium and its regeneration by refining at low temperature is possible. Electrochemical window of gallium metal and activity coefficient of plutonium in gallium have been determined by using potentiometric method. Secondly, the electrochemical properties of plutonium have been studied in molten equimolar NaCl/KCl and CaCl{sub 2} at 1073 K by cyclic voltammetry. The standard potentials of Pu(III)/Pu redox couple, respectively, -2,54 V and -2,51 V, led to the calculation of the activity coefficients of Pu(III). In CaCl{sub 2} the complexation of Pu(III) ions is lower and the voltage gap between Pu(III)/Pu couple and the solvent limit is higher. The new data on plutonium electrochemistry in molten chlorides and liquid gallium media combined with literature data on lanthanides suggest that gallium can be a good solvent metal for pyro-chemistry separation. (authors)

Sythesis of rare earth metal - GIC graphite intercalation compound in molten chloride system

International Nuclear Information System (INIS)

Ito, Masafumi; Hagiwara, Rika; Ito, Yasuhiko

1994-01-01

Graphite intercalation compounds of ytterbium and neodymium have been prepared by interacting graphite and metals in molten chlorides. These rare earth metals can be suspended in molten chlorides in the presence of trichlorides via disproportionation reaction RE(0) + RE(III) = 2RE(II) at lower than 300 degC. Carbides-free compounds are obtained in these systems. (author)

Advanced Thermal Storage System with Novel Molten Salt: December 8, 2011 - April 30, 2013

Energy Technology Data Exchange (ETDEWEB)

Jonemann, M.

2013-05-01

Final technical progress report of Halotechnics Subcontract No. NEU-2-11979-01. Halotechnics has demonstrated an advanced thermal energy storage system with a novel molten salt operating at 700 degrees C. The molten salt and storage system will enable the use of advanced power cycles such as supercritical steam and supercritical carbon dioxide in next generation CSP plants. The salt consists of low cost, earth abundant materials.

Preparation of tungsten coatings on graphite by electro-deposition via Na2WO4–WO3 molten salt system

International Nuclear Information System (INIS)

Sun, Ning-bo; Zhang, Ying-chun; Jiang, Fan; Lang, Shao-ting; Xia, Min

2014-01-01

Highlights: • Tungsten coatings on graphite were firstly obtained by electro-deposition method via Na 2 WO 4 –WO 3 molten salt system. • Uniform and dense tungsten coatings could be easily prepared in each face of the sample, especially the complex components. • The obtained tungsten coatings are with high purity, ultra-low oxygen content (about 0.022 wt%). • Modulate pulse parameters can get tungsten coatings with different thickness and hardness. - Abstract: Tungsten coating on graphite substrate is one of the most promising candidate materials as the ITER plasma facing components. In this paper, tungsten coatings on graphite substrates were fabricated by electro-deposition from Na 2 WO 4 –WO 3 molten salt system at 1173 K in atmosphere. Tungsten coatings with no impurities were successfully deposited on graphite substrates under various pulsed current densities in an hour. By increasing the current density from 60 mA cm −2 to 120 mA cm −2 an increase of the average size of tungsten grains, the thickness and the hardness of tungsten coatings occurs. The average size of tungsten grains can reach 7.13 μm, the thickness of tungsten coating was in the range of 28.8–51 μm, and the hardness of coating was higher than 400 HV. No cracks or voids were observed between tungsten coating and graphite substrate. The oxygen content of tungsten coating is about 0.022 wt%

The taste of KCl - What a difference a sugar makes.

Science.gov (United States)

Ben Abu, Natalie; Harries, Daniel; Voet, Hillary; Niv, Masha Y

2018-07-30

Dramatic increase in NaCl consumption lead to sodium intake beyond health guidelines. KCl substitution helps reduce sodium intake but results in a bitter-metallic off-taste. Two disaccharides, trehalose and sucrose, were tested in order to untangle the chemical (increase in effective concentration of KCl due to sugar addition) from the sensory effects. The bitter-metallic taste of KCl was reduced by these sugars, while saltiness was enhanced or unaltered. The perceived sweetness of sugar, regardless of its type and concentration, was an important factor in KCl taste modulation. Though KCl was previously shown to increase the chemical activity of trehalose but not of sucrose, we found that it suppressed the perceived sweetness of both sugars. Therefore, sensory integration was the dominant factor in the tested KCl-sugar combinations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Synthesis of hollandite-type LixMnO2 by Li+ ion-exchange in molten salt and lithium insertion characteristics

International Nuclear Information System (INIS)

Kadoma, Yoshihiro; Oshitari, Satoru; Ui, Koichi; Kumagai, Naoaki

2007-01-01

The Li + ion-exchange reaction of K + -type α-K 0.14 MnO 1.93 .nH 2 O containing different amounts of water molecules (n = 0-0.15) with a large (2 x 2) tunnel structure has been investigated in a LiNO 3 -LiCl molten salt at 300 deg. C. The Li + ion-exchanged products were examined by chemical analysis, X-ray diffraction, and transmission electron microscopy measurements. The K + ions and the hydrogens of the water molecules in the (2 x 2) tunnels of α-MnO 2 were exchanged by Li + ions in the molten salt, resulting in the Li + -type α-MnO 2 containing different amounts of Li + ions and lithium oxide (Li 2 O) in the (2 x 2) tunnels with maintaining the original hollandite structure. The electrochemical properties and structural variation with initial discharge and charge-discharge cycling of the Li + ion-exchanged α-MnO 2 samples have been investigated as insertion compounds in the search for new cathode materials for rechargeable lithium batteries. The Li + ion-exchanged α-MnO 2 samples provided higher capacities and higher Li + ion diffusivity than the parent K + -type materials on initial discharge and charge-discharge cyclings, probably due to the structural stabilization with the existence of Li 2 O in the (2 x 2) tunnels

Treatment of plutonium process residues by molten salt oxidation

Energy Technology Data Exchange (ETDEWEB)

Stimmel, J.; Wishau, R.; Ramsey, K.B.; Montoya, A.; Brock, J. [Los Alamos National Lab., NM (United States); Heslop, M. [Naval Surface Warfare Center (United States). Indian Head Div.; Wernly, K. [Molten Salt Oxidation Corp. (United States)

1999-04-01

Molten Salt Oxidation (MSO) is a thermal process that can remove more than 99.999% of the organic matrix from combustible {sup 238}Pu material. Plutonium processing residues are injected into a molten salt bed with an excess of air. The salt (sodium carbonate) functions as a catalyst for the conversion of the organic material to carbon dioxide and water. Reactive species such as fluorine, chlorine, bromine, iodine, sulfur, phosphorous and arsenic in the organic waste react with the molten salt to form the corresponding neutralized salts, NaF, NaCl, NaBr, NaI, Na{sub 2}SO{sub 4}, Na{sub 3}PO{sub 4} and NaAsO{sub 2} or Na{sub 3}AsO4. Plutonium and other metals react with the molten salt and air to form metal salts or oxides. Saturated salt will be recycled and aqueous chemical separation will be used to recover the {sup 238}Pu. The Los Alamos National Laboratory system, which is currently in the conceptual design stage, will be scaled down from current systems for use inside a glovebox.

Treatment of plutonium process residues by molten salt oxidation

International Nuclear Information System (INIS)

Stimmel, J.; Wishau, R.; Ramsey, K.B.; Montoya, A.; Brock, J.; Heslop, M.

1999-01-01

Molten Salt Oxidation (MSO) is a thermal process that can remove more than 99.999% of the organic matrix from combustible 238 Pu material. Plutonium processing residues are injected into a molten salt bed with an excess of air. The salt (sodium carbonate) functions as a catalyst for the conversion of the organic material to carbon dioxide and water. Reactive species such as fluorine, chlorine, bromine, iodine, sulfur, phosphorous and arsenic in the organic waste react with the molten salt to form the corresponding neutralized salts, NaF, NaCl, NaBr, NaI, Na 2 SO 4 , Na 3 PO 4 and NaAsO 2 or Na 3 AsO4. Plutonium and other metals react with the molten salt and air to form metal salts or oxides. Saturated salt will be recycled and aqueous chemical separation will be used to recover the 238 Pu. The Los Alamos National Laboratory system, which is currently in the conceptual design stage, will be scaled down from current systems for use inside a glovebox

An optimized symbiotic fusion and molten-salt fission reactor system

International Nuclear Information System (INIS)

Blinkin, V.L.; Novikov, V.M.

A symbiotic fusion-fission reactor system which breeds nuclear fuel is discussed. In the blanket of the controlled thermonuclear reactor (CTR) uranium-233 is generated from thorium, which circulates in the form of ThF 4 mixed with molten sodium and beryllium fluorides. The molten-salt fission reactor (MSR) burns up the uranium-233 and generates tritium for the fusion reactor from lithium, which circulates in the form of LiF mixed with BeF 2 and 233 UF 4 through the MSR core. With a CTR-MSR thermal power ratio of 1:11 the system can produce electrical energy and breed fuel with a doubling time of 4-5 years. The system has the following special features: (1) Fuel reprocessing is much simpler and cheaper than for contemporary fission reactors; reprocessing consists simply in continuous removal of 233 U from the salt circulating in the CTR blanket by the fluorination method and removal of xenon from the MSR fuel salt by gas scavenging; the MSR fuel salt is periodically exchanged for fresh salt and the 233 U is then removed from it; (2) Tritium is produced in the fission reactor, which is a much simpler system than the fusion reactor; (3) The CTR blanket is almost ''clean''; no tritium is produced in it and fission fragment activity does not exceed the activity induced in the structural materials; (4) Almost all the thorium introduced into the CTR blanket can be used for producing 233 U

Time-of-flight pulsed neutron diffraction of molten salts

Energy Technology Data Exchange (ETDEWEB)

Fukushima, Y; Misawa, M; Suzuki, K [Tohoku Univ., Sendai (Japan). Research Inst. for Iron, Steel and Other Metals

1975-06-01

In this work, the pulsed neutron diffraction of molten alkali metal nitrate and bismuth trihalide was measured by the time-of-flight method. An electron linear accelerator was used as the pulsed neutron source. All the measurements were carried out with the T-O-F neutron diffractometer installed on the 300 MeV electron lineac. Molten NaNO/sub 3/ and RbNO/sub 3/ were adopted as the samples for alkali metal nitrate. The measurement is in progress for KNO/sub 3/ and LiNO/sub 3/. As the first step of the study on bismuth-bismuth trihalide system, the temperature dependence of structure factors was observed for BiCl/sub 3/, BiBr/sub 3/ and BiI/sub 3/ in the liquid state. The structure factors Sm(Q) for molten NaNO/sub 3/ at 340/sup 0/C and RbNO/sub 3/ at 350/sup 0/C were obtained, and the form factor F/sub 1/(Q) for single NO/sub 3//sup -/ radical with equilateral triangle structure was calculated. In case of molten NaNO/sub 3/, the first peak of Sm(Q) is simply smooth and a small hump can be observed in the neighbourhood of the first minimum Q position. The first peak of Sm(Q) for molten RbNO/sub 3/ is divided into two peaks, whereas a hump at the first minimum becomes big, and shifts to the low Q side of the second peak. The size of the NO/sub 3//sup -/ radical in molten NaNO/sub 3/ is a little smaller than that in molten RbNO/sub 3/. The values of the bond length in the NO/sub 3//sup -/ radical are summarized for crystal state and liquid state. The temperature dependence of the structure factor S(Q) was observed for BiCl/sub 3/, BiBr/sub 3/ and BiI/sub 3/, and shown in a figure.

HTGR molten salt sensible energy transmission and storage system design and costs

International Nuclear Information System (INIS)

1981-09-01

This report, which was prepared for Gas-Cooled Reactor Associates by United Engineers and Constructors under Contract No. GCRA/UE and C 81-203, presents the design and cost for a molten salt Sensible Energy Transmission and Storage (SETS) System. Although the reference system for this study is sized to be compatible with an 1170 MW(t) HTGR Nuclear Heat Source, the results and conclusions should be generally applicable to most large scale molten salt energy transmission system applications. A preliminary conceptual design is presented and alternative configurations are discussed. The sensitivity of system costs to variations in important system parameters are also presented. Costs for a reference case conceptual design are reported in constant 1980 dollars and inflated 1995 dollars

New primary energy source by thorium molten-salt reactor technology

International Nuclear Information System (INIS)

Furukawa, Kazuo; Kato, Yoshio; Furuhashi, Akira; Numata, Hiroo; Mitachi, Koushi; Yoshioka, Ritsuo; Sato, Yuzuru; Arakawa, Kazuto

2005-01-01

Among the next 30 years, we have to implement a practical measure in the global energy/environmental problems, solving the followings: (1) replacing the fossil fuels without CO 2 emission, (2) no severe accidents, (3) no concern on military, (4) minimizing wastes, (5) economical, (6) few R and D investment and (7) rapid/huge global application supplying about half of the total primary energy till 50 years later. For this purpose the following system was proposed: THORIMS-NES [Thorium Molten-Salt Nuclear Energy Synergetic System], which is composed of (A) simple fission Molten-Salt power stations (FUJI), and (B) fissile-producing Accelerator Molten-Salt Breeder (AMSB). It has been internationally prepared a practical Developmental Program for its huge-size industrialization of Th breeding fuel cycle to produce a new rational primary energy. Here it is explained the social meaning, the conceptual system design and technological bases, especially, including the molten fluoride salt technology, which was developed as the triple-functional medium for nuclear-engineering, heat-transfer and chemical engineering. The complex function of this system is fully achieved by the simplified facility using a single phase molten-salt only. (author)

Pourbaix diagrams of actinides in molten chlorides using an indicating electrode for oxide ion activity

International Nuclear Information System (INIS)

Lambertin, D.; Lacquement, J.

2000-01-01

Pyrochemical separation methods using high temperature molten salt media could emerge as promising and valuable routes compared with aqueous methods for separation and transmutation strategies for long-lived radionuclides. A good knowledge of the molten salt chemistry is essential for controlling these separations, and elementary data are required for molten halide salts, which can be readily provided by electrochemical methods. Applying the chemical principles of aqueous solutions to the molten salt media, Pourbaix diagrams - called in this case potential-oxo-acidity (pO 2- ) - can be plotted. They offer a rapid and comprehensive view of the thermodynamic properties of selected elements in a solvent of interest. Two methods are available for preparing these diagrams. The first is based on available thermodynamic data on pure element oxide (and oxychloride) compounds and on element chloride activity coefficients in melt (which can be electrochemically determined). In this method, we consider the oxide anion exchange reactions between the pure compounds, water and hydrogen chloride. The second method is a direct and experimental determination of the oxo-acidic properties of the studied element chlorides in melts. Use of an Yttria-Stabilised Zirconia Membrane (YSZM) electrode (oxide anion selective electrode) helps determine the nature of the stable oxide compounds in melts as well as their stabilities. The YSZM is used with a silver/silver chloride reference system, and was developed 25 years ago. Two examples of Potential-acidity diagrams. Employing the first method and the determination of the standard potential of plutonium in LiCl-KCl and NaCl-KCl eutectic mixtures, potential-oxo-acidity diagrams were plotted for these melts at various temperatures. It was found that the stability domain for plutonium chloride depends on the melt composition (influence of oxide anion solvation). We also used the Omega acidity function - based on reaction (1) - which is a

Successful Management of Tubal Ectopic Pregnancy with Transvaginal Sonography Guided Intracardiac KCL Injection and Systemic Methotrexate - A Case Report

Directory of Open Access Journals (Sweden)

Sumesh Choudhary

2014-01-01

Full Text Available Background: Methotrexate (Mtx is an accepted modality for conservative treatment of ectopic pregnancy. However, there is no consensus regarding its use in live ectopic pregnancy and high serum beta-human chorionic gonadotrophin (β-hCG titres. Concurrent use of intra-sac hypertonic KCl, to produce cardiac asystole with systemic Mtx potentially improve outcome in live ectopic gestations with very high serum β-hCG titres. Here a successful management of live ectopic pregnancy in a 25-year-old nulliparous woman, with very high β-hCG titres (29502.04mIU/mL, using ultrasound-guided intra-cardiac potassium chloride (KCl injection and systemic Mtx is reported. No treatment related complications were encountered. However, individualized treatment with a stringent follow-up regime is mandatory in such cases.

Quaternary reciprocal system Na,K//Cl,Co3,MoO4

International Nuclear Information System (INIS)

Kochkarov, Zh.A.; Gasanaliev, A.M.

2004-01-01

Quaternary reciprocal system Na,K//Cl,Co 3 ,MoO 4 has been investigated for the first time by differential thermal analysis using the methods of projective and differential geometry. A stable (KCl) 2 -Na 2 CO 3 -K 2 CO 3 -K 2 MoO 4 tetrahedron and (NaCl) 2 -(KCl) 2 -Na 2 CO 3 -K 2 MoO 4 -Na 2 MoO 4 pentatope have been revealed in the system. It has been found that four quadruple invariant points are realized in the Na,K//Cl,Co 3 ,MoO 4 system, including one eutectic and three peritectic points [ru

Thermochemical properties of media for pyrometallurgical nuclear fuel reprocessing

International Nuclear Information System (INIS)

Hosoya, Yuji; Terai, Takayuki

1998-01-01

Molten chloride/cadmium system is considered to be applied to a solvent in pyrochemical reprocessing of spent nuclear fuel. In this work, phase diagrams for molten chloride systems were constructed, using NdCl 3 as an imitative substance in place of UCl 3 or PuCl 3 . Hastelloy-X (Ni/Cr21/Fe18/Mo9/W) was examined as a structural material for the corrosion-resistance against molten chloride baths containing NdCl 3 . The process of corrosion was thermochemically discussed and the form of the corrosion was illustrated. Rutherford backscattering spectroscopy was successfully applied to determine the elemental distribution profile of specimens tested on the compatibility with molten chloride mixture at elevated temperature. Ferritic steel was also examined as another candidate material for the compatibility with molten cadmium covered with LiCl-KCl eutectic salt. Variation of near-surface composition was observed by comparing the results of Rutherford backscattering spectroscopy obtained before and after the dipping. (author)

Molten Triazolium Chloride Systems as New Aluminum Battery Electrolytes

DEFF Research Database (Denmark)

Vestergaard, B.; Bjerrum, Niels; Petrushina, Irina

1993-01-01

-170-degrees-C) depending on melt acidity and anode material. DMTC, being specifically adsorbed and reduced on the tungsten electrode surface, had an inhibiting effect on the aluminum reduction, but this effect was suppressed on the aluminum substrate. An electrochemical process with high current density (tens...... of milliamperes per square centimeter) was observed at 0.344 V on the acidic sodium tetrachloroaluminate background, involving a free triazolium radical mechanism. Molten DMTC-AlCl3 electrolytes are acceptable for battery performance and both the aluminum anode and the triazolium electrolyte can be used as active......The possibility of using molten mixtures of 1,4-dimethyl-1,2,4-triazolium chloride (DMTC) and aluminum chloride (AlCl3) as secondary battery electrolytes was studied, in some cases extended by the copresence of sodium chloride. DMTC-AlCl, mixtures demonstrated high specific conductivity in a wide...

Rheed Investigation of Pd/Al Bimetallic System on KCl(001) Substrate

Science.gov (United States)

Masek, K.; Moroz, V.; Matolín, V.

Pd/Al alloys have very interesting properties from the point of view of their possible application in heterogeneous catalysis. Preparation of small heteroepitaxial Pd/Al alloy particles opens a new way in studies of the influence of Pd/Al crystallographic structure on the alloy catalytic properties. Pd/Al alloy particles were grown by the molecular beam epitaxy method. Their crystallographical structure was controlled by reflection high energy electron diffraction (RHEED). It was found that Pd deposited on epitaxial 3D Al particles grown on KCl is intermixing with Al. This process is accompanied by the variation of lattice parameter from the Al value to the Pd one.

Preparing of LiCl-KCl-UCl3 eutectic salt by a chlorination of Cd

International Nuclear Information System (INIS)

Kang, Hee Seok; Woo, Moon Sik; Lee, Han Soo

2008-01-01

Uranium trichloride salt(UCl 3 ) is supplied with the initial U in to the LiCl-KCl eutectic salt for a stabilization of the initial cell voltage during an electrorefining process in a reactor. The apparatus for producing UCl 3 consists of a chlorine gas generator, a chlorinator, and an off-gas wet scrubber. Gaseous chlorine in the chlorine gas generator was injected into a lower layer of liquid Cd where CdCl 2 formed. The CdCl 2 reacts with the uranium to form uranium trichloride and Cd. The throughput of the UCl 3 chlorinator is about. 1.4Kg UCl 3 /batch. During a production the temperature of the reactants are maintained at about 600 .deg. C

Preparation and melting of uranium from U3O8

International Nuclear Information System (INIS)

Hur, Jin-Mok; Choi, In-Kyu; Cho, Soo-Haeng; Jeong, Sang-Mun; Seo, Chung-Seok

2008-01-01

In this paper, we report on the preparation and melting of uranium in association with a spent nuclear fuel conditioning process. U 3 O 8 powder was electrochemically reduced in a mixture of molten LiCl-Li 2 O (∼3 wt.% of Li 2 O in LiCl) at 650 deg. C resulting in the formation of uranium and Li 2 O with a yield of >99%. When the powder of uranium with a residual LiCl-Li 2 O salt was heated in order to melt the metal, the uranium oxidation to UO 2 due to the reaction with Li 2 O was observed. We were able to synthesize FeU 6 by using a Fe based cathode during the U 3 O 8 reduction procedure. FeU 6 could be melted to below the temperatures where the oxidation of uranium by Li 2 O occurred. The idea of compound formation and melting is applicable to the melting and casting of a spent nuclear fuel which contains oxidative residual salts due to its conditioning in a molten salt

Structure and thermodynamics of molten salts

International Nuclear Information System (INIS)

Papatheodorou, G.N.

1983-01-01

This chapter investigates single-component molten salts and multicomponent salt mixtures. Molten salts provide an important testing ground for theories of liquids, solutions, and plasmas. Topics considered include molten salts as liquids (the pair potential, the radial distribution function, methods of characterization), single salts (structure, thermodynamic correlations), and salt mixtures (the thermodynamics of mixing; spectroscopy and structure). Neutron and X-ray scattering techniques are used to determine the structure of molten metal halide salts. The corresponding-states theory is used to obtain thermodynamic correlations on single salts. Structural information on salt mixtures is obtained by using vibrational (Raman) and electronic absorption spectroscopy. Charge-symmetrical systems and charge-unsymmetrical systems are used to examine the thermodynamics of salt mixtures

Dry separation technology of transuranic elements

International Nuclear Information System (INIS)

Inoue, Tadashi

1999-01-01

The separation principle of transuranic elements (TRU) by a dry method, the separation technique of TRU from a high level waste solution and a dry recycle technology of LWR and FBR fuel cycle are explained. The dry method used molten salt and liquid metal. TRU and the rare earth elements in the molten salt (LiCl-KCl, LiCl-KCl/Cd and LiCl-KCl/Bi system) were separated by two methods such as the electrolytic refining and the reduction-extraction method. The former method separated 98% U, Np and Pu, but low Am. The latter method was able to separate more than 99.9% Np and Pu and 99.7% Am. (S.Y.)

Development of High Temperature Transport System for Molten Salt

International Nuclear Information System (INIS)

Lee, S. H.; Lee, H. S.; Kim, J. G.

2011-01-01

Pyroprocessing technology is one of the the most promising technologies for the advanced fuel cycle with favorable economic potential and intrinsic proliferation-resistance. The electrorefining process, one of main processes which is composed of pyroprocess to recover the useful elements from spent fuel, is under development at the Korea Atomic Energy Research Institute as a sub process of the pyrochemical treatment of spent PWR fuel. High-temperature molten salt transport technologies are required because a molten salt should be transported from the electrorefiner to electrowiner after the electrorefining process. Therefore, in pyrometallurgical processing, the development of high-temperature molten salt transport technologies is a crucial prerequisite. However, there have been a few transport studies on high-temperature molten salt. In this study, an apparatus for suction transport experiments was designed and constructed for the development of high temperature transport technology for molten salt, and the performance test of the apparatus was performed. And also, predissolution test of the salt was carried out using the reactor with furnace in experimental apparatus

Lithium isotope effect during solvent extraction of LiCl with isoamyl alcohol

International Nuclear Information System (INIS)

Levkin, A.V.; Zhilov, V.I.; Marokin, O.V.; Demin, S.V.

1991-01-01

Method of extraction chromatography was used to measure the coefficient of lithium isotope separation (α) during extraction with isoamyl alcohol from concentrated LiCl aqueous solution. The α value is equal to 1.0036±0.0009; heavy 7 Li isotope is concentrated in organic phase at that

Electrochemical formation of uranium-zirconium alloy in LiCl-KCl melts

Energy Technology Data Exchange (ETDEWEB)

Murakami, Tsuyoshi, E-mail: m-tsuyo@criepi.denken.or.j [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Kato, Tetsuya; Kurata, Masaki [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Yamana, Hajimu [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)

2009-11-15

Since zirconium is considered an electrochemically active species under practical conditions of the electrorefining process, it is crucial to understand the electrochemical behavior of zirconium in LiCl-KCl melts containing actinide ions. In this study, the electrochemical codeposition of uranium and zirconium on a solid cathode was performed. It was found that the delta-(U, Zr) phase, which is the only intermediate phase of the uranium-zirconium binary alloy system, was deposited on a tantalum substrate by potentiostatic electrolysis at -1.60 V (vs. Ag{sup +}/Ag) in LiCl-KCl melts containing 0.13 in mol% UCl{sub 3} and 0.23 in mol% ZrCl{sub 4} at 773 K. To our knowledge, this is the first report on the electrochemical formation of the delta-(U, Zr) phase. The relative partial molar properties of uranium in the delta-(U, Zr) phase were evaluated by measuring the open-circuit-potentials of the electrochemically prepared delta-phase electrode.

Electrochemical formation of uranium-zirconium alloy in LiCl-KCl melts

International Nuclear Information System (INIS)

Murakami, Tsuyoshi; Kato, Tetsuya; Kurata, Masaki; Yamana, Hajimu

2009-01-01

Since zirconium is considered an electrochemically active species under practical conditions of the electrorefining process, it is crucial to understand the electrochemical behavior of zirconium in LiCl-KCl melts containing actinide ions. In this study, the electrochemical codeposition of uranium and zirconium on a solid cathode was performed. It was found that the δ-(U, Zr) phase, which is the only intermediate phase of the uranium-zirconium binary alloy system, was deposited on a tantalum substrate by potentiostatic electrolysis at -1.60 V (vs. Ag + /Ag) in LiCl-KCl melts containing 0.13 in mol% UCl 3 and 0.23 in mol% ZrCl 4 at 773 K. To our knowledge, this is the first report on the electrochemical formation of the δ-(U, Zr) phase. The relative partial molar properties of uranium in the δ-(U, Zr) phase were evaluated by measuring the open-circuit-potentials of the electrochemically prepared δ-phase electrode.

Compatibility tests between molten salts and metal materials (2)

International Nuclear Information System (INIS)

Shiina, Yasuaki

2003-08-01

Latent heat storage technology using molten salts can reduce temperature fluctuations of heat transfer fluid by latent heat for middle and high temperature regions. This enables us to operate several heat utilization systems in cascade connected to High Temperature Gas Cooled Reactors (HTGRs) from high to low temperature range by setting the latent heat storage system after a heat utilization system to reduce thermal load after the heat utilization systems. This latent heat technology is expected to be used for effective use of heat such as equalization of electric load between night and daytime. In the application of the latent heat technology, compatibility between molten salts and metal materials is very important because molten salts are corrosive, and heat transfer pipes and vessels will contact with the molten salts. It will be necessary to prevail the latent heat storage technique that normal metal materials can be used for the pipes and vessels. However, a few studies have been reported of compatibility between molten salts and metals in middle and high temperature ranges. In this study, four molten salts, range of the melting temperature from 490degC to 800degC, are selected and five metals, high temperature and corrosion resistance steels of Alloy600, HastelloyB2, HastelloyC276, SUS310S and pure Nickel are selected for the test with the consideration of metal composition. Test was performed in an electric furnace by setting the molten salts and the metals in melting pots in an atmosphere of nitrogen. Results revealed excellent corrosion resistance of pure Nickel and comparatively low corrosion resistance of nickel base alloys such as Alloy600 and Hastelloys against Li 2 CO 3 . Corrosion resistance of SUS310S was about same as nickel based alloys. Therefore, if some amount of corrosion is permitted, SUS310S would be one of the candidate alloys for structure materials. These results will be used as reference data to select metals in latent heat technology

Development of fuel cycle technology for molten-salt reactor systems

International Nuclear Information System (INIS)

Uhlir, J.

2006-01-01

Full text: Full text: The Molten-Salt Reactor (MSR) represents one of promising advanced reactor type assigned to the GEN IV reactor systems. It can be operated either as thorium breeder within the Th -133U fuel cycle or as actinide transmuter incinerating transuranium fuel. Essentially the main advantage of MSR comes out from the prerequisite, that this reactor type should be directly connected with the 'on-line' reprocessing of circulating liquid (molten-salt) fuel. This principle should allow very effective extraction of freshly constituted fissile material (233U). Besides, the on-line fuel salt clean up is necessary within a long run to keep the reactor in operation. As a matter of principle, it permits to clear away typical reactor poisons like xenon, krypton, lanthanides etc. and possibly also other products of burned plutonium and transmuted minor actinides. The fuel salt clean up technology should be linked with the fresh MSR fuel processing to continuously refill the new fuel (thorium or transuranics) into the reactor system. On the other hand, the technologies of fresh transuranium molten-salt fuel processing from the current LWR spent fuel and of the on-line reprocessing of MSR fuel represent two killing points of the whole MSR technology, which have to be successfully solved before MSR deployment in the future. There are three main pyrochemical partitioning techniques proposed for processing and/or reprocessing of MSR fuel: Fluoride volatilization processes, Molten salt / liquid metal extraction processes and Electrochemical separation processes. Two of them - Fluoride Volatility Method and Electrochemical separation process from fluoride media are under development in the Nuclear Research Institute Rez pic. R and D in the field of Fluoride Volatility Method is concentrated to the development and verification of experimental semi-pilot technology for LWR spent fuel reprocessing, which may result in a product the form and composition of which might be

Physical properties of molten carbonate electrolyte

Energy Technology Data Exchange (ETDEWEB)

Kojima, T.; Yanagida, M.; Tanimoto, K. [Osaka National Research Institute (Japan)] [and others

1996-12-31

Recently many kinds of compositions of molten carbonate electrolyte have been applied to molten carbonate fuel cell in order to avoid the several problems such as corrosion of separator plate and NiO cathode dissolution. Many researchers recognize that the addition of alkaline earth (Ca, Sr, and Ba) carbonate to Li{sub 2}CO{sub 3}-Na{sub 2}CO{sub 3} and Li{sub 2}CO{sub 3}-K{sub 2}CO{sub 3} eutectic electrolytes is effective to avoid these problems. On the other hand, one of the corrosion products, CrO{sub 4}{sup 2-} ion is found to dissolve into electrolyte and accumulated during the long-term MCFC operations. This would affect the performance of MCFC. There, however, are little known data of physical properties of molten carbonate containing alkaline earth carbonates and CrO{sub 4}{sup 2-}. We report the measured and accumulated data for these molten carbonate of electrical conductivity and surface tension to select favorable composition of molten carbonate electrolytes.

IRSL characteristics of NaCl and KCl relative to dosimeter

International Nuclear Information System (INIS)

Tanir, Guenes; Hicabi Boeluekdemir, M.; Catli, Serap; Tel, Eyyuep

2007-01-01

The aim of this work is to determine and compare the dosimetric properties of NaCl and KCl samples using infrared-stimulated luminescence (IRSL) technique. For a material to be used as dosimeter, both the IRSL temperature dependence and the radiation dose response have critical importance. In this work the IRSL characteristics from NaCl and KCl samples were experimentally investigated as a function of temperature and laboratory radiation doses. Dosimetric properties of NaCl and KCl samples were found significantly different. The IRSL signals displayed by NaCl were found to be more stable, reliable and agreeable than those of KCl

Electrochemical separation of uranium in the molten system LiF-NaF-KF-UF4

Science.gov (United States)

Korenko, M.; Straka, M.; Szatmáry, L.; Ambrová, M.; Uhlíř, J.

2013-09-01

This article is focused on the electrochemical investigation (cyclic voltammetry and related studies) of possible reduction of U4+ ions to metal uranium in the molten system LiF-NaF-KF(eut.)-UF4 that can provide basis for the electrochemical extraction of uranium from molten salts. Two-step reduction mechanism for U4+ ions involving one electron exchange in soluble/soluble U4+/U3+ system and three electrons exchange in the second step were found on the nickel working electrode. Both steps were found to be reversible and diffusion controlled. Based on cyclic voltammetry, the diffusion coefficients of uranium ions at 530 °C were found to be D(U4+) = 1.64 × 10-5 cm2 s-1 and D(U3+) 1.76 × 10-5 cm2 s-1. Usage of the nickel spiral electrode for electrorefining of uranium showed fairly good feasibility of its extraction. However some oxidant present during the process of electrorefining caused that the solid deposits contained different uranium species such as UF3, UO2 and K3UO2F5.

Characterization of glial cell K-Cl cotransport.

Science.gov (United States)

Gagnon, Kenneth B E; Adragna, Norma C; Fyffe, Robert E W; Lauf, Peter K

2007-01-01

The molecular mechanism of K-Cl cotransport (KCC) consists of at least 4 isoforms, KCC 1, 2, 3, and 4 which, in multiple combinations, exist in most cells, including erythrocytes and neuronal cells. We utilized reverse-transcriptase-polymerase chain reaction (RT-PCR) and ion flux studies to characterize KCC activity in an immortalized in vitro cell model for fibrous astrocytes, the rat C6 glioblastoma cell. Isoform-specific sets of oligonucleotide primers were synthesized for NKCC1, KCC1, KCC2, KCC3, KCC4, and also for NKCC1 and actin. K-Cl cotransport activity was determined by measuring either the furosemide-sensitive, or the Cl(-)-dependent bumetanide-insensitive Rb(+) (a K(+) congener) influx in the presence of the Na/K pump inhibitor ouabain. Rb(+) influx was measured at a fixed external Cl concentrations, [Cl(-)](e), as a function of varying external Rb concentrations, [Rb(+)](e), and at a fixed [Rb(+)](e) as a function of varying [Cl(-)](e), and with equimolar Cl replacement by anions of the chaotropic series. RT-PCR of C6 glioblastoma (C6) cells identified mRNA for three KCC isoforms (1, 3, and 4). NKCC1 mRNA was also detected. The apparent K(m) for KCC-mediated Rb(+) influx was 15 mM [Rb(+)](e), and V(max) 12.5 nmol Rb(+) * mg protein(-1) * minute(-1). The calculated apparent K(m) for external Cl(-) was 13 mM and V(max) 14.4 nmol Rb(+) * mg protein(-1) * minute(-1). The anion selectivity sequence of the furosemide-sensitive Rb(+) influx was Cl(-)>Br-=NO(3)(-)>I(-)=SCN(-)>Sfm(-) (sulfamate). Established activators of K-Cl cotransport, hyposmotic shock and N-ethylmaleimide (NEM) pretreatment, stimulated furosemide-sensitive Rb(+) influx. A ñ50% NEM-induced loss of intracellular K(+) was prevented by furosemide. We have identified by RT-PCR the presence of three distinct KCC isoforms (1, 3, and 4) in rat C6 glioblastoma cells, and functionally characterized the anion selectivity and kinetics of their collective sodium-independent cation-chloride cotransport

Supercrystallization of KCl from solution irradiated by soft X-rays

Science.gov (United States)

Janavičius, A. J.; Rinkūnas, R.; Purlys, R.

2016-10-01

The X-rays influence on KCl crystallization in a saturated water solution has been investigated for the aim of comparing it with previously considered NaCl crystallization. The rate of crystallization has been measured in the drying drop in the solution activated by the irradiation. We have measured the influence of the irradiation time of the solution on the rates of KCl crystallization as well as the beginning of the crystallization processes on drying drops. For a longer irradiation time of the solution early crystallization in the drops occurs. A saturated water solution of KCl was irradiated with the diffractometer DRON-3M (Russian device) and this had a great influence on the two-step processes of crystallization. The ionization of the solution by soft X-rays can produce ions, metastable radicals in water, excited crystals' seeds and vacancies in growing crystals by Auger's effect. The X-rays generate a very fast crystallization in the drying drop.

Growth and time dependent alignment of KCl crystals in Hemoglobin LB monolayer

International Nuclear Information System (INIS)

Mahato, Mrityunjoy; Pal, Prabir; Tah, Bidisha; Kamilya, Tapanendu; Talapatra, G.B.

2012-01-01

Nature and organism often use the biomineralization technique to build up various highly regular structures such as bone, teeth, kidney stone etc., and recently this becomes the strategy to design and synthesis of novel biocomposite materials. We report here the controlled crystallization of KCl in Langmuir and Langmuir Blodgett (LB) monolayer of Hemoglobin (Hb) at ambient condition. The nucleation and growth of KCl crystals in Hb monolayer has temporal and KCl concentration dependency. The growth of KCl crystals in LB film of Hb has distinct behavior in the alignment of crystals from linear to fractal like structures depending on growth time. The crystallographic identity of the biomineralized KCl crystal is confirmed from HR-TEM, XRD, and from powder diffraction simulation. Our results substantiated that the template of Langmuir monolayer of proteins plays a crucial role in biomineralization as well as in designing and synthesizing of novel biocomposite materials. Highlights: ► Biomineralization of KCl crystal has been studied in Hemoglobin LB film. ► KCl crystal growth is time and concentration of KCl dependent. ► The alignment of KCl crystal growth is fractal nature with time. ► The unfolding of Hb and evaporation factor has some role in crystallization and fractal growth.

Structure of molten TbCl sub 3 measured by neutron diffraction

CERN Document Server

Martin, R A; Barnes, A C; Cuello, G J

2002-01-01

The total structure factor of molten TbCl sub 3 at 617 deg. C was measured by using neutron diffraction. The data are in agreement with results from previous experimental work but the use of a diffractometer having an extended reciprocal-space measurement window leads to improved resolution in real space. Significant discrepancies with the results obtained from recent molecular dynamics simulations carried out using a polarizable ion model, in which the interaction potentials were optimized to enhance agreement with previous diffraction data, are thereby highlighted. It is hence shown that there is considerable scope for the development of this model for TbCl sub 3 and for other trivalent metal halide systems spanning a wide range of ion size ratios. (letter to the editor)

Automatic Welding System of Aluminum Pipe by Monitoring Backside Image of Molten Pool Using Vision Sensor

Science.gov (United States)

Baskoro, Ario Sunar; Kabutomori, Masashi; Suga, Yasuo

An automatic welding system using Tungsten Inert Gas (TIG) welding with vision sensor for welding of aluminum pipe was constructed. This research studies the intelligent welding process of aluminum alloy pipe 6063S-T5 in fixed position and moving welding torch with the AC welding machine. The monitoring system consists of a vision sensor using a charge-coupled device (CCD) camera to monitor backside image of molten pool. The captured image was processed to recognize the edge of molten pool by image processing algorithm. Neural network model for welding speed control were constructed to perform the process automatically. From the experimental results it shows the effectiveness of the control system confirmed by good detection of molten pool and sound weld of experimental result.

Deficiency of electroneutral K+-Cl- cotransporter 3 causes a disruption in impulse propagation along peripheral nerves.

Science.gov (United States)

Sun, Yuan-Ting; Lin, Thy-Sheng; Tzeng, Shun-Fen; Delpire, Eric; Shen, Meng-Ru

2010-10-01

Nerve conduction requires the fine tuning of ionic currents through delicate interactions between axons and Schwann cells. The K(+)-Cl(-) cotransporter (KCC) family includes four isoforms (KCC1-4) that play an important role in the maintenance of cellular osmotic homeostasis via the coupled electroneutral movement of K(+) and Cl(-) with concurrent water flux. Mutation in SLC12A6 gene encoding KCC3 results in an autosomal recessive disease, known as agenesis of the corpus callosum associated with peripheral neuropathy. Nevertheless, the role of KCC3 in nerve function remains a puzzle. In this study, the microscopic examination of KCC isoforms expressed in peripheral nerves showed high expression of KCC2-4 in nodal segments of the axons and in the perinucleus and microvilli of Schwann cells. The KCC inhibitor [[(dihydroindenyl)oxy]alkanoic acid] but not the Na(+)-K(+)-2Cl(-)-cotransport inhibitor (bumetanide) dose-dependently suppressed the amplitude and area of compound muscle action potential, indicating the involvement of KCC activity in peripheral nerve conduction. Furthermore, the amplitude and area under the curve were smaller, and the nerve conduction velocity was slower in nerves from KCC3(-/-) mice than in nerves from wild-type mice, while the expression pattern of KCC2 and KCC4 was similar in KCC3 kockout and wild-type strains. KCC3(-/-) mice also manifested a prominent motor deficit in the beam-walking test. This is the first study to demonstrate that the K(+)-Cl(-) cotransporter activity of KCC3 contributes to the propagation of action potentials along peripheral nerves. (c) 2010 Wiley-Liss, Inc.

Temperature dependence of diffusion coefficients of trivalent uranium ions in chloride and chloride-fluoride melts

International Nuclear Information System (INIS)

Komarov, V.E.; Borodina, N.P.

1981-01-01

Diffusion coefficients of U 3+ ions are measured by chronopotentiometric method in chloride 3LiCl-2KCl and in mixed chloride fluoride 3LiCl(LiF)-2KCl melts in the temperature range 633-1235 K. It is shown It is shown that experimental values of diffusion-coefficients are approximated in a direct line in lg D-1/T coordinate in chloride melt in the whole temperature range and in chloride-fluoride melt in the range of 644-1040 K. Experimental values of diffusion coefficients diviate from Arrhenius equation in the direction of large values in chloride-fluoride melt at further increase of temperature up to 1235 K. Possible causes of such a diviation are considered [ru

Electrochemical reduction of actinides oxides in molten salts

International Nuclear Information System (INIS)

Claux, B.

2011-01-01

Reactive metals are currently produced from their oxide by multiple steps reduction techniques. A one step route from the oxide to the metal has been suggested for metallic titanium production by electrolysis in high temperature molten chloride salts. In the so-called FFC process, titanium oxide is electrochemically reduced at the cathode, generating O 2- ions, which are converted on a graphite anode into carbon oxide or dioxide. After this process, the spent salt can in principle be reused for several batches which is particularly attractive for a nuclear application in terms of waste minimization. In this work, the electrochemical reduction process of cerium oxide (IV) is studied in CaCl 2 and CaCl 2 -KCl melts to understand the oxide reduction mechanism. Cerium is used as a chemical analogue of actinides. Electrolysis on 10 grams of cerium oxide are made to find optimal conditions for the conversion of actinides oxides into metals. The scale-up to hundred grams of oxide is also discussed. (author) [fr

Electrochemical extraction of samarium from molten chlorides in pyrochemical processes

International Nuclear Information System (INIS)

Castrillejo, Y.; Fernandez, P.; Medina, J.; Hernandez, P.; Barrado, E.

2011-01-01

This work concerns the electrochemical extraction of samarium from molten chlorides. In this way, the electrochemical behaviour of samarium ions has been investigated in the eutectic LiCl-KCl at the surface of tungsten, aluminium and aluminium coated tungsten electrodes. On a W inert electrode the electro-reduction of Sm(III) takes place in only one soluble-soluble electrochemical step Sm(III)/Sm(II). The electrochemical system Sm(II)/Sm(0) has not been observed within the electrochemical window, because of the prior reduction of Li(I) ions from the solvent, which inhibits the electro-extraction of Sm species from the salt on such a substrate. Sm metal in contact with the melt react to give Li(0) according to the reaction: Sm(0) + 2Li(I) ↔ Sm(II) + 2Li(0). On the contrary, on reactive Al electrodes the electrochemical system Sm(II)/Sm(0) was observed within the electroactive range. The potential shift of the redox couple is caused by the decrease of Sm activity in the metal phase due to the formation of Sm-Al alloys at the interface. The formation mechanism of the intermetallic compounds was studied in a melt containing: (i) both Sm(III) and Al(III) ions, using W and Al coated tungsten electrodes, and (ii) Sm(III) ions using an Al electrode. Analysis of the samples after potentiostatic electrolysis by X-ray diffraction and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), allowed the identification of Al 3 Sm and Al 2 Sm.

Electrochemical extraction of samarium from molten chlorides in pyrochemical processes

Energy Technology Data Exchange (ETDEWEB)

Castrillejo, Y., E-mail: ycastril@qa.uva.es [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Fernandez, P. [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Medina, J. [Dept Fisica Materia Condensada Cristalografia y Mineralogia, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain); Hernandez, P. [Centro de Investigaciones Quimicas, Universidad Autonoma del Estado de Hidalgo, Carr. Pachuca-Tulancingo Km. 4.5, C.P. 42076 Pachuca, Hidalgo (Mexico); Barrado, E. [QUIANE/Dept Quimica Analitica, F. de Ciencias, Universidad de Valladolid, Prado de la Magdalena s/n, 47005 Valladolid (Spain)

2011-10-01

This work concerns the electrochemical extraction of samarium from molten chlorides. In this way, the electrochemical behaviour of samarium ions has been investigated in the eutectic LiCl-KCl at the surface of tungsten, aluminium and aluminium coated tungsten electrodes. On a W inert electrode the electro-reduction of Sm(III) takes place in only one soluble-soluble electrochemical step Sm(III)/Sm(II). The electrochemical system Sm(II)/Sm(0) has not been observed within the electrochemical window, because of the prior reduction of Li(I) ions from the solvent, which inhibits the electro-extraction of Sm species from the salt on such a substrate. Sm metal in contact with the melt react to give Li(0) according to the reaction: Sm(0) + 2Li(I) {r_reversible} Sm(II) + 2Li(0). On the contrary, on reactive Al electrodes the electrochemical system Sm(II)/Sm(0) was observed within the electroactive range. The potential shift of the redox couple is caused by the decrease of Sm activity in the metal phase due to the formation of Sm-Al alloys at the interface. The formation mechanism of the intermetallic compounds was studied in a melt containing: (i) both Sm(III) and Al(III) ions, using W and Al coated tungsten electrodes, and (ii) Sm(III) ions using an Al electrode. Analysis of the samples after potentiostatic electrolysis by X-ray diffraction and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), allowed the identification of Al{sub 3}Sm and Al{sub 2}Sm.

Uncertainties of Gaseous Oxidized Mercury Measurements Using KCl-Coated Denuders, Cation-Exchange Membranes, and Nylon Membranes: Humidity Influences.

Science.gov (United States)

Huang, Jiaoyan; Gustin, Mae Sexauer

2015-05-19

Quantifying the concentration of gaseous oxidized mercury (GOM) and identifying the chemical compounds in the atmosphere are important for developing accurate local, regional, and global biogeochemical cycles. The major hypothesis driving this work was that relative humidity affects collection of GOM on KCl-coated denuders and nylon membranes, both currently being applied to measure GOM. Using a laboratory manifold system and ambient air, GOM capture efficiency on 3 different collection surfaces, including KCl-coated denuders, nylon membranes, and cation-exchange membranes, was investigated at relative humidity ranging from 25 to 75%. Recovery of permeated HgBr2 on KCl-coated denuders declined by 4-60% during spikes of relative humidity (25 to 75%). When spikes were turned off GOM recoveries returned to 60 ± 19% of permeated levels. In some cases, KCl-coated denuders were gradually passivated over time after additional humidity was applied. In this study, GOM recovery on nylon membranes decreased with high humidity and ozone concentrations. However, additional humidity enhanced GOM recovery on cation-exchange membranes. In addition, reduction and oxidation of elemental mercury during experiments was observed. The findings in this study can help to explain field observations in previous studies.

X-ray diffraction measurements in KCl shocked along [100

International Nuclear Information System (INIS)

D'Almeida, T.; Gupta, Y.M.

2000-01-01

Real time x-ray diffraction measurements were used to examine the polymorphic phase transformation in KCl shocked along the [100] direction. Shock wave continuum data, obtained previously by Hayes, were used to design the experiments and to predict diffraction from KCl shocked to different peak stresses. Here, we present the results obtained below the transition stress: between 1.4 and 2 GPa. Diffraction data obtained were quantitatively related to macroscopic compression. Interplanar spacing measurements revealed isotropic compression of the unit cell in contrast to previously reported results. Above the transition stress, descriptions of the atomic arrangement with respect to shock propagation (not available in the literature) are required for setting up the detection system. Hence, continuum results in combination with various crystallographic considerations were utilized to obtain data above the transition stress

LIFE Materails: Molten-Salt Fuels Volume 8

Energy Technology Data Exchange (ETDEWEB)

Moir, R; Brown, N; Caro, A; Farmer, J; Halsey, W; Kaufman, L; Kramer, K; Latkowski, J; Powers, J; Shaw, H; Turchi, P

2008-12-11

The goals of the Laser Inertial Fusion Fission Energy (LIFE) is to use fusion neutrons to fission materials with no enrichment and minimum processing and have greatly reduced wastes that are not of interest to making weapons. Fusion yields expected to be achieved in NIF a few times per day are called for with a high reliable shot rate of about 15 per second. We have found that the version of LIFE using TRISO fuel discussed in other volumes of this series can be modified by replacing the molten-flibe-cooled TRISO fuel zone with a molten salt in which the same actinides present in the TRISO particles are dissolved in the molten salt. Molten salts have the advantage that they are not subject to radiation damage, and hence overcome the radiation damage effects that may limit the lifetime of solid fuels such as TRISO-containing pebbles. This molten salt is pumped through the LIFE blanket, out to a heat exchanger and back into the blanket. To mitigate corrosion, steel structures in contact with the molten salt would be plated with tungsten or nickel. The salt will be processed during operation to remove certain fission products (volatile and noble and semi-noble fission products), impurities and corrosion products. In this way neutron absorbers (fission products) are removed and neutronics performance of the molten salt is somewhat better than that of the TRISO fuel case owing to the reduced parasitic absorption. In addition, the production of Pu and rare-earth elements (REE) causes these elements to build up in the salt, and leads to a requirement for a process to remove the REE during operation to insure that the solubility of a mixed (Pu,REE)F3 solid solution is not exceeded anywhere in the molten salt system. Removal of the REE will further enhance the neutronics performance. With molten salt fuels, the plant would need to be safeguarded because materials of interest for weapons are produced and could potentially be removed.

LIFE Materails: Molten-Salt Fuels Volume 8

International Nuclear Information System (INIS)

Moir, R.; Brown, N.; Caro, A.; Farmer, J.; Halsey, W.; Kaufman, L.; Kramer, K.; Latkowski, J.; Powers, J.; Shaw, H.; Turchi, P.

2008-01-01

The goals of the Laser Inertial Fusion Fission Energy (LIFE) is to use fusion neutrons to fission materials with no enrichment and minimum processing and have greatly reduced wastes that are not of interest to making weapons. Fusion yields expected to be achieved in NIF a few times per day are called for with a high reliable shot rate of about 15 per second. We have found that the version of LIFE using TRISO fuel discussed in other volumes of this series can be modified by replacing the molten-flibe-cooled TRISO fuel zone with a molten salt in which the same actinides present in the TRISO particles are dissolved in the molten salt. Molten salts have the advantage that they are not subject to radiation damage, and hence overcome the radiation damage effects that may limit the lifetime of solid fuels such as TRISO-containing pebbles. This molten salt is pumped through the LIFE blanket, out to a heat exchanger and back into the blanket. To mitigate corrosion, steel structures in contact with the molten salt would be plated with tungsten or nickel. The salt will be processed during operation to remove certain fission products (volatile and noble and semi-noble fission products), impurities and corrosion products. In this way neutron absorbers (fission products) are removed and neutronics performance of the molten salt is somewhat better than that of the TRISO fuel case owing to the reduced parasitic absorption. In addition, the production of Pu and rare-earth elements (REE) causes these elements to build up in the salt, and leads to a requirement for a process to remove the REE during operation to insure that the solubility of a mixed (Pu,REE)F3 solid solution is not exceeded anywhere in the molten salt system. Removal of the REE will further enhance the neutronics performance. With molten salt fuels, the plant would need to be safeguarded because materials of interest for weapons are produced and could potentially be removed.

Reactions of metal oxides with molten NaPO3 + NaCl mixtures

International Nuclear Information System (INIS)

Kovarskaya, E.N.; Mityakhina, V.S.; Rodionov, Yu.I.; Silin, M.Yu.

1988-01-01

We consider the dissolution mechanism for iron (III), europium(III), and tin(IV) oxides in molten NaPO 3 + NaCl that are responsible for the peak solubilities. We chose Fe 2 O 3 as the basic material since this occurs in large amounts around damaged metal structures in rock salt mines in a proposed zone for storing vitrified radioactive wastes. Solubility measurement and paper chromatography show that Fe 2 O 3 dissolves in molten NaPO 3 + NaCl in air by reaction with the solvent to give double iron and sodium diphosphates and monophosphates in accordance with the initial solution-in-the-melt composition, the degree of equilibration, and the temperature. The elevated solubilities for initial NaCl contents close to 30 mole % are due to sodium triphosphates and tricyclophosphates present in these melts. Moessbauer spectroscopy confirms that double iron, europium and tin diphosphates and monophosphates containing sodium occur in these chloride-polyphosphate melts

Pyrometallurgical separation processes of radionuclides contained in the irradiated nuclear fuel

International Nuclear Information System (INIS)

De Cordoba, Guadalupe; Caravaca, Concha; Quinones, Javier; Gonzalez de la Huebra, Angel

2005-01-01

Faced with the new options for the high level waste management, the ''Partitioning and Transmutation (P and T)'' of the radio nuclides contained in the irradiated nuclear fuel appear as a promising option from different points of view, such as environmental risk, radiotoxic inventory reduction, economic, etc.. The present work is part of a research project called ''PYROREP'' of the 5th FWP of the EU that studied the feasibility of the actinide separation from the rest of fission products contained in the irradiated nuclear fuel by pyrometallurgical processes with the aim of their transmutation. In order to design these processes it is necessary to determine basic thermodynamic and kinetic data of the radionuclides contained in the nuclear fuel in molten salt media. The electrochemical study of uranium, samarium and molybdenum in the eutectic melt LiCl - KCl has been performed at a tungsten electrode in the temperature range of 450 - 600 deg C in order to obtain these basic properties. (Author)

Fundamentals of molten-salt thermal technology

International Nuclear Information System (INIS)

1980-08-01

This book has been published by the Society of Molten-Salt Thermal Technology to publish a part of the achievement of its members. This book is composed of seven chapters. The chapter 1 is Introduction. The chapter 2 explains the physical properties of molten salts, such as thermal behavior, surface tension, viscosity, electrical conductivity and others. The chapter 3 presents the compatibility with construction materials. Corrosion in molten salts, the electrochemical behavior of fluoride ions on carbon electrodes in fluoride melts, the behaviors of hastelloy N and metals in melts are items of this chapter. The equipments and instruments for molten salts are described in chapter 4. The heat transfer in molten salts is discussed in chapter 5. The chapter 6 explains the application of molten salt technology. The molten salt technology can be applied not only to thermal engineering and energy engineering but also to chemical and nuclear engineerings, and the technical fundamentals, current development status, technical problems and the perspective for the future are outlined. The chapter 7 is the summary of this book. The commercialization of molten salt power reactors is discussed at the end of this book. (Kato, T.)

Selective solid-liquid extraction of lithium halide salts using a ditopic macrobicyclic receptor.

Science.gov (United States)

Mahoney, Joseph M; Beatty, Alicia M; Smith, Bradley D

2004-11-29

A ditopic salt receptor that is known to bind and extract solid NaCl, KCl, NaBr, and KBr into organic solution as their contact ion pairs is now shown by NMR and X-ray crystallography to bind and extract solid LiCl and LiBr as water-separated ion pairs. The receptor can transport these salts from an aqueous phase through a liquid organic membrane with a cation selectivity of K+ > Na+ > Li+. However, the selectivity order is strongly reversed when the receptor extracts solid alkali metal chlorides and bromides into organic solution. For a three-component mixture of solid LiCl, NaCl, and KCl, the ratio of salts extracted and complexed to the receptor in CDCl3 was 94:4:2, respectively. The same strong lithium selectivity was also observed in the case of a three-component mixture of solid LiBr, NaBr, and KBr where the ratio of extracted salts was 92:5:3. This observation is attributed to the unusually high solubility of lithium salts in organic solvents. The study suggests that ditopic receptors with an ability to extract solid salts as associated ion pairs may have application in separation processes.

Performance of LiCl Impregnated Mesoporous Material Coating over Corrugated Heat Exchangers in a Solid Sorption Chiller

Directory of Open Access Journals (Sweden)

Hongzhi Liu

2018-06-01

Full Text Available The composite material made by impregnating 40 wt. % lithium chloride (LiCl into the mesopores of a kind of natural porous rock (Wakkanai Siliceous Shale: WSS micropowders (short for “WSS + 40 wt. % LiCl” had been developed previously, and can be regenerated below 100 °C with a cooling coefficient of performance (COP of approximately 0.3 when adopted as a sorbent in a sorption cooler. In this study, experiments have been carried out on an intermittent solid sorption chiller with the WSS + 40 wt. % LiCl coating over two aluminum corrugated heat exchangers. Based on the experimental condition (regeneration temperature of 80 °C, condensation temperature of 30 °C in the desorption process; sorption temperature of 30 °C and evaporation temperature of 12 °C in the sorption process, the water sorption amount changes from 20 wt. % to 70 wt. % in one sorption cooling cycle. Moreover, a specific cooling power (SCP of 86 W/kg, a volumetric specific cooling power (VSCP of 42 W/dm3, and a specific sorption power of 170 W/kg can be achieved with a total sorption and desorption time of 20 min. The obtained cooling COP is approximately 0.16.

The Experiences and Challenges in Drilling into Semi molten or Molten Intrusive in Menengai Geothermal Field

Science.gov (United States)

Mortensen, A. K.; Mibei, G. K.

2017-12-01

Drilling in Menengai has experienced various challenges related to drilling operations and the resource itself i.e. quality discharge fluids vis a vis gas content. The main reason for these challenges is related to the nature of rocks encountered at depths. Intrusives encountered within Menengai geothermal field have been group into three based on their geological characteristics i.e. S1, S2 and S3.Detailed geology and mineralogical characterization have not been done on these intrusive types. However, based on physical appearances, S1 is considered as a diorite dike, S2 is syenite while S3 is molten rock material. This paper summarizes the experiences in drilling into semi molten or molten intrusive (S3).

Heat transfer investigation of molten salts under laminar and turbulent flow regimes

International Nuclear Information System (INIS)

Srivastava, A.K.; Vaidya, A.M.; Maheshwari, N.K.; Vijayan, P.K.

2014-01-01

High temperature reactor and solar thermal power plants use Molten Salt as a coolant, as it has low melting point and high boiling point, enabling us to operate the system at low pressure. Molten fluoride salt (eutectic mixture of LiF-NaF-KF) and molten nitrate salt (mixture of NaNO 3 and KNO 3 in 60:40 ratios by weight) are proposed as a candidate coolant for High Temperature Reactors (HTR) and solar power plant respectively. BARC is developing a 600 MWth pebble bed high temperature reactor, cooled by natural circulation of fluoride salt and capable of supplying process heat at 1000℃ to facilitate hydrogen production by splitting water. Beside this, BARC is also developing a 2MWe solar power tower system using molten nitrate salt as a primary coolant and storage medium. In order to design this, it is necessary to study the heat transfer characteristics of various molten salts. Most of the previous studies related to molten salts are based on the experimental works. These experiments essentially measured the physical properties of molten salts and their heat transfer characteristics. Ferri et al. introduced the property definitions for molten salts in the RELAP5 code to perform transient simulations at the ProvaCollettoriSolari (PCS) test facility. In this paper, a CFD analysis has been performed to study the heat transfer characteristics of molten fluoride salt and molten nitrate salt flowing in a circular pipe for various regimes of flow. Simulation is performed with the help of in-house developed CFD code, NAFA, acronym for Numerical Analysis of Flows in Axi-symmetric geometries. Uniform velocity and temperature distribution are set as the inlet boundary condition and pressure is employed at the outlet boundary condition. The inlet temperature for all simulation is set as 300℃ for nitrate salt and 500℃ for fluoride salt and the operating pressure is 1 atm in both the cases

Effect of the graphite electrode material on the characteristics of molten salt electrolytically produced carbon nanomaterials

International Nuclear Information System (INIS)

Kamali, Ali Reza; Schwandt, Carsten; Fray, Derek J.

2011-01-01

The electrochemical erosion of a graphite cathode during the electrolysis of molten lithium chloride salt may be used for the preparation of nano-structured carbon materials. It has been found that the structures and morphologies of these carbon nanomaterials are dependent on those of the graphite cathodes employed. A combination of tubular and spherical carbon nanostructures has been produced from a graphite with a microstructure of predominantly planar micro-sized grains and a minor fraction of more irregular nano-sized grains, whilst only spherical carbon nanostructures have been produced from a graphite with a microstructure of primarily nano-sized grains. Based on the experimental results, a best-fit regression equation is proposed that relates the crystalline domain size of the graphite reactants and the carbon products. The carbon nanomaterials prepared possess a fairly uniform mesoporosity with a sharp peak in pore size distribution at around 4 nm. The results are of crucial importance to the production of carbon nanomaterials by way of the molten salt electrolytic method. - Highlights: → Carbon nanomaterials are synthesised by LiCl electrolysis with graphite electrodes. → The degree of crystallinity of graphite reactant and carbon product are related. → A graphite reactant is identified that enables the preparation of carbon nanotubes. → The carbon products possess uniform mesoporosity with narrow pore size distribution.

Thorium-based Molten Salt Reactor (TMSR) project in China

International Nuclear Information System (INIS)

Dai, Zhimin; Liu, Wei

2013-01-01

Making great efforts in development of nuclear energy is one of the long-term-plan in China's energy strategies. The advantages of Thorium-based nuclear energy are: rich resource in nature, less nuclear waste, low toxicity, nuclear non-proliferation and so on. Furthermore, China is a country with abundant thorium, thus it is necessary to develop the Thorium-based Molten Salt Reactor (TMSR) in China. Shanghai Institute of Applied Physics, Chinese Academy of Sciences (SINAP) had designed and constructed the first China's light-water reactor and developed a zero-power thorium-based molten salt reactor successfully in the early 1970s. The applied research project 'thorium molten salt reactor nuclear power system' by SINAP together with several other institutes had been accepted and granted by China government in 2011. The whole project has been divided into three stages: Firstly, built a 2 MW-zero-power high temperature solid molten salt reactor in 2015 and a 2 MW-zero-power high temperature liquid molten salt reactor in 2017. Secondly, in 2020 built a 10 MW high temperature liquid molten salt reactor. Thirdly, on the base of previous work, a 100 MW high temperature molten salt reactor should be achieving in 2030. After more than one years of efforts, a high quality scientific research team has been formed, which is able to design the molten salt reactor, the molten salt loop and related key equipment, the systems of molten salt preparation, purification and the radioactive gas removal. In the past one year, the initial physical design of high temperature molten salt reactor has been completed; the nuclear chemistry and radiation chemical laboratory has been built, a high temperature salt (HTS) loop and radioactive gas removal experiment device system have been successfully developed and constructed. Further, the preliminary study on reactor used carbon-carbon composite material has been investigated. (author)

Release and transformation of chlorine and potassium during pyrolysis of KCl doped biomass

DEFF Research Database (Denmark)

Wang, Yang; Wu, Hao; Sárossy, Zsuzsa

2017-01-01

–850 °C), and KCl contents (0–5 wt%). The volatiles were collected and analyzed for CH3Cl concentration by GC–MS. The solid residue was analyzed by ICP-OES for the contents of total and water soluble K and Cl. Considerable amounts of CH3Cl, corresponding to 20–50% of the fuel chlorine, were formed......The formation of CH3Cl and the transformation of chlorine and potassium during pyrolysis of biomass were investigated. Model biomass compounds (cellulose, xylan, lignin and pectin) and pine wood doped with KCl were pyrolysed in a TGA at different heating rates (10–1000 °C/min), temperatures (300...

Molten salt reactors

International Nuclear Information System (INIS)

Bouchter, J.C.; Dufour, P.; Guidez, J.; Simon, N.; Renault, C.

2014-01-01

Molten salt reactors are one of the 6 concepts retained for the 4. generation of nuclear reactors. The principle of this reactor is very innovative: the nuclear fuel is dissolved in the coolant which allows the online reprocessing of the fuel and the online recovery of the fission products. A small prototype: the Molten Salt Reactor Experiment (MSRE - 8 MWt) was operating a few years in the sixties in the USA. The passage towards a fast reactor by the suppression of the graphite moderator leads to the concept of Molten Salt Fast Reactor (MSFR) which is presently studied through different European projects such as MOST, ALISIA and EVOL. Worldwide the main topics of research are: the adequate materials resisting to the high level of corrosiveness of the molten salts, fuel salt reprocessing, the 3-side coupling between neutron transport, thermohydraulics and thermo-chemistry, the management of the changing chemical composition of the salt, the enrichment of lithium with Li 7 in the case of the use of lithium fluoride salt and the use of MSFR using U 233 fuel (thorium cycle). The last part of the article presents a preliminary safety analysis of the MSFR. (A.C.)

Experimental and theoretical studies in Molten Salt Natural Circulation Loop (MSNCL)

International Nuclear Information System (INIS)

Srivastava, A.K.; Borgohain, A.; Jana, S.S.; Bagul, R.K.; Singh, R.R.; Maheshwari, N.K.; Belokar, D.G.; Vijayan, P.K.

2014-12-01

High Temperature Reactors (HTR) and solar thermal power plants use molten salt as a coolant, as it has low melting point and high boiling point, enabling us to operate the system at low pressure. Molten fluoride salt and molten nitrate salt are proposed as a candidate coolant for High Temperature Reactors (HTR) and solar power plant respectively. BARC is developing a 600 MWth pebble bed high temperature reactor, cooled by natural circulation of fluoride salt and capable of supplying process heat at 1000°C to facilitate hydrogen production by splitting water. Beside this, BARC is also developing a 2MWe solar power tower system using molten nitrate salt. With these requirements, a Molten Salt Natural Circulation Loop (MSNCL) has been designed, fabricated, installed and commissioned in Hall-7, BARC for thermal hydraulic, instrumentation development and material compatibility related studies. Steady state natural circulation experiments with molten nitrate salt (mixture of NaNO 3 and KNO 3 in 60:40 ratio) have been carried out in the loop at different power level. Various transients viz. startup of natural circulation, step power change, loss of heat sink and heater trip has also been studied in the loop. A well known steady state correlation given by Vijayan et. al. has been compared with experimental data. In-house developed code LeBENC has also been validated against all steady state and transient experimental results. The detailed description of MSNCL, steady state and transient experimental results and validation of in-house developed code LeBENC have been described in this report. (author)

Strategies to reduce gaseous KCl and chlorine in deposits during combustion of biomass in fluidised bed boilers

Energy Technology Data Exchange (ETDEWEB)

Kassman, Haakan

2012-11-01

Combustion of a biomass with an enhanced content of alkali and chlorine (Cl) can result in operational problems including deposit formation and superheater corrosion. The strategies applied to reduce such problems include co-combustion and the use of additives. In this work, measures were investigated in order to decrease the risk of superheater corrosion by reducing gaseous KCl and the content of chlorine in deposits. The strategies applied were sulphation of KCl by sulphur/sulphate containing additives (i.e. elemental sulphur (S) and ammonium sulphate (AS)) and co-combustion with peat. Both sulphation of KCl and capture of potassium (K) in ash components can be of importance when peat is used. The experiments were mainly performed in a 12 MW circulation fluidised bed (CFB) boiler equipped for research purposes but also in a full-scale CFB boiler. The results were evaluated by means of IACM (on-line measurements of gaseous KCl), conventional gas analysis, deposit and corrosion probe measurements and ash analysis. Ammonium sulphate performed significantly better than elemental sulphur. Thus the presence of SO{sub 3} (i.e. AS) is of greater importance than that of SO{sub 2} (i.e. S) for sulphation of gaseous KCl and reduction of chlorine in deposits. Only a minor reduction of gaseous KCl was obtained during co-combustion with peat although chlorine in the deposits was greatly reduced. This reduction was supposedly due to capture of K by reactive components from the peat ash in parallel to sulphation of KCl. These compounds remained unidentified. The effect of volatile combustibles on the sulphation of gaseous KCl was investigated. The poorest sulphation was attained during injection of ammonium sulphate in the upper part of the combustion chamber during the lowest air excess ratio. The explanation for this is that SO{sub 3} was partly consumed by side reactions due to the presence of combustibles. These experimental results were supported by modelling, although the

Parametric study of natural circulation flow in molten salt fuel in molten salt reactor

Energy Technology Data Exchange (ETDEWEB)

Pauzi, Anas Muhamad, E-mail: Anas@uniten.edu.my [Centre of Nuclear Energy, Universiti Tenaga Nasional (UNITEN), Jalan IKRAM-UNITEN, 43000 Kajang, Selangor (Malaysia); Cioncolini, Andrea; Iacovides, Hector [School of Mechanical, Aerospace, and Civil Engineering (MACE), University of Manchester, Oxford Road, M13 9PL Manchester (United Kingdom)

2015-04-29

The Molten Salt Reactor (MSR) is one of the most promising system proposed by Generation IV Forum (GIF) for future nuclear reactor systems. Advantages of the MSR are significantly larger compared to other reactor system, and is mainly achieved from its liquid nature of fuel and coolant. Further improvement to this system, which is a natural circulating molten fuel salt inside its tube in the reactor core is proposed, to achieve advantages of reducing and simplifying the MSR design proposed by GIF. Thermal hydraulic analysis on the proposed system was completed using a commercial computation fluid dynamics (CFD) software called FLUENT by ANSYS Inc. An understanding on theory behind this unique natural circulation flow inside the tube caused by fission heat generated in molten fuel salt and tube cooling was briefly introduced. Currently, no commercial CFD software could perfectly simulate natural circulation flow, hence, modeling this flow problem in FLUENT is introduced and analyzed to obtain best simulation results. Results obtained demonstrate the existence of periodical transient nature of flow problem, hence improvements in tube design is proposed based on the analysis on temperature and velocity profile. Results show that the proposed system could operate at up to 750MW core power, given that turbulence are enhanced throughout flow region, and precise molten fuel salt physical properties could be defined. At the request of the authors and the Proceedings Editor the name of the co-author Andrea Cioncolini was corrected from Andrea Coincolini. The same name correction was made in the Acknowledgement section on page 030004-10 and in reference number 4. The updated article was published on 11 May 2015.

A reactive distillation process for the treatment of LiCl-KCl eutectic waste salt containing rare earth chlorides

Energy Technology Data Exchange (ETDEWEB)

Eun, H.C., E-mail: ehc2004@kaeri.re.kr; Choi, J.H.; Kim, N.Y.; Lee, T.K.; Han, S.Y.; Lee, K.R.; Park, H.S.; Ahn, D.H.

2016-11-15

The pyrochemical process, which recovers useful resources (U/TRU metals) from used nuclear fuel using an electrochemical method, generates LiCl-KCl eutectic waste salt containing radioactive rare earth chlorides (RECl{sub 3}). It is necessary to develop a simple process for the treatment of LiCl-KCl eutectic waste salt in a hot-cell facility. For this reason, a reactive distillation process using a chemical agent was achieved as a method to separate rare earths from the LiCl-KCl waste salt. Before conducting the reactive distillation, thermodynamic equilibrium behaviors of the reactions between rare earth (Nd, La, Ce, Pr) chlorides and the chemical agent (K{sub 2}CO{sub 3}) were predicted using software. The addition of the chemical agent was determined to separate the rare earth chlorides into an oxide form using these equilibrium results. In the reactive distillation test, the rare earth chlorides in LiCl-KCl eutectic salt were decontaminated at a decontamination factor (DF) of more than 5000, and were mainly converted into oxide (Nd{sub 2}O{sub 3}, CeO{sub 2}, La{sub 2}O{sub 3}, Pr{sub 2}O{sub 3}) or oxychloride (LaOCl, PrOCl) forms. The LiCl-KCl was purified into a form with a very low concentration (<1 ppm) for the rare earth chlorides.

Compatibility studies of potential molten-salt breeder reactor materials in molten fluoride salts

International Nuclear Information System (INIS)

Keiser, J.R.

1977-05-01

The molten fluoride salt compatibility studies carried out during the period 1974--76 in support of the Molten-Salt Reactor Program are summarized. Thermal-convection and forced-circulation loops were used to measure the corrosion rate of selected alloys. Results confirmed the relationship of time, initial chromium concentration, and mass loss developed by previous workers. The corrosion rates of Hastelloy N and Hastelloy N modified by the addition of 1--3 wt percent Nb were well within the acceptable range for use in an MSBR. 13 figures, 3 tables

Electrochemical separation of uranium in the molten system LiF–NaF–KF–UF{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Korenko, M., E-mail: Michal.Korenko@savba.sk [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic); Department of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 36 Bratislava (Slovakia); Straka, M.; Szatmáry, L. [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic); Ambrová, M. [Institute of Inorganic Chemistry, Technology and Materials, Slovak University of Technology, Radlinského 9, SK-812 37 Bratislava (Slovakia); Uhlíř, J. [Fluorine Chemistry Department, Nuclear Research Institute (NRI) Řež Plc., Husinec-Řež 130, CZ-250 68 (Czech Republic)

2013-09-15

This article is focused on the electrochemical investigation (cyclic voltammetry and related studies) of possible reduction of U{sup 4+} ions to metal uranium in the molten system LiF–NaF–KF(eut.)–UF{sub 4} that can provide basis for the electrochemical extraction of uranium from molten salts. Two-step reduction mechanism for U{sup 4+} ions involving one electron exchange in soluble/soluble U{sup 4+}/U{sup 3+} system and three electrons exchange in the second step were found on the nickel working electrode. Both steps were found to be reversible and diffusion controlled. Based on cyclic voltammetry, the diffusion coefficients of uranium ions at 530 °C were found to be D(U{sup 4+}) = 1.64 × 10{sup −5} cm{sup 2} s{sup −1} and D(U{sup 3+}) 1.76 × 10{sup −5} cm{sup 2} s{sup −1}. Usage of the nickel spiral electrode for electrorefining of uranium showed fairly good feasibility of its extraction. However some oxidant present during the process of electrorefining caused that the solid deposits contained different uranium species such as UF{sub 3}, UO{sub 2} and K{sub 3}UO{sub 2}F{sub 5}.

Thermoluminescence of KCl:Eu2+ under ultraviolet irradiation at different temperatures

International Nuclear Information System (INIS)

Aguirre de Carcer, I.; Jaque, F.; Rowlands, A.P.; Townsend, P.D.

1998-01-01

The thermoluminescence of KCl:Eu 2+ ultraviolet irradiated samples has been studied at different temperatures with the aim of optimising its solar dosimetric characteristics. This was achieved by recording with a dosimeter -10 deg. C. Ultraviolet light (254 nm) irradiation under these conditions produces a high TL peak at 90 deg. C which is linear with exposure time over at least four orders of magnitude. The TL emission spectra of KCl:Eu 2+ under UV irradiation have been analysed to reveal component bands at 2.86 eV, 2.97 eV, 3.02 eV, 3.07 eV, 3.14 eV and 3.26 eV that corresponds to divalent europium impurity sites. The new peak at 3.26 eV (297 nm) had not reported before but it has to be considered in order to match the experimental TL emission. A model for the defect site of this new emission is discussed

Molten salts as possible fuel fluids for TRU fuelled systems: ISTC no. 1606 approach

International Nuclear Information System (INIS)

Ignatiev, V.; Zakirov, R.; Grebenkine, K.

2001-01-01

The principle attraction of the molten salt reactor (MSR) technology is the use of fuel/fertile material flexibility (easy of fuel preparation and processing) for gaining additional profits as compared with solid materials. This approach presents important departures from traditional philosophy, applied in current nuclear power plants, and to some extent contradicts the straightforward interpretation of the defence-in-depth principal. Nevertheless we understand there may be potential to use MSR technology to support back end fuel cycle technologies in future commercial environment. The paper aims at reviewing results of the work performed in Russia, relevant to the problems of MSR technology development. Also this contribution aims at evaluation of remaining uncertainties for molten salt burner concept implementation. Fuel properties and behaviour, container materials, and clean-up of fuels with emphasis on experiments will be of priority. Recommendations are made regarding the types of experimental studies needed on a way to implement molten salt technology to the back-end of the fuel cycle. To better understand the potential and limitations of the molten salts as a fuel for reactor of incinerator type, Russian Institutes have submitted to the ISTC the Task no. 1606 Experimental Study of Molten Salt Technology for Safe and Low Waste Treatment of Plutonium and Minor Actinides in Accelerator Driven and Critical Systems. The project goals, technical approach and expected specific results are discussed. (author)

Supercooling of aqueous NaCl and KCl solutions under acoustic levitation.

Science.gov (United States)

Lü, Y J; Wei, B

2006-10-14

The supercooling capability of aqueous NaCl and KCl solutions is investigated at containerless state by using acoustic levitation method. The supercooling of water is obviously enhanced by the alkali metal ions and increases linearly with the augmentation of concentrations. Furthermore, the supercooling depends on the nature of ions and is 2-3 K larger for NaCl solution than that for KCl solution in the present concentration range: Molecular dynamics simulations are performed to reveal the intrinsic correlation between supercoolability and microstructure. The translational and orientational order parameters are applied to quantitatively demonstrate the effect of ionic concentration on the hydrogen-bond network and ice melting point. The disrupted hydrogen-bond structure determines essentially the concentration dependence of supercooling. On the other hand, the introduced acoustic pressure suppresses the increase of supercooling by promoting the growth and coalescence of microbubbles, the effective nucleation catalysts, in water. However, the dissolved ions can weaken this effect, and moreover the degree varies with the ion type. This results in the different supercoolability for NaCl and KCl solutions under the acoustic levitation conditions.

Molten salt thermal energy storage systems: salt selection

Energy Technology Data Exchange (ETDEWEB)

Maru, H.C.; Dullea, J.F.; Huang, V.S.

1976-08-01

A research program aimed at the development of a molten salt thermal energy storage system commenced in June 1976. This topical report describes Work performed under Task I: Salt Selection is described. A total of 31 inorganic salts and salt mixtures, including 9 alkali and alkaline earth carbonate mixtures, were evaluated for their suitability as heat-of-fusion thermal energy storage materials at temperatures of 850 to 1000/sup 0/F. Thermophysical properties, safety hazards, corrosion, and cost of these salts were compared on a common basis. We concluded that because alkali carbonate mixtures show high thermal conductivity, low volumetric expansion on melting, low corrosivity and good stability, they are attractive as heat-of-fusion storage materials in this temperature range. A 35 wt percent Li/sub 2/CO/sub 3/-65 wt percent K/sub 2/CO/sub 3/ (50 mole percent Li/sub 2/CO/sub 3/-50 mole percent K/sub 2/CO/sub 3/) mixture was selected as a model system for further experimental work. This is a eutectoid mixture having a heat of fusion of 148 Btu/lb (82 cal/g) that forms an equimolar compound, LiKCO/sub 3/. The Li/sub 2/CO/sub 3/-K/sub 2/CO/sub 3/ mixture is intended to serve as a model system to define heat transfer characteristics, potential problems, and to provide ''first-cut'' engineering data required for the prototype system. The cost of a thermal energy storage system containing this mixture cannot be predicted until system characteristics are better defined. However, our comparison of different salts indicated that alkali and alkaline earth chlorides may be more attractive from a salt cost point of view. The long-term corrosion characteristics and the effects of volume change on melting for the chlorides should be investigated to determine their overall suitability as a heat-of-fusion storage medium.

Rheological behavior and constitutive equations of heterogeneous titanium-bearing molten slag

Science.gov (United States)

Jiang, Tao; Liao, De-ming; Zhou, Mi; Zhang, Qiao-yi; Yue, Hong-rui; Yang, Song-tao; Duan, Pei-ning; Xue, Xiang-xin

2015-08-01

Experimental studies on the rheological properties of a CaO-SiO2-Al2O3-MgO-TiO2-(TiC) blast furnace (BF) slag system were conducted using a high-temperature rheometer to reveal the non-Newtonian behavior of heterogeneous titanium-bearing molten slag. By measuring the relationships among the viscosity, the shear stress and the shear rate of molten slags with different TiC contents at different temperatures, the rheological constitutive equations were established along with the rheological parameters; in addition, the non-Newtonian fluid types of the molten slags were determined. The results indicated that, with increasing TiC content, the viscosity of the molten slag tended to increase. If the TiC content was less than 2wt%, the molten slag exhibited the Newtonian fluid behavior when the temperature was higher than the critical viscosity temperature of the molten slag. In contrast, the molten slag exhibited the non-Newtonian pseudoplastic fluid characteristic and the shear thinning behavior when the temperature was less than the critical viscosity temperature. However, if the TiC content exceeded 4wt%, the molten slag produced the yield stress and exhibited the Bingham and plastic pseudoplastic fluid behaviors when the temperature was higher and lower than the critical viscosity temperature, respectively. When the TiC content increased further, the yield stress of the molten slag increased and the shear thinning phenomenon became more obvious.

Structure of molten Bi-Sb-alloys by means of neutron diffraction

International Nuclear Information System (INIS)

Lamparter, P.; Knoll, W.; Steeb, S.

1976-01-01

The structural investigations with melts can be subdivided into two groups: The first group contains molten metals and molten alloys, and one can state that the structure of molten metals and of molten alloys nowadays is rather well understood. Interference functions of molten metals may be described by a hard sphere model. This is valid also for molten alloys with statistical distribution. For the second group, namely molten non-metals and molecular melts, the interference functions as well as the pair correlation functions are very offen rather complicated and not well understood. The present study is concerned with the transition region between these two groups. It is shown that the melts of the Bi-Sb system exhibit a change from metallic to non-metallic structure. Regarding the experimental details: the experiments were done with the two-axes spectrometer D 4 at the high-flux reactor at Grenoble. The containers consisted of cylindrical quartz tubes with a wall thickness of 0.1 cm. The furnace consisted of a direct-heated vanadium tube. The wavelength of the neutrons was 0.695 A. The final result is that the structure in molten Bi-Sb-alloys consists of primitive tetrahedra with coordination number 3. There are less tetrahedra in molten Bi than in molten Sb. Also with rising temperature the number of tetrahedra decreases. It is shown how to compose the coordination numbers of two structures to get the observed coordination number. The observed values are always the mean values of the two structures. (orig./HK) [de

Development and characterization of new high-level waste form containing LiCl KCl eutectic salts for achieving waste minimization from pyroprocessing

International Nuclear Information System (INIS)

Cho, Yong Zun; Kim, In Tae; Park, Hwan Seo; Ahn, Byeung Gil; Eun, Hee Chul; Son, Seock Mo; Ah, Su Na

2011-12-01

The purpose of this project is to develop new high level waste (HLW) forms and fabrication processes to dispose of active metal fission products that are removed from electrorefiner salts in the pyroprocessing based fuel cycle. The current technology for disposing of active metal fission products in pyroprocessing involves non selectively discarding of fission product loaded salt in a glass-bonded sodalite ceramic waste form. Selective removal of fission products from the molten salt would greatly minimize the amount of HLW generated and methods were developed to achieve selective separation of fission products during a previous I NERI research project (I NERI 2006 002 K). This I NERI project proceeds from the previous project with the development of suitable waste forms to immobilize the separated fission products. The Korea Atomic Energy Research Institute (KAERI) has focused primarily on developing these waste forms using surrogate waste materials, while the Idaho National Laboratory (INL) has demonstrated fabrication of these waste forms using radioactive electrorefiner salts in hot cell facilities available at INL. Testing and characterization of these radioactive materials was also performed to determine the physical, chemical, and durability properties of the waste forms

Integrated Data Collection Analysis (IDCA) Program - KClO₄/Aluminum Mixture

Energy Technology Data Exchange (ETDEWEB)

Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates (ARA), Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2012-01-17

The Integrated Data Collection Analysis (IDCA) program is conducting a Proficiency Test for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO₄ and aluminum—KClO₄/Al mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solids. The mixture was found to be: 1) much less sensitive to impact than RDX, (LLNL being the exception) and PETN, 2) more sensitive to friction than RDX and PETN, and 3) extremely sensitive to spark. The thermal analysis showed little or no exothermic character. One prominent endothermic feature was observed in the temperature range studied and identified as a phase transition of KClO₄.

Electrochemical separation of cerium and yttrium in molten chlorides on liquid-metallic electrodes

International Nuclear Information System (INIS)

Yamshchikov, L.F.; Lebedev, V.A.; Nichkov, I.F.

1978-01-01

An estimating calculation of the coefficients of separation of cerium and yttrium in the process of electrolysis in molten salts on liquid electrodes of aluminium, gallium, indium, lead, tin, antimonium and zinc is carried out. The calculation of the separation coefficients was carried out according to the known values of activation coefficients of cerium and yttrium in fusible metals. The electrolysis was carried out at 973 K in the argon air in the cell with an eutectic mixture of NaCl and KCl as an elactrolyte. It is shown that the salten phase is concentrated by yttrium, and the melallic one- by cerium on all the electrodes. The value of the separation coefficient of Ce and Y is considerably high and continuously increases on the fusible metals in the Zn, In, Ga, Al, Pb, Sn, Sb series. The experimental values of the separation coefficients practically coincide with the theoretically calculated ones, testifying to the possibility of the effective separation of elements even in a single-staged possibility of the effective separation of elements even in a single-staged process. An electrolysis of molten salts is not inferior in its selectivity to the universally recognized methods of the fine purification of substances permitting to separate Ce and Y with the Ksub(sep) approximately equal to 10

Accelerator molten-salt breeding and thorium fuel cycle

International Nuclear Information System (INIS)

Furukawa, Kazuo; Nakahara, Yasuaki; Kato, Yoshio; Ohno, Hideo; Mitachi, Kohshi.

1990-01-01

The recent efforts at the development of fission energy utilization have not been successful in establishing fully rational technology. A new philosophy should be established on the basis of the following three principles: (1) thorium utilization, (2) molten-salt fuel concept, and (3) separation of fissile-breeding and power-generating functions. Such philosophy is called 'Thorium Molten-Salt Nuclear Energy Synergetics [THORIMS-NES]'. The present report first addresses the establishment of 233 U breeding fuel cycle, focusing on major features of the Breeding and Chemical Processing Centers and a small molten-salt power station (called FUJI-II). The development of fissile producing breeders is discussed in relation to accelerator molten-salt breeder (AMSB), impact fusion molten-salt breeder, and inertial-confined fusion hybrid molten-salt breeder. Features of the accelerator molten-salt breeder are described, focusing on technical problems with accelerator breeders (or spallators), design principle of the accelerator molten-salt breeder, selection of molten salt compositions, and nuclear- and reactor-chemical aspects of AMSB. Discussion is also made of further research and development efforts required in the future for AMSB. (N.K.)

Simulation of NaCl and KCl mass transfer during salting of Prato cheese in brine with agitation: a numerical solution

Directory of Open Access Journals (Sweden)

E. Bona

2007-09-01

Full Text Available The association of dietary NaCl with arterial hypertension has led to a reduction in the levels of this salt in cheeses. For salting, KCl has been used as a partial substitute for NaCl, which cannot be completely substituted without affecting product acceptability. In this study a sensorially adequate saline solution (NaCl/KCl was simultaneously diffused during salting of Prato cheese in brine with agitation. The simultaneous multicomponent diffusion during the process was modeled with Fick’s second generalized law. The system of partial differential equations formed was solved by the finite element method (FEM. In the experimental data concentration the deviation for NaCl was of 7.3% and for KCl of 5.4%, both of which were considered acceptable. The simulation of salt diffusion will allow control and modulation of salt content in Prato cheese, permitting the prediction of final content from initial conditions.

An experimental test plan for the characterization of molten salt thermochemical properties in heat transport systems

International Nuclear Information System (INIS)

Calderoni, Pattrick

2010-01-01

Molten salts are considered within the Very High Temperature Reactor program as heat transfer media because of their intrinsically favorable thermo-physical properties at temperatures starting from 300 C and extending up to 1200 C. In this context two main applications of molten salt are considered, both involving fluoride-based materials: as primary coolants for a heterogeneous fuel reactor core and as secondary heat transport medium to a helium power cycle for electricity generation or other processing plants, such as hydrogen production. The reference design concept here considered is the Advanced High Temperature Reactor (AHTR), which is a large passively safe reactor that uses solid graphite-matrix coated-particle fuel (similar to that used in gas-cooled reactors) and a molten salt primary and secondary coolant with peak temperatures between 700 and 1000 C, depending upon the application. However, the considerations included in this report apply to any high temperature system employing fluoride salts as heat transfer fluid, including intermediate heat exchangers for gas-cooled reactor concepts and homogeneous molten salt concepts, and extending also to fast reactors, accelerator-driven systems and fusion energy systems. The purpose of this report is to identify the technical issues related to the thermo-physical and thermo-chemical properties of the molten salts that would require experimental characterization in order to proceed with a credible design of heat transfer systems and their subsequent safety evaluation and licensing. In particular, the report outlines an experimental R and D test plan that would have to be incorporated as part of the design and operation of an engineering scaled facility aimed at validating molten salt heat transfer components, such as Intermediate Heat Exchangers. This report builds on a previous review of thermo-physical properties and thermo-chemical characteristics of candidate molten salt coolants that was generated as part

An experimental test plan for the characterization of molten salt thermochemical properties in heat transport systems

Energy Technology Data Exchange (ETDEWEB)

Pattrick Calderoni

2010-09-01

Molten salts are considered within the Very High Temperature Reactor program as heat transfer media because of their intrinsically favorable thermo-physical properties at temperatures starting from 300 C and extending up to 1200 C. In this context two main applications of molten salt are considered, both involving fluoride-based materials: as primary coolants for a heterogeneous fuel reactor core and as secondary heat transport medium to a helium power cycle for electricity generation or other processing plants, such as hydrogen production. The reference design concept here considered is the Advanced High Temperature Reactor (AHTR), which is a large passively safe reactor that uses solid graphite-matrix coated-particle fuel (similar to that used in gas-cooled reactors) and a molten salt primary and secondary coolant with peak temperatures between 700 and 1000 C, depending upon the application. However, the considerations included in this report apply to any high temperature system employing fluoride salts as heat transfer fluid, including intermediate heat exchangers for gas-cooled reactor concepts and homogenous molten salt concepts, and extending also to fast reactors, accelerator-driven systems and fusion energy systems. The purpose of this report is to identify the technical issues related to the thermo-physical and thermo-chemical properties of the molten salts that would require experimental characterization in order to proceed with a credible design of heat transfer systems and their subsequent safety evaluation and licensing. In particular, the report outlines an experimental R&D test plan that would have to be incorporated as part of the design and operation of an engineering scaled facility aimed at validating molten salt heat transfer components, such as Intermediate Heat Exchangers. This report builds on a previous review of thermo-physical properties and thermo-chemical characteristics of candidate molten salt coolants that was generated as part of the

Research on Wetting-Drying Cycles’ Effect on the Physical and Mechanical Properties of Expansive Soil Improved by OTAC-KCl

Directory of Open Access Journals (Sweden)

Bao-tian Wang

2015-01-01

Full Text Available Expansive soil experiences periodic swelling and shrinkage during the alternate wet and dry environments, which will result in severe damage to the slope stability. In this study, a promising modifier OTAC-KCl is introduced, which has a good diffusivity and is soluble in water or other solvents easily. Firstly, a reasonable combination of ameliorant 0.3% STAC and 3% KCl is chosen referring to the free swell test. Then, the best curing period, 14 days, is gotten from UCS tests. The effect of wetting and drying cycles on engineering properties of expansive soil improved by OTAC-KCl admixtures after 14-day curing is also studied accordingly. Both treated and untreated expansive soil samples are prepared for the cyclic wetting-drying tests which mainly include cyclic swelling potential and cyclic strength tests. Experimental results show that the swelling potential of expansive soil samples stabilized with OTAC-KCl is suppressed efficiently, and the untreated soil specimens will collapse when immersed in water while the treated specimens keep in good conditions. Moreover, expansive soil samples modified with 0.3% OTAC + 3% KCl show enough durability on the swelling ability, shear strength, and unconfined compressive strength, which means, that both the physical and the mechanical properties of stabilized expansive soil have been improved effectively.

Electrochemical studies in molten sodium fluoroborate

International Nuclear Information System (INIS)

Brigaudeau, M.; Wagner, J.F.

1979-01-01

Physical properties of sodium fluoroborate are recalled and first results obtained during experimental study of molten NaBF 4 are exposed. The system Cu/CuF is used as an indicator of fluoride ion activity and dissociation constant of the solvent is determined by adding NaF to NaBF 4 saturated with BF 3 at a pressure of 1 atm and found equal to 2.7x10 -3 [fr

Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

Energy Technology Data Exchange (ETDEWEB)

Ignatiev, Victor; Feynberg, Olga; Merzlyakov, Aleksandr; Surenkov, Aleksandr [Russian Research Center - Kurchatov Institute, Kurchatov sq. 1, Moscow, RF, 123182 (Russian Federation); Subbotin, Vladimir; Zakirov, Raul; Toropov, Andrey; Panov, Aleksandr [Russian Federal Nuclear Center - Institute of Technical Physics, Snezhinsk (Russian Federation); Afonichkin, Valery [Institute of High-Temperature Electrochemistry, Ekaterinburg (Russian Federation)

2008-07-01

To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF{sub 3}) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the {sup 7}Li,Na,Be/F and {sup 7}Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

International Nuclear Information System (INIS)

Ignatiev, Victor; Feynberg, Olga; Merzlyakov, Aleksandr; Surenkov, Aleksandr; Subbotin, Vladimir; Zakirov, Raul; Toropov, Andrey; Panov, Aleksandr; Afonichkin, Valery

2008-01-01

To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF 3 ) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the 7 Li,Na,Be/F and 7 Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

Design study on advanced nuclear fuel recycle system. Conceptual design study of recycle system using molten salt

International Nuclear Information System (INIS)

Kasai, Y.; Kakehi, I.; Moro, T.; Higashi, T.; Tobe, K.; Kawamura, F.; Yonezawa, S.; Yoshiuji, T.

1998-10-01

Advanced recycle system engineering group of OEC (Oarai Engineering Center) has being carried out a design study of the advanced nuclear fuel recycle system using molten salt (electro-metallurgical process). This system is aiming for improvements of fuel cycle economy and reduction of environmental burden (MA recycles, Minimum of radioactive waste disposal), and also improvement of safety and nuclear non-proliferation. This report describes results of the design study that has been continued since December 1996. (1) A design concept of the advanced nuclear fuel recycle system, that is a module type recycles system of pyrochemical reprocessing and fuel re-fabrication was studied. The module system has advantage in balance of Pu recycle where modules are constructed in coincidence with the construction plan of nuclear power plants, and also has flexibility for technology progress. A demonstration system, minimum size of the above module, was studies. This system has capacity of 10 tHM/y and is able to demonstrate recycle technology of MOX fuel, metal fuel and nitride fuel. (2) Each process of the system, which are pyrochemical electrorefining system, cathode processor, de-cladding system, waste disposal system, etc., were studied. In this study, capacity of an electrorefiner was discussed, and vitrification experiment of molten salt using lead-boric acid glass was conducted. (3) A hot cell system and material handling system of the demonstration system was studied. A robot driven by linear motor was studied for the handling system, and an arrangement plan of the cell system was made. Criticality analysis in the cell system and investigation of material accountancy system of the recycle plant were also made. This design study will be continued in coincidence with design study of reactor and fuel, aiming to establish the concept of FBR recycle system. (author)

Dynamics and control of molten-salt breeder reactor

Energy Technology Data Exchange (ETDEWEB)

Sing, Vikram; Lish, Matthew R.; Chvala, Ondrej; Upadhyaya, Belle R. [Dept. of Nuclear Engineering, University of Tennessee, Knoxville (United States)

2017-08-15

Preliminary results of the dynamic analysis of a two-fluid molten-salt breeder reactor (MSBR) system are presented. Based on an earlier work on the preliminary dynamic model of the concept, the model presented here is nonlinear and has been revised to accurately reflect the design exemplified in ORNL-4528. A brief overview of the model followed by results from simulations performed to validate the model is presented. Simulations illustrate stable behavior of the reactor dynamics and temperature feedback effects to reactivity excursions. Stable and smooth changes at various nodal temperatures are also observed. Control strategies for molten-salt reactor operation are discussed, followed by an illustration of the open-loop load-following capability of the molten-salt breeder reactor system. It is observed that the molten-salt breeder reactor system exhibits “self-regulating” behavior, minimizing the need for external controller action for load-following maneuvers.

Dynamics and control of molten-salt breeder reactor

Directory of Open Access Journals (Sweden)

Vikram Singh

2017-08-01

Full Text Available Preliminary results of the dynamic analysis of a two-fluid molten-salt breeder reactor (MSBR system are presented. Based on an earlier work on the preliminary dynamic model of the concept, the model presented here is nonlinear and has been revised to accurately reflect the design exemplified in ORNL-4528. A brief overview of the model followed by results from simulations performed to validate the model is presented. Simulations illustrate stable behavior of the reactor dynamics and temperature feedback effects to reactivity excursions. Stable and smooth changes at various nodal temperatures are also observed. Control strategies for molten-salt reactor operation are discussed, followed by an illustration of the open-loop load-following capability of the molten-salt breeder reactor system. It is observed that the molten-salt breeder reactor system exhibits “self-regulating” behavior, minimizing the need for external controller action for load-following maneuvers.

Molten salt electrorefining method

International Nuclear Information System (INIS)

Tanaka, Hiroshi; Nakamura, Hitoshi; Shoji, Yuichi; Matsumaru, Ken-ichi.

1994-01-01

A molten cadmium phase (lower side) and a molten salt phase (upper side) are filled in an electrolytic bath. A basket incorporating spent nuclear fuels is inserted/disposed in the molten cadmium phase. A rotatable solid cathode is inserted/disposed in the molten salt phase. The spent fuels, for example, natural uranium, incorporated in the basket is dissolved in the molten cadmium phase. In this case, the uranium concentration in the molten salt phase is determined as from 0.5 to 20wt%. Then, electrolysis is conducted while setting a stirring power for stirring at least the molten salt phase of from 2.5 x 10 2 to 1 x 10 4 based on a reynolds number. Crystalline nuclei of uranium are precipitated uniformly on the surface of the solid cathode, and they grow into fine dendrites. With such procedures, since short-circuit between the cathode precipitates and the molten cadmium phase (anode) is scarcely caused, to improve the recovering rate of uranium. (I.N.)

Study of the reaction between Uranium(III) and Lanthanide oxide by using the UV-VIS spectrophotometer

International Nuclear Information System (INIS)

Kim, Tack-Jin; Cho, Young-Hwan; Choi, In-Kyu; Choi, Kwang-Soon; Jee, Kwang-Yong

2006-01-01

Recently, ionic melts have become attractive reaction media in many fields. Molten salt based electrochemical processes have been proposed as a promising method for future nuclear programs and more specifically for spent fuel processing. Molten alkaline chloride based melts are considered as a promising reaction media. For this, it is interesting to understand the chemical nature of the actinides and lanthanides in high-temperature melt. Some spectroscopy provides essential information on the exact nature of f-block elements LiCl-KCl melt system. The knowledge on the basic chemical properties of these lanthanide oxides and U(III) in molten salt media is essential for developing suitable processes. However, few studies have been reported until now on the interaction between U metal and lanthanide oxides in LiCl-KCl melt. So, we studied the interaction between U(III) and Ln(III) by using the UV-VIS spectra. UV-vis spectrometry is a strong analytical technique for characterizing chemical species and their behavior in molten salt

Gamma coloration of mixed crystals of KCl-KBr doped with Pb2+

International Nuclear Information System (INIS)

Cruz Z, E.; Negron, A.; Ramos A, A.; Ramos B, S.; Hernandez A, J.; Jaque, F; Murrieta S, H.

2001-01-01

The amount of the first stage coloration in KCl 1-x Br x doped with Pb 2+ has been investigated as a function of the dose rate and impurity concentration. For a dose rate of 12.88 kGy/h, the F color center production was independent of the quantity of Pb 2+ , and varied according to the ratio KCl/KBr. At a proportion of 50% of each halogen the typical stages were observed. However, if the dose rate is less than 3.22 kGy/h, the coloration production depends on the quantity of Pb 2+ . (author)

Preparation of tungsten coatings on graphite by electro-deposition via Na{sub 2}WO{sub 4}–WO{sub 3} molten salt system

Energy Technology Data Exchange (ETDEWEB)

Sun, Ning-bo [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Zhang, Ying-chun, E-mail: zycustb@163.com [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Jiang, Fan; Lang, Shao-ting [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Xia, Min [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Institute of Powder Metallurgy and Advanced Ceramics, Southwest Jiaotong University, 111, 1st Section, Northern 2nd Ring Road, Chengdu (China)

2014-11-15

Highlights: • Tungsten coatings on graphite were firstly obtained by electro-deposition method via Na{sub 2}WO{sub 4}–WO{sub 3} molten salt system. • Uniform and dense tungsten coatings could be easily prepared in each face of the sample, especially the complex components. • The obtained tungsten coatings are with high purity, ultra-low oxygen content (about 0.022 wt%). • Modulate pulse parameters can get tungsten coatings with different thickness and hardness. - Abstract: Tungsten coating on graphite substrate is one of the most promising candidate materials as the ITER plasma facing components. In this paper, tungsten coatings on graphite substrates were fabricated by electro-deposition from Na{sub 2}WO{sub 4}–WO{sub 3} molten salt system at 1173 K in atmosphere. Tungsten coatings with no impurities were successfully deposited on graphite substrates under various pulsed current densities in an hour. By increasing the current density from 60 mA cm{sup −2} to 120 mA cm{sup −2} an increase of the average size of tungsten grains, the thickness and the hardness of tungsten coatings occurs. The average size of tungsten grains can reach 7.13 μm, the thickness of tungsten coating was in the range of 28.8–51 μm, and the hardness of coating was higher than 400 HV. No cracks or voids were observed between tungsten coating and graphite substrate. The oxygen content of tungsten coating is about 0.022 wt%.

Thorium Molten-Salt Nuclear Energy Synergetics

International Nuclear Information System (INIS)

Furukawa, Kazuo; Lecocq, A.; Kato, Yoshio; Mitachi, Kohshi.

1990-01-01

In the next century, the 'fission breeder' concept will not be practical to solve the global energy problems, including environmental and North-South problems. As a new measure, a simple rational Th molten salt breeding fuel cycle system, named 'Thorium Molten-Salt Nuclear Energy Synergetics (THORIMS-NES)', which composed of simple power stations and fissile producers, is proposed. This is effective to establish the essential improvement in issues of resources, safety, power-size flexibility, anti-nuclear proliferation and terrorism, radiowaste, economy, etc. securing the simple operation, maintenance, chemical processing, and rational breeding fuel cycle. As examples, 155 MWe fuel self-sustaining power station 'FUJI-II', 7 MWe pilot-plant 'miniFUJI-II', 1 GeV-300 mA proton Accelerator Molten-Salt Breeder 'AMSB', and their combined fuel cycle system are explained. (author)

Boric Ester-Type Molten Salt via Dehydrocoupling Reaction

Directory of Open Access Journals (Sweden)

Noriyoshi Matsumi

2014-11-01

Full Text Available Novel boric ester-type molten salt was prepared using 1-(2-hydroxyethyl-3-methylimidazolium chloride as a key starting material. After an ion exchange reaction of 1-(2-hydroxyethyl-3-methylimidazolium chloride with lithium (bis-(trifluoromethanesulfonyl imide (LiNTf2, the resulting 1-(2-hydroxyethyl-3-methylimidazolium NTf2 was reacted with 9-borabicyclo[3.3.1]nonane (9-BBN to give the desired boric ester-type molten salt in a moderate yield. The structure of the boric ester-type molten salt was supported by 1H-, 13C-, 11B- and 19F-NMR spectra. In the presence of two different kinds of lithium salts, the matrices showed an ionic conductivity in the range of 1.1 × 10−4–1.6 × 10−5 S cm−1 at 51 °C. This was higher than other organoboron molten salts ever reported.

Electric conductivity of low-temperature molten electrolyte KF-AlF3 with additions of LiF and Al2O3

International Nuclear Information System (INIS)

Apisarov, A.P.; Kryukovskij, V.A.; Zajkov, Yu.P.; Red'kin, A.A.; Tkacheva, O.Yu.; Khokhlov, V.A.

2007-01-01

Electric conductivity of LiF, Al 2 O 3 doped KF-AlF 3 (Cryolite Ratio CR=1.3) molten electrolytes was estimated on the basis of empiric equations. Specific electric conductivity of KF-AlF 3 , KF-AIF 3 -AI 2 O 3 , KF-AlF 3 -LiF, KF-AlF 3 -LiF-Al 2 0 3 molten mixtures was measured in the range 687-797 Deg C. Cells with the pyrolytic boron nitride capillary and parallel molybdena electrodes were applied for the determination of electric conductivity. Comparison of calculated and experimental data of the specific electric conductivity of cryolite-alumina melts confirms that the offered model of the calculation adequate represents temperature and concentration dependencies, and it permits forecasting its change under the introduction of different additives in electrolyte [ru

Tunable molten oxide pool assisted plasma-melter vitrification systems

Science.gov (United States)

Titus, Charles H.; Cohn, Daniel R.; Surma, Jeffrey E.

1998-01-01

The present invention provides tunable waste conversion systems and apparatus which have the advantage of highly robust operation and which provide complete or substantially complete conversion of a wide range of waste streams into useful gas and a stable, nonleachable solid product at a single location with greatly reduced air pollution to meet air quality standards. The systems provide the capability for highly efficient conversion of waste into high quality combustible gas and for high efficiency conversion of the gas into electricity by utilizing a high efficiency gas turbine or an internal combustion engine. The solid product can be suitable for various commercial applications. Alternatively, the solid product stream, which is a safe, stable material, may be disposed of without special considerations as hazardous material. In the preferred embodiment, the arc plasma furnace and joule heated melter are formed as a fully integrated unit with a common melt pool having circuit arrangements for the simultaneous independently controllable operation of both the arc plasma and the joule heated portions of the unit without interference with one another. The preferred configuration of this embodiment of the invention utilizes two arc plasma electrodes with an elongated chamber for the molten pool such that the molten pool is capable of providing conducting paths between electrodes. The apparatus may additionally be employed with reduced use or without further use of the gases generated by the conversion process. The apparatus may be employed as a net energy or net electricity producing unit where use of an auxiliary fuel provides the required level of electricity production. Methods and apparatus for converting metals, non-glass forming waste streams and low-ash producing inorganics into a useful gas are also provided. The methods and apparatus for such conversion include the use of a molten oxide pool having predetermined electrical, thermal and physical

Molten salts and nuclear energy production

International Nuclear Information System (INIS)

Le Brun, Christian

2007-01-01

Molten salts (fluorides or chlorides) were considered near the beginning of research into nuclear energy production. This was initially due to their advantageous physical and chemical properties: good heat transfer capacity, radiation insensitivity, high boiling point, wide range solubility for actinides. In addition it was realised that molten salts could be used in numerous situations: high temperature heat transfer, core coolants with solid fuels, liquid fuel in a molten salt reactor, solvents for spent nuclear solid fuel in the case of pyro-reprocessing and coolant and tritium production in the case of fusion. Molten salt reactors, one of the six innovative concepts chosen by the Generation IV international forum, are particularly interesting for use as either waste incinerators or thorium cycle systems. As the neutron balance in the thorium cycle is very tight, the possibility to perform online extraction of some fission product poisons from the salt is very attractive. In this article the most important questions that must be addressed to demonstrate the feasibility of molten salt reactor will be reviewed

Controlling the discharge of molten material

International Nuclear Information System (INIS)

Geel, J. van; Dobbels, F.; Theunissen, W.

1980-01-01

A method and device are described for controlling the discharge of molten material from a melter or an intermediate vessel, in which a primary outflow is fed to an overflow system, the working level of which is regulated by means of pneumatic pressure on a communicating chamber pertaining to the overflow system. Molten material may be led into a primary overflow by means of a pneumatic lift. The material melted may be a glass used for disposing of radioactive liquid wastes. (author)

Computational Analysis of Nanoparticles-Molten Salt Thermal Energy Storage for Concentrated Solar Power Systems

Energy Technology Data Exchange (ETDEWEB)

Kumar, Vinod [Univ. of Texas, El Paso, TX (United States)

2017-05-05

High fidelity computational models of thermocline-based thermal energy storage (TES) were developed. The research goal was to advance the understanding of a single tank nanofludized molten salt based thermocline TES system under various concentration and sizes of the particles suspension. Our objectives were to utilize sensible-heat that operates with least irreversibility by using nanoscale physics. This was achieved by performing computational analysis of several storage designs, analyzing storage efficiency and estimating cost effectiveness for the TES systems under a concentrating solar power (CSP) scheme using molten salt as the storage medium. Since TES is one of the most costly but important components of a CSP plant, an efficient TES system has potential to make the electricity generated from solar technologies cost competitive with conventional sources of electricity.

Visualization of steam bubbles with evaporation in molten alloy

International Nuclear Information System (INIS)

Nishi, Yoshihisa; Furuya, Masahiro; Kinoshita, Izumi; Takenaka, Nobuyuki; Matsubayashi, Masahito

1997-01-01

An innovative Steam Generator concept of Fast Breeder Reactors by using liquid-liquid direct contact heat transfer has been developed. In this concept, the SG shell is filled with a molten alloy heated by primary sodium. Water is fed into the high temperature molten alloy, and evaporates by direct contact heating. In order to obtain the fundamental information to discuss the heat transfer mechanisms of the direct contact between the water and the molten alloy, this phenomenon was visualized by neutron radiography. JRR-3M radiography in Japan Atomic Energy Research Institute was used. Followings are main results. (1) The bubbles with evaporation are risen with vigorous form changing, coalescence and break-up. Because of these vigorous evaporation, this system have the high heat transfer performance. (2) The rising velocities and volumes of bubbles are calculated from pixcel values of images. The velocities of the bubbles with evaporation are about 60 cm/s, which is larger than that of inert gas bubbles in molten alloy (20-40 cm/s). (3) The required heat transfer length of evaporation is calculated from pixcel values of images. The relation between heat transfer length and superheat temperature, obtained through the heat transfer test, is conformed by this calculation. (author)

A method of measuring a molten metal liquid pool volume

Science.gov (United States)

Garcia, G.V.; Carlson, N.M., Donaldson, A.D.

1990-12-12

A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figs.

Accelerator molten-salt breeder reactor

International Nuclear Information System (INIS)

Furukawa, Kazuo; Kuroi, Hideo; Kato, Yoshio; Oomichi, Toshihiko.

1979-01-01

Purpose: To obtain fission products and to transmute transuranium elements and other radioactive wastes by the use of Accelerator Molten-Salt Breeder Reactor. Constitution: Beams from an accelerator pipe at one end of a target vessel is injected through a window into target molten salts filled inside of the target vessel. The target molten salts are subjected to pump recycling or spontaneous convection while forcively cooled by blanket molten salts in an outer vessel. Then, energy is recovered from the blanket molten salts or the target molten salts at high temperatures through electric power generation or the like. Those salts containing such as thorium 232 and uranium 238 are used as the blanket molten salts so that fission products may be produced by neutrons generated in the target molten salts. PbCl 2 -PbF 2 and LiF-BeF 2 -ThF 4 can be used as the target molten salts and as the blanket molten salts respectively. (Seki, T.)

K-Cl cotransporters, cell volume homeostasis, and neurological disease.

Science.gov (United States)

Kahle, Kristopher T; Khanna, Arjun R; Alper, Seth L; Adragna, Norma C; Lauf, Peter K; Sun, Dandan; Delpire, Eric

2015-08-01

K(+)-Cl(-) cotransporters (KCCs) were originally characterized as regulators of red blood cell (RBC) volume. Since then, four distinct KCCs have been cloned, and their importance for volume regulation has been demonstrated in other cell types. Genetic models of certain KCCs, such as KCC3, and their inhibitory WNK-STE20/SPS1-related proline/alanine-rich kinase (SPAK) serine-threonine kinases, have demonstrated the evolutionary necessity of these molecules for nervous system cell volume regulation, structure, and function, and their involvement in neurological disease. The recent characterization of a swelling-activated dephosphorylation mechanism that potently stimulates the KCCs has pinpointed a potentially druggable switch of KCC activity. An improved understanding of WNK/SPAK-mediated KCC cell volume regulation in the nervous system might reveal novel avenues for the treatment of multiple neurological diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of NaCl substitution by KCl on telemea cheese properties

Directory of Open Access Journals (Sweden)

Mihai ANGHELOIU

2016-12-01

Full Text Available The effect of partial or total substitution of sodium chloride by potassium chloride on the chemical composition, texture profile and sensory properties of Telemea cheese during 28 days of ripening at 4°C was evaluated in the current study. Telemea cheese was ripened in 4 different brine solutions (20%, wt/wt made from different NaCl:KCl ratios as follows: (NaCl (A, KCl (B, 1NaCl:1KCl (C and 1NaCl:2KCl (D. The physicochemical properties of Telemea cheese (dry matter, fat, protein, ash, pH, total nitrogen (TN, water soluble nitrogen (WSN and ripening degree values were determined after 1, 7, 14, 21 and 28 days of ripening. Dry matter, pH and ripening degree values were significantly (p < 0.05 affected during ripening. The results of this study indicated that replacing 66% NaCl with KCl influenced the texture profile and sensorial characteristics of Telemea cheese.

Modernization at the Y-12 National Security Complex: A Case for Additional Experimental Benchmarks

Energy Technology Data Exchange (ETDEWEB)

Thornbury, M. L. [Y-12 National Security Complex, Oak Ridge, TN (United States); Juarez, C. [Y-12 National Security Complex, Oak Ridge, TN (United States); Krass, A. W. [Y-12 National Security Complex, Oak Ridge, TN (United States)

2017-08-14

Efforts are underway at the Y-12 National Security Complex (Y-12) to modernize the recovery, purification, and consolidation of un-irradiated, highly enriched uranium metal. Successful integration of advanced technology such as Electrorefining (ER) eliminates many of the intermediate chemistry systems and processes that are the current and historical basis of the nuclear fuel cycle at Y-12. The cost of operations, the inventory of hazardous chemicals, and the volume of waste are significantly reduced by ER. It also introduces unique material forms and compositions related to the chemistry of chloride salts for further consideration in safety analysis and engineering. The work herein briefly describes recent investigations of nuclear criticality for 235UO2Cl2 (uranyl chloride) and 6LiCl (lithium chloride) in aqueous solution. Of particular interest is the minimum critical mass of highly enriched uranium as a function of the molar ratio of 6Li to 235U. The work herein also briefly describes recent investigations of nuclear criticality for 235U metal reflected by salt mixtures of 6LiCl or 7LiCl (lithium chloride), KCl (potassium chloride), and 235UCl3 or 238UCl3 (uranium tri-chloride). Computational methods for analysis of nuclear criticality safety and published nuclear data are employed in the absence of directly relevant experimental criticality benchmarks.

Hydrothermal growth of ZnO nanorods: The role of KCl in controlling rod morphology

International Nuclear Information System (INIS)

Downing, Jonathan M.; Ryan, Mary P.; McLachlan, Martyn A.

2013-01-01

The role of potassium chloride (KCl) in controlling ZnO nanorod morphology of large area thin films prepared by hydrothermal growth has been extensively investigated. The influence of KCl and growth time on the orientation, morphology and microstructure of the nanorod arrays has been studied with systematic changes in the length, width, density and termination of the nanorods observed. Such changes are attributed to stabilization of the high-energy (002) nanorod surface by the KCl. At low KCl concentrations (< 100 mM) c-axis growth i.e. perpendicular to the polar surface, dominates, leading to nanorods with increased length over the control sample (0 mM KCl). At higher concentrations (> 100 mM) stabilization of the high-energy surface by KCl occurs and planar (002) facets are observed accompanied by increased lateral (100) growth, at the highest KCl concentrations near coalesced (002) terminated rods are observed. Additionally we correlate the KCl concentration with the uniformity of the nanorod arrays; a decrease in polydispersity with increased KCl concentration is observed. The vertical alignment of nanorod arrays was studied using X-ray diffraction, it was found that this parameter increases as growth time and KCl concentration are increased. We propose that the increase in vertical alignment is a result of nanorod–nanorod interactions during the early stages of growth. - Highlights: • Modified hydrothermal growth was used for controlled ZnO nanorod synthesis. • Growth conditions varied to study influence on nanorod morphology and orientation. • A highly controlled and reproducible method is established. • A mechanism for growth and the role of ionic additives is proposed

Development and application of a system analysis code for liquid fueled molten salt reactors based on RELAP5 code

Energy Technology Data Exchange (ETDEWEB)

Shi, Chengbin [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Cheng, Maosong, E-mail: mscheng@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Liu, Guimin [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

2016-08-15

Highlights: • New point kinetics and thermo-hydraulics models as well as a numerical method are added into RELAP5 code to be suitable for liquid fueled molten salt reactor. • The extended REALP5 code is verified by the experimental benchmarks of MSRE. • The different transient scenarios of the MSBR are simulated to evaluate performance during the transients. - Abstract: The molten salt reactor (MSR) is one of the six advanced reactor concepts declared by the Generation IV International Forum (GIF), which can be characterized by attractive attributes as inherent safety, economical efficiency, natural resource protection, sustainable development and nuclear non-proliferation. It is important to make system safety analysis for nuclear power plant of MSR. In this paper, in order to developing a system analysis code suitable for liquid fueled molten salt reactors, the point kinetics and thermo-hydraulic models as well as the numerical method in thermal–hydraulic transient code Reactor Excursion and Leak Analysis Program (RELAP5) developed at the Idaho National Engineering Laboratory (INEL) for the U.S. Nuclear Regulatory Commission (NRC) are extended and verified by Molten Salt Reactor Experiment (MSRE) experimental benchmarks. And then, four transient scenarios including the load demand change, the primary flow transient, the secondary flow transient and the reactivity transient of the Molten Salt Breeder Reactor (MSBR) are modeled and simulated so as to evaluate the performance of the reactor during the anticipated transient events using the extended RELAP5 code. The results indicate the extended RELAP5 code is effective and well suited to the liquid fueled molten salt reactor, and the MSBR has strong inherent safety characteristics because of its large negative reactivity coefficient. In the future, the extended RELAP5 code will be used to perform transient safety analysis for a liquid fueled thorium molten salt reactor named TMSR-LF developed by the Center

Development and application of a system analysis code for liquid fueled molten salt reactors based on RELAP5 code

International Nuclear Information System (INIS)

Shi, Chengbin; Cheng, Maosong; Liu, Guimin

2016-01-01

Highlights: • New point kinetics and thermo-hydraulics models as well as a numerical method are added into RELAP5 code to be suitable for liquid fueled molten salt reactor. • The extended REALP5 code is verified by the experimental benchmarks of MSRE. • The different transient scenarios of the MSBR are simulated to evaluate performance during the transients. - Abstract: The molten salt reactor (MSR) is one of the six advanced reactor concepts declared by the Generation IV International Forum (GIF), which can be characterized by attractive attributes as inherent safety, economical efficiency, natural resource protection, sustainable development and nuclear non-proliferation. It is important to make system safety analysis for nuclear power plant of MSR. In this paper, in order to developing a system analysis code suitable for liquid fueled molten salt reactors, the point kinetics and thermo-hydraulic models as well as the numerical method in thermal–hydraulic transient code Reactor Excursion and Leak Analysis Program (RELAP5) developed at the Idaho National Engineering Laboratory (INEL) for the U.S. Nuclear Regulatory Commission (NRC) are extended and verified by Molten Salt Reactor Experiment (MSRE) experimental benchmarks. And then, four transient scenarios including the load demand change, the primary flow transient, the secondary flow transient and the reactivity transient of the Molten Salt Breeder Reactor (MSBR) are modeled and simulated so as to evaluate the performance of the reactor during the anticipated transient events using the extended RELAP5 code. The results indicate the extended RELAP5 code is effective and well suited to the liquid fueled molten salt reactor, and the MSBR has strong inherent safety characteristics because of its large negative reactivity coefficient. In the future, the extended RELAP5 code will be used to perform transient safety analysis for a liquid fueled thorium molten salt reactor named TMSR-LF developed by the Center

Phase transition of KCl under shock compression

CERN Document Server

Mashimo, T; Tsumoto, K; Zhang, Y; Ando, S; Tonda, H

2002-01-01

It had been reported that for potassium chloride (KCl) the B1-B2 phase transition (PT) occurs under shock and static compressions, but the measured transition points showed large scatter. In this study, Hugoniot measurement experiments were performed on KCl single crystals by the inclined-mirror method combined with use of a powder gun. The anisotropic Hugoniot elastic limits and PT points were observed. The PT points along the (100), (110) and (111) axis directions were determined as 2.5, 2.2 and 2.1 GPa, respectively. The anisotropic transition was reasonably explained in terms of the displacement mechanism along the (111) axis direction.

Computer simulation on molten ionic salts

International Nuclear Information System (INIS)

Kawamura, K.; Okada, I.

1978-01-01

The extensive advances in computer technology have since made it possible to apply computer simulation to the evaluation of the macroscopic and microscopic properties of molten salts. The evaluation of the potential energy in molten salts systems is complicated by the presence of long-range energy, i.e. Coulomb energy, in contrast to simple liquids where the potential energy is easily evaluated. It has been shown, however, that no difficulties are encountered when the Ewald method is applied to the evaluation of Coulomb energy. After a number of attempts had been made to approximate the pair potential, the Huggins-Mayer potential based on ionic crystals became the most often employed. Since it is thought that the only appreciable contribution to many-body potential, not included in Huggins-Mayer potential, arises from the internal electrostatic polarization of ions in molten ionic salts, computer simulation with a provision for ion polarization has been tried recently. The computations, which are employed mainly for molten alkali halides, can provide: (1) thermodynamic data such as internal energy, internal pressure and isothermal compressibility; (2) microscopic configurational data such as radial distribution functions; (3) transport data such as the diffusion coefficient and electrical conductivity; and (4) spectroscopic data such as the intensity of inelastic scattering and the stretching frequency of simple molecules. The computed results seem to agree well with the measured results. Computer simulation can also be used to test the effectiveness of a proposed pair potential and the adequacy of postulated models of molten salts, and to obtain experimentally inaccessible data. A further application of MD computation employing the pair potential based on an ionic model to BeF 2 , ZnCl 2 and SiO 2 shows the possibility of quantitative interpretation of structures and glass transformation phenomena

Design report on SCDAP/RELAP5 model improvements - debris bed and molten pool behavior

International Nuclear Information System (INIS)

Allison, C.M.; Rempe, J.L.; Chavez, S.A.

1994-11-01

The SCDAP/RELAP5/MOD3 computer code is designed to describe the overall reactor coolant system thermal-hydraulic response, core damage progression, and in combination with VICTORIA, fission product release and transport during severe accidents. Improvements for existing debris bed and molten pool models in the SCDAP/RELAP5/MOD3.1 code are described in this report. Model improvements to address (a) debris bed formation, heating, and melting; (b) molten pool formation and growth; and (c) molten pool crust failure are discussed. Relevant data, existing models, proposed modeling changes, and the anticipated impact of the changes are discussed. Recommendations for the assessment of improved models are provided

Waste treatment using molten salt oxidation

International Nuclear Information System (INIS)

Navratil, J.D.; Stewart, A.E.

1996-01-01

MSO technology can be characterized as a submerged oxidation process; the basic concept is to introduce air and wastes into a bed of molten salt, oxidize the organic wastes in the molten salt, use the heat of oxidation to keep the salt molten and remove the salt for disposal or processing and recycling. The molten salt (usually sodium carbonate at 900-1000 C) provides four waste management functions: providing a heat transfer medium, catalyzing the oxidation reaction, preventing the formation of acid gases by forming stable salts, and efficiently capturing ash particles and radioactive materials by the combined effects of wetting, encapsulation and dissolution. The MSO process requires no wet scrubbing system for off-gas treatment. The process has been developed through bench-scale and pilot-scale testing, with successful destruction demonstration of a wide variety of hazardous and mixed (radioactive and hazardous wastes). (author). 24 refs, 2 tabs, 2 figs

Demineralisation of a semianthracite char with molten salts/HCl

International Nuclear Information System (INIS)

Alfaro-Dominguez, M.; Sanchez Bajo, F.

2006-01-01

The effects of chemical heat treatments of a semianthracite char (AC) on the composition of the mineral fraction of the material are investigated. The starting char was first treated with a mixture of LiCl/KCl or LiCl/KCl/CaO at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. A small fraction of these samples were treated with 10 -3 M HCl solution. The composition changes were studied by X-ray diffraction. The predominant mineral components initially present in the starting char are quartz, mullite, muscovite and/or kaolinite and oldhamite. The treatments of AC resulted in significant changes in the mineral fraction of the material, in particular when LiCl/KCl/CaO was used. In this case, spurrite, γ-calcium orthosilicate and gehlenite were formed, which were eliminated by treatment with 10 -3 M HCl solution

Demineralisation of a semianthracite char with molten salts/HCl

Energy Technology Data Exchange (ETDEWEB)

Alfaro-Dominguez, M. [Departamento de Electronica e Ingenieria Electromecanica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz (Spain)]. E-mail: malfaro@unex.es; Sanchez Bajo, F. [Departamento de Electronica e Ingenieria Electromecanica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz (Spain)

2006-06-30

The effects of chemical heat treatments of a semianthracite char (AC) on the composition of the mineral fraction of the material are investigated. The starting char was first treated with a mixture of LiCl/KCl or LiCl/KCl/CaO at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. A small fraction of these samples were treated with 10{sup -3} M HCl solution. The composition changes were studied by X-ray diffraction. The predominant mineral components initially present in the starting char are quartz, mullite, muscovite and/or kaolinite and oldhamite. The treatments of AC resulted in significant changes in the mineral fraction of the material, in particular when LiCl/KCl/CaO was used. In this case, spurrite, {gamma}-calcium orthosilicate and gehlenite were formed, which were eliminated by treatment with 10{sup -3} M HCl solution.

Molten Salt Test Loop (MSTL) system customer interface document.

Energy Technology Data Exchange (ETDEWEB)

Gill, David Dennis; Kolb, William J.; Briggs, Ronald D.

2013-09-01

The National Solar Thermal Test Facility at Sandia National Laboratories has a unique test capability called the Molten Salt Test Loop (MSTL) system. MSTL is a test capability that allows customers and researchers to test components in flowing, molten nitrate salt. The components tested can range from materials samples, to individual components such as flex hoses, ball joints, and valves, up to full solar collecting systems such as central receiver panels, parabolic troughs, or linear Fresnel systems. MSTL provides realistic conditions similar to a portion of a concentrating solar power facility. The facility currently uses 60/40 nitrate %E2%80%9Csolar salt%E2%80%9D and can circulate the salt at pressure up to 40 bar (600psi), temperature to 585%C2%B0C, and flow rate of 44-50kg/s(400-600GPM) depending on temperature. The purpose of this document is to provide a basis for customers to evaluate the applicability to their testing needs, and to provide an outline of expectations for conducting testing on MSTL. The document can serve as the basis for testing agreements including Work for Others (WFO) and Cooperative Research and Development Agreements (CRADA). While this document provides the basis for these agreements and describes some of the requirements for testing using MSTL and on the site at Sandia, the document is not sufficient by itself as a test agreement. The document, however, does provide customers with a uniform set of information to begin the test planning process.

Thermodynamics investigation of a solar power system integrated oil and molten salt as heat transfer fluids

International Nuclear Information System (INIS)

Liu, Qibin; Bai, Zhang; Sun, Jie; Yan, Yuejun; Gao, Zhichao; Jin, Hongguang

2016-01-01

Highlights: • A new concentrating solar power system with a dual-solar field is proposed. • The superheated steam with more than 773 K is produced. • The performances of the proposed system are demonstrated. • The economic feasibility of the proposed system is validated. - Abstract: In this paper, a new parabolic trough solar power system that incorporates a dual-solar field with oil and molten salt as heat transfer fluids (HTFs) is proposed to effectively utilize the solar energy. The oil is chosen as a HTF in the low temperature solar field to heat the feeding water, and the high temperature solar field uses molten salt to superheat the steam that the temperature is higher than 773 K. The produced superheated steam enters a steam turbine to generate power. Energy analysis and exergy analysis of the system are implemented to evaluate the feasibility of the proposed system. Under considerations of variations of solar irradiation, the on-design and off-design thermodynamic performances of the system and the characteristics are investigated. The annual average solar-to-electric efficiency and the nominal efficiency under the given condition for the proposed solar thermal power generation system reach to 15.86% and 22.80%, which are higher than the reference system with a single HTF. The exergy losses within the solar heat transfer process of the proposed system are reduced by 7.8% and 45.23% compared with the solar power thermal systems using oil and molten salt as HTFs, respectively. The integrated approach with oil and molten salt as HTFs can make full use of the different physical properties of the HTFs, and optimize the heat transfer process between the HTFs and the water/steam. The exergy loss in the water evaporation and superheated process are reduced, the system efficiency and the economic performance are improved. The research findings provide a new approach for the improvement of the performances of solar thermal power plants.

Simplified Reference Electrode for Electrorefining of Spent Nuclear Fuel in High Temperature Molten Salt

Energy Technology Data Exchange (ETDEWEB)

Kim Davies; Shelly X Li

2007-09-01

Pyrochemical processing plays an important role in development of proliferation- resistant nuclear fuel cycles. At the Idaho National Laboratory (INL), a pyrochemical process has been implemented for the treatment of spent fuel from the Experimental Breeder Reactor II (EBR-II) in the last decade. Electrorefining in a high temperature molten salt is considered a signature or central technology in pyroprocessing fuel cycles. Separation of actinides from fission products is being demonstrated by electrorefining the spent fuel in a molten UCl3-LiCl-KCl electrolyte in two engineering scale electrorefiners (ERs). The electrorefining process is current controlled. The reference electrode provides process information through monitoring of the voltage difference between the reference and the anode and cathode electrodes. This information is essential for monitoring the reactions occurring at the electrodes, investigating separation efficiency, controlling the process rate, and determining the process end-point. The original reference electrode has provided good life expectancy and signal stability, but is not easily replaceable. The reference electrode used a vycor-glass ion-permeable membrane containing a high purity silver wire with one end positioned in ~2 grams of LiCl/KCl salt electrolyte with a low concentration (~1%) AgCl. It was, however, a complex assembly requiring specialized skill and talent to fabricate. The construction involved multiple small pieces, glass joints, ceramic to glass joints, and ceramic to metal joints all assembled in a high purity inert gas environment. As original electrodes reached end-of-life it was uncertain if the skills and knowledge were readily available to successfully fabricate replacements. Experimental work has been conducted to identify a simpler electrode design while retaining the needed long life and signal stability. This improved design, based on an ion-permeable membrane of mullite has been completed. Use of the silver wire

Simplified Reference Electrode for Electrorefining of Spent Nuclear Fuel in High Temperature Molten Salt

International Nuclear Information System (INIS)

Kim Davies; Shelly X Li

2007-01-01

Pyrochemical processing plays an important role in development of proliferation-resistant nuclear fuel cycles. At the Idaho National Laboratory (INL), a pyrochemical process has been implemented for the treatment of spent fuel from the Experimental Breeder Reactor II (EBR-II) in the last decade. Electrorefining in a high temperature molten salt is considered a signature or central technology in pyroprocessing fuel cycles. Separation of actinides from fission products is being demonstrated by electrorefining the spent fuel in a molten UCl3-LiCl-KCl electrolyte in two engineering scale electrorefiners (ERs). The electrorefining process is current controlled. The reference electrode provides process information through monitoring of the voltage difference between the reference and the anode and cathode electrodes. This information is essential for monitoring the reactions occurring at the electrodes, investigating separation efficiency, controlling the process rate, and determining the process end-point. The original reference electrode has provided good life expectancy and signal stability, but is not easily replaceable. The reference electrode used a vycor-glass ion-permeable membrane containing a high purity silver wire with one end positioned in ∼2 grams of LiCl/KCl salt electrolyte with a low concentration (∼1%) AgCl. It was, however, a complex assembly requiring specialized skill and talent to fabricate. The construction involved multiple small pieces, glass joints, ceramic to glass joints, and ceramic to metal joints all assembled in a high purity inert gas environment. As original electrodes reached end-of-life it was uncertain if the skills and knowledge were readily available to successfully fabricate replacements. Experimental work has been conducted to identify a simpler electrode design while retaining the needed long life and signal stability. This improved design, based on an ion-permeable membrane of mullite has been completed. Use of the silver

Numerical Analyses of a single-phase natural convection system for Molten Flibe using MARS-FLIBE code

Energy Technology Data Exchange (ETDEWEB)

Kang, Sarah; Bang, In Cheol [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

2014-10-15

These advantages make the MSR attractive and to be one of the six candidates for the Generation IV Reactor. Therefore, the researches related to the MSR are being conducted. To analyze the molten salt-cooled systems in the laboratory, this study generated the properties of molten salt using MARS-LMR. In this research, the implemented salts were Flibe (LiF-BeF{sub 2}) in a molar mixture that is 66% LiF and 34% BeF{sub 2}, respectively. Table 1 indicates the comparison of thermal properties of various coolants in nuclear power plants. Molten salt was added to the MARS-LMR code to support the analysis of Flibe-cooled systems. The molten salt includes LiF-BeF{sub 2} in a molar mixture that is 66% LiF and 34% BeF{sub 2}, respectively. MARS-LMR code for liquid metals uses the soft sphere model based on Monte Carlo calculations for particles interacting with pair potentials. Although MARS was originally intended for a safety analysis of light water reactor, Flibe properties were newly added to this code as so-called MARS-FLIBE which is applicable for Flibe-cooled systems. By using this thermodynamic property table file, the thermal hydraulic systems of Flibe can be simulated for numerical and parametric studies. In this study, the natural convection phenomena in the rectangular natural convection loop and IVR-ERVC in APR 1400 were simulated. Through the simulations in Flibe-cooled systems, the temperature distribution and mass flowrate of Flibe can be calculated and the heat transfer coefficients of Flibe in natural convection loop will be calculated by adding the related heat transfer correlations in the MARS-FLIBE code. MARS-FLIBE code will be used to predict and design of Flibe-cooled systems.

Hemispherand-Strapped Calix[4]pyrrole: An Ion-pair Receptor for the Recognition and Extraction of Lithium Nitrite.

Science.gov (United States)

He, Qing; Zhang, Zhan; Brewster, James T; Lynch, Vincent M; Kim, Sung Kuk; Sessler, Jonathan L

2016-08-10

The hemispherand-strapped calix[4]pyrrole (1) acts as an ion pair receptor that exhibits selectivity for lithium salts. In organic media (CD2Cl2 and CD3OD, v/v, 9:1), receptor 1 binds LiCl with high preference relative to NaCl, KCl, and RbCl. DFT calculations provided support for the observed selectivity. Single crystal structures of five different lithium ion-pair complexes of 1 were obtained. In the case of LiCl, a single bridging water molecule between the lithium cation and chloride anion was observed, while tight contact ion pairs were observed in the case of the LiBr, LiI, LiNO3, and LiNO2 salts. Receptor 1 proved effective as an extractant for LiNO2 under both model solid-liquid and liquid-liquid extraction conditions.

Molten salt breeder reactor

International Nuclear Information System (INIS)

1977-01-01

MSBR Study Group formed in October 1974 has studied molten salt breeder reactor and its various aspects. Usage of a molten salt fuel, extremely interesting as reactor chemistry, is a great feature to MSBR; there is no need for separate fuel making, reprocessing, waste storage facilities. The group studied the following, and these results are presented: molten salt technology, molten salt fuel chemistry and reprocessing, reactor characteristics, economy, reactor structural materials, etc. (Mori, K.)

Acidity of cations and the solubility of oxides in the eutectic KCl-LiCl melt at 700 Deg C

International Nuclear Information System (INIS)

Cherginets, V.L.; Rebrova, T.P.

1999-01-01

Products of MgO, NiO and CoO solubility in KCl-LiCl melt at 700 Deg C were determined by the method of potentiometric titration using Pt(O 2 )IZrO 2 (Y 2 O 3 ) membrane oxygen electrode. It was ascertained that acid properties of Cd 2+ and Pb'2 + cations are levelled to Li + properties, a break in E-pO graduation dependence in KCl-LiCl melt was observed at pO ∼ 2. Increase in oxides solubility in the melt studied compared with KCl-NaCl and CsCl-KCl-NaCl melts stems from the presence of Li + cations in the melt studied, which possess stronger acid properties than those of Na + or K + [ru

Transfer characteristics of a lithium chloride–potassium chloride molten salt

Directory of Open Access Journals (Sweden)

Eve Mullen

2017-12-01

Full Text Available Pyroprocessing is an alternative method of reprocessing spent fuel, usually involving the dissolving spent fuel in a molten salt media. The National Nuclear Laboratory designed, built, and commissioned a molten salt dynamics rig to investigate the transfer characteristics of molten lithium chloride–potassium chloride eutectic salt. The efficacy and flow characteristics of a high-temperature centrifugal pump and argon gas lift were obtained for pumping the molten salt at temperatures up to 500°C. The rig design proved suitable on an industrial scale and transfer methods appropriate for use in future molten salt systems. Corrosion within the rig was managed, and melting techniques were optimized to reduce stresses on the rig. The results obtained improve the understanding of molten salt transport dynamics, materials, and engineering design issues and support the industrialization of molten salts pyroprocessing.

Fabrication and oxidation resistance of titanium carbide-coated carbon fibres by reacting titanium hydride with carbon fibres in molten salts

International Nuclear Information System (INIS)

Dong, Z.J.; Li, X.K.; Yuan, G.M.; Cong, Y.; Li, N.; Jiang, Z.Y.; Hu, Z.J.

2009-01-01

Using carbon fibres and titanium hydride as a reactive carbon source and a metal source, respectively, a protective titanium carbide (TiC) coating was formed on carbon fibres in molten salts, composed of LiCl-KCl-KF, at 750-950 o C. The structure and morphology of the TiC coatings were characterised by X-ray diffraction and scanning electron microscopy, respectively. The oxidation resistance of the TiC-coated carbon fibres was measured by thermogravimetric analysis. The results reveal that control of the coating thickness is very important for improvement of the oxidation resistance of TiC-coated carbon fibres. The oxidative weight loss initiation temperature for the TiC-coated carbon fibres increases significantly when an appropriate coating thickness is used. However, thicker coatings lead to a decrease of the carbon fibres' weight loss initiation temperature due to the formation of cracks in the coating. The TiC coating thickness on carbon fibres can be controlled by adjusting the reaction temperature and time of the molten salt synthesis.

Preparation and Humidity Sensing Properties of KCl/MCM-41 Composite

International Nuclear Information System (INIS)

Li, Liu; Lian-Yuan, Wang; Wei, Li; Li-Ying, Kou; Zhi-Cheng, Zhong; Li-Fang, Liu

2010-01-01

KCl/mobil composition of matter-41 (MCM-41) composite has been synthesized via a heat-treating process and characterized by x-ray diffraction, high resolution transmission electron microscopy, and nitrogen adsorption/desorption isotherms. In contrast with pure MCM-41, KCl/MCM-41 composite exhibits improved humidity sensing properties within the relative humidity range of 11–95%. The impedance of KCl/MCM-41 composite changes by about four orders of magnitude over the whole humidity range with the response time and the recovery times are about 30 s and 35 s, respectively. Small humidity hysteresis and good stability are also observed based on our product. These results make our product a good candidate in fabricating humidity sensors with high performances and low synthetic complexity

Dynamic Network Reconstruction from Gene Expression Data Describing the Effect of LiCl Stimulation on Hepatocytes

Directory of Open Access Journals (Sweden)

Zellmer Sebastian

2005-12-01

Full Text Available Wnt/β-catenin signalling plays an important role in zonation of liver parenchyma and in patterning of hepatocyte heterogeneity. A characteristic marker of this heterogeneity is glutamine synthetase, which is expressed only in a subset of pericentrally located hepatocytes. To investigate, whether and how the Wnt/β-catenin signalling pathway is involved a culture of hepatocytes was stimulated by LiCl. This resulted in an increase in the specific GS activity, indicating that the Wnt/β-catenin pathway may participate in regulating GS levels. Affymetrix GeneChip oligonucleotide arrays were used to monitor the gene expression changes during a period from 2 to 24 hours after stimulation by LiCl. Samples from a cultivation without stimulation were used as controls. Based on the gene expression profiles a hypothetic signal transduction network was constructed by a reverse engineering algorithm. The network robustness was tested and the most stable structure was identified.

INTERACTION OF LASER RADIATION WITH MATTER: Influence of Ca and Pb impurities on the bulk optical strength of ultrapure NaCl and KCl crystals

Science.gov (United States)

Vinogradov, An V.; Voszka, R.; Kovalev, Valerii I.; Faĭzullov, F. S.; Janszky, J.

1987-06-01

A significant increase (by a factor of about 3) of the bulk damage threshold in the case of interaction of CO2 laser radiation pulses with ultrapure NaCl and KCl crystals grown in a reactive atmosphere was observed on introduction of divalent metal ions Ca and Pb in concentrations of 10-5-10-6 mol/mol. Impurities were introduced in concentrations of 10-8-10-3 and 2×10-7-10-4 mol/mol into the melts of KCl and NaCl, respectively. The concentration of other impurities (including OH) did not exceed ~10-6 mol/mol. A physical model was developed to account for the observed dependence on the basis of an analogy between a system of colloidal particles and F centers in a crystal and a liquid-vapor system.

Synthesis of Bi{sub 25}FeO{sub 39} by molten salts method and its Mössbauer spectrum

Energy Technology Data Exchange (ETDEWEB)

Flores Morales, Shirley Saraí; León Flores, Jesús A.; Pérez Mazariego, José Luis, E-mail: mazariego@ciencias.unam.mx; Marquina Fábrega, Vivianne; Gómez González, Raúl W.

2017-01-01

A sample of Bi{sub 25}FeO{sub 39} was synthesized by the molten salts method in 2 h at 750 °C with KCl-KBr as reaction media. The sample was characterized with X-ray powder diffraction and Mössbauer spectroscopy. The Rietveld refinement of the X-ray diffraction confirms that a sillenite type structure with a cell parameter a=10.190(4) Å was achieved, with only small traces of Bi{sub 2}O{sub 3}. In order to get a Mössbauer spectrum with a good signal to noise ratio, the synthesis was made using 95% enriched α–{sup 57}Fe{sub 2}O{sub 3}. To our knowledge, this is the first time that a Mössbauer spectrum for the Bi{sub 25}FeO{sub 39} has been recorded. The nonappearance of a magnetic sextet confirms its paramagnetic behavior. The measured Mössbauer parameters (IS=0.20±0.004 mm/s and QS=0.2±0.07 mm/s) correspond to Fe{sup +3} in very symmetric surroundings, and rule out some interpretations given to the doublet observed in some Mössbauer spectra of BiFeO{sub 3}.

Lewis-Acid/Base Effects on Gallium Volatility in Molten Chlorides

International Nuclear Information System (INIS)

Williams, D.F.

2001-01-01

It has been proposed that GaCl 3 can be removed by direct volatilization from a Pu-Ga alloy that is dissolved in a molten chloride salt. Although pure GaCl 3 is quite volatile (boiling point, 201 C), the behavior of GaCl 3 dissolved in chloride salts is different due to solution effects and is critically dependent on the composition of the solvent salt (i.e., its Lewis-acid/base character). In this report, the behavior of gallium in prototypical Lewis-acid and Lewis-base salts is compared. It was found that gallium volatility is suppressed in basic melts and enhanced in acidic melts. The implications of these results on the potential for simple gallium removal in molten salt systems are significant

Hydrothermal preparation of zeolite Li-A and ion exchange properties of Cs and Sr in salt waste

International Nuclear Information System (INIS)

Lee, S. H.; Kim, J. G.; Lee, J. H.; Kim, J. H.

2005-01-01

An advanced spent fuel management process that were based on Li reduction of the oxide spent fuel to a metallic form will generate a LiCl waste. Zeolite A has been reported as a promising immobilization medium for waste salt with CsCl and SrCl 2 . However, Sodium is accumulated as an ionic form (Na + -ion) in molten salt during ion exchange step between Na + -ion in zeolite A and Li + -ion in the molten salt. Therefore, zeolite Na-A need to be replaced by the Li-type zeolite for recycling the salt waste by removing the Cs and Sr ions. In this study, the hydrothermal preparation of zeolite Li-A was performed in 350ml pressure vessel by P. Norby method. The preparation characteristics of zeolite Li-A was investigated. And the ion exchange properties of Cs and Sr in molten LiCl salt were investigated under the condition of 923K using zeolite 4A and prepared zeolite Li-A

Fiscal 1976 Sunshine Project result report. R and D on solar heat power generation system (R and D on curved reflector light collection system); 1976 nendo taiyonetsu hatsuden system no kenkyu kaihatsu seika hokokusho. Kyokumen shuko hoshiki system no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

As a part of Sunshine Project, study was made on the solar heat power generation system using a solar collection system composed of plane and curved reflectors. In fiscal 1976, study was made on plant characteristics and plant operation by using system simulation program, and the concept design of the system was promoted. The reflectance of the plane reflector was improved up to 0.92 by remodeling the prototype collector fabricated in last fiscal year, and the prototype test facility of full-scale reflectors for 1,000kW solar power plant was prepared to obtain design data for large reflectors. The prototype heat collection loop control equipment which was prepared to simulate control of plant operation conditions according to solar radiation fluctuation, succeeded in prediction of solar radiation fluctuation within nearly 30min. New study was also made on a system using both accumulator and molten salt heat storage equipment, and each proper capacity for power plants was determined. In addition, high-temperature vapor generation for 2 hours was achieved by the prototype heat storage equipment using KCl-LiCl molten salt. (NEDO)

An Investigation on the Thermophysical Properties of a Binary Molten Salt System Containing Both Aluminum Oxide and Titanium Oxide Nanoparticle Suspensions

Science.gov (United States)

Giridhar, Kunal

Molten salts are showing great potential to replace current heat transfer and thermal energy storage fluids in concentrated solar plants because of their capability to maximize thermal energy storage, greater stability, cost effectiveness and significant thermal properties. However one of the major drawbacks of using molten salt as heat transfer fluid is that they are in solid state at room temperature and they have a high freezing point. Hence, significant resources would be required to maintain it in liquid form. If molten salt freezes while in operation, it would eventually damage piping network due to its volume shrinkage along with rendering the entire plant inoperable. It is long known that addition of nanoparticle suspensions has led to significant changes in thermal properties of fluids. In this investigation, aluminum oxide and titanium oxide nanoparticles of varying concentrations are added to molten salt/solar salt system consisting of 60% sodium nitrate and 40% potassium nitrate. Using differential scanning calorimeter, an attempt will be made to investigate changes in heat capacity of system, depression in freezing point and changes in latent heat of fusion. Scanning electron microscope will be used to take images of samples to study changes in micro-structure of mixture, ensure uniform distribution of nanoparticle in system and verify authenticity of materials used for experimentation. Due to enormous magnitude of CSP plant, actual implementation of molten salt system is on a large scale. With this investigation, even microscopic enhancement in heat capacity and slight lowering of freezing point will lead to greater benefits in terms of efficiency and cost of operation of plant. These results will further the argument for viability of molten salt as a heat transfer fluid and thermal storage system in CSP. One of the objective of this experimentation is to also collect experimental data which can be used for establishing relation between concentration

Release of mercury halides from KCl denuders in the presence of ozone

Directory of Open Access Journals (Sweden)

S. N. Lyman

2010-09-01

Full Text Available KCl-coated denuders have become a standard method for measurement of gaseous oxidized mercury, but their performance has not been exhaustively evaluated, especially in field conditions. In this study, KCl-coated and uncoated quartz denuders loaded with HgCl₂ and HgBr₂ lost 29–55% of these compounds, apparently as elemental mercury, when exposed to ozone (range of 6–100 ppb tested. This effect was also observed for denuders loaded with gaseous oxidized mercury at a field site in Nevada (3–37% of oxidized mercury lost. In addition, collection efficiency decreased by 12–30% for denuders exposed to 50 ppb ozone during collection of HgCl₂. While data presented were obtained from laboratory tests and as such do not exactly simulate field sampling conditions, these results indicate that the KCl denuder oxidized mercury collection method may not be as robust as previously thought. This work highlights needs for further testing of this method, clear identification of gaseous oxidized mercury compounds in the atmosphere, and development of field calibration methods for these compounds.

Implementation of Molten Salt Properties into RELAP5-3D/ATHENA

International Nuclear Information System (INIS)

Cliff Davis

2005-01-01

Molten salts are being considered as coolants for the Next Generation Nuclear Plant (NGNP) in both the reactor and the heat transport loop between the reactor and the hydrogen production plant because of their superior thermophysical properties compared to helium. Because specific molten salts have not been selected for either application, four separate molten salts were implemented into the RELAP5-3D/ATHENA computer program as working fluids. The implemented salts were LiF-BeF2 in a molar mixture that is 66% LiF and 34% BeF2, respectively, NaBF4-NaF (92% and 8%), LiF-NaF-KF (11.5%, 46.5%, and 42%), and NaF-ZrF4 (50% and 50%). LiF-BeF2 is currently the first choice for the primary coolant for the Advanced High-Temperature Reactor, while NaF-ZrF4 is being considered as an alternate. NaBF4-NaF and LiFNaF-KF are being considered as possible coolants for the heat transport loop. The molten salts were implemented into ATHENA using a simplified equation of state based on data and correlations obtained from Oak Ridge National Laboratory. The simplified equation of state assumes that the liquid density is a function of temperature and pressure and that the liquid heat capacity is constant. The vapor is assumed to have the same composition as the liquid and is assumed to be a perfect gas. The implementation of the thermodynamic properties into ATHENA for LiF-BeF2 was verified by comparisons with results from a detailed equation of state that utilized a soft-sphere model. The comparisons between the simplified and soft-sphere models were in reasonable agreement for liquid. The agreement for vapor properties was not nearly as good as that obtained for liquid. Large uncertainties are possible in the vapor properties because of a lack of experimental data. The simplified model used here is not expected to be accurate for boiling or single-phase vapor conditions. Because neither condition is expected during NGNP applications, the simplified equation of state is considered

A study on conductivity, density, and viscosity of molten salt systems

International Nuclear Information System (INIS)

Cho, Kangjo

1976-01-01

A relation between the equivalent conductivity and density for molten salts is deduced with the aid of significant structures theory, and the solid state density at melting point is evaluated approximately for some rare-earth metal chlorides and the other chlorides. Furthermore, the relation among the equivalent conductivity, density, and viscosity for some molten salts is discussed. (auth.)

Natural convection heat transfer in the molten metal pool

International Nuclear Information System (INIS)

Park, R.J.; Kim, S.B.; Kim, H.D.; Choi, S.M.

1997-01-01

Analytical studies using the FLOW-3D computer program have been performed on natural convection heat transfer of a high density molten metal pool, in order to evaluate the coolability of the corium pool. The FLOW-3D results on the temperature distribution and the heat transfer rate in the molten metal pool region have been compared and evaluated with the experimental data. The FLOW-3D results have shown that the developed natural convection flow contributes to the solidified crust formation of the high density molten metal pool. The present FLOW-3D results, on the relationship between the Nusselt number and the Rayleigh number in the molten metal pool region, are more similar to the calculated results of Globe and Dropkin's correlation than any others. The natural convection heat transfer in the low aspect ratio case is more substantial than that in the high aspect ratio case. The FLOW-3D results, on the temperature profile and on the heat transfer rate in the molten metal pool region, are very similar to the experimental data. The heat transfer rate of the internal heat generation case is higher than that of the bottom heating case at the same heat supply condition. (author)

A simple and rapid nucleic acid preparation method for reverse ...

African Journals Online (AJOL)

detergent (0.5% Triton XL-80 N) buffers, vortexed for 3 min and then 2.5 ìl of this aliquots was used in RT-PCR. Alternatively, evaluation of the efficiency of different buffers (sodium sulphite buffer, 0.1 M HCl, 0.1 M NaOH, 0.1 M Tris, 0.1 M EDTA, 0.1 M phosphate buffer, 0.1 M LiCl, 0.1 M KCl, 1 M NaCl and water (H2O)) was ...

The Characteristic of Molten Heat Salt Storage System Utilizing Solar Energy Combined with Valley Electric

Directory of Open Access Journals (Sweden)

LI .Jiu-ru

2017-02-01

Full Text Available With the environmental pollution and energy consumption clue to the large difference between peak and valley of power grid，the molten salt heat storage system(MSHSS utilizing solar Energy combined with valley electric is presented for good energy saving and low emissions. The costs of MSHSS utilizing solar Energy combined with valley electric are greatly reduced. The law of heat transfer in molten salt heat storage technology is studied with the method of grey correlation analysis. The results show the effect of elbow sizes on surface convective heat transfer coefficient with different flow velocities.

Molten-salt converter reactors

International Nuclear Information System (INIS)

Perry, A.M.

1975-01-01

Molten-salt reactors appear to have substantial promise as advanced converters. Conversion ratios of 0.85 to 0.9 should be attainable with favourable fuel cycle costs, with 235 U valued at $12/g. An increase in 235 U value by a factor of two or three ($10 to $30/lb. U 3 O 8 , $75/SWU) would be expected to increase the optimum conversion ratio, but this has not been analyzed in detail. The processing necessary to recover uranium from the fuel salt has been partially demonstrated in the MSRE. The equipment for doing this would be located at the reactor, and there would be no reliance on an established recycle industry. Processing costs are expected to be quite low, and fuel cycle optimization depends primarily on inventory and burnup or replacement costs for the fuel and for the carrier salt. Significant development problems remain to be resolved for molten-salt reactors, notably the control of tritium and the elimination of intergranular cracking of Hastelloy-N in contact with tellurium. However, these problems appear to be amenable to solution. It is appropriate to consider separating the development schedule for molten-salt reactors from that for the processing technology required for breeding. The Molten-Salt Converter Reactor should be a useful reactor in its own right and would be an advance towards the achievement of true breeding in thermal reactors. (author)

Reoxidation of uranium metal immersed in a Li{sub 2}O-LiCl molten salt after electrolytic reduction of uranium oxide

Energy Technology Data Exchange (ETDEWEB)

Choi, Eun-Young, E-mail: eychoi@kaeri.re.kr [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Jeon, Min Ku [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Department of Quantum Energy Chemical Engineering, University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113 (Korea, Republic of); Lee, Jeong [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Kim, Sung-Wook [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Department of Quantum Energy Chemical Engineering, University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113 (Korea, Republic of); Lee, Sang Kwon [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Lee, Sung-Jai [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of); Department of Quantum Energy Chemical Engineering, University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113 (Korea, Republic of); Heo, Dong Hyun; Kang, Hyun Woo; Jeon, Sang-Chae; Hur, Jin-Mok [Korea Atomic Energy Research Institute, Daedoek-daero 989-111, Yuseong-gu, Daejeon 34057 (Korea, Republic of)

2017-03-15

We present our findings that uranium (U) metal prepared by using the electrolytic reduction process for U oxide (UO{sub 2}) in a Li{sub 2}O–LiCl salt can be reoxidized into UO{sub 2} through the reaction between the U metal and Li{sub 2}O in LiCl. Two salt types were used for immersion of the U metal: one was the salt used for electrolytic reduction, and the other was applied to the unused LiCl salts with various concentrations of Li{sub 2}O and Li metal. Our results revealed that the degree of reoxidation increases with the increasing Li{sub 2}O concentration in LiCl and that the presence of the Li metal in LiCl suppresses the reoxidation of the U metal. - Highlights: • Uranium (U) metal can be reoxidized into UO{sub 2} through the reaction between the U metal and Li{sub 2}O in LiCl. • The degree of reoxidation increases with the Li{sub 2}O concentration in LiCl. • The presence of the Li metal in LiCl suppresses the reoxidation of the U metal.

Development of a three dimension multi-physics code for molten salt fast reactor

International Nuclear Information System (INIS)

Cheng Maosong; Dai Zhimin

2014-01-01

Molten Salt Reactor (MSR) was selected as one of the six innovative nuclear reactors by the Generation IV International Forum (GIF). The circulating-fuel in the can-type molten salt fast reactor makes the neutronics and thermo-hydraulics of the reactor strongly coupled and different from that of traditional solid-fuel reactors. In the present paper: a new coupling model is presented that physically describes the inherent relations between the neutron flux, the delayed neutron precursor, the heat transfer and the turbulent flow. Based on the model, integrating nuclear data processing, CAD modeling, structured and unstructured mesh technology, data analysis and visualization application, a three dimension steady state simulation code system (MSR3DS) for the can-type molten salt fast reactor is developed and validated. In order to demonstrate the ability of the code, the three dimension distributions of the velocity, the neutron flux, the delayed neutron precursor and the temperature were obtained for the simplified MOlten Salt Advanced Reactor Transmuter (MOSART) using this code. The results indicate that the MSR3DS code can provide a feasible description of multi-physical coupling phenomena in can-type molten salt fast reactor. Furthermore, the code can well predict the flow effect of fuel salt and the transport effect of the turbulent diffusion. (authors)

Partition of actinides and fission products between metal and molten salt phases: Theory, measurement, and application to IFR pyroprocess development

International Nuclear Information System (INIS)

Ackerman, J.P.; Johnson, T.R.

1993-01-01

The chemical basis of Integral Fast Reactor fuel reprocessing (pyroprocessing) is partition of fuel, cladding, and fission product elements between molten LiCl-KCl and either a solid metal phase or a liquid cadmium phase. The partition reactions are described herein, and the thermodynamic basis for predicting distributions of actinides and fission products in the pyroprocess is discussed. The critical role of metal-phase activity coefficients, especially those of rare earth and the transuranic elements, is described. Measured separation factors, which are analogous to equilibrium constants but which involve concentrations rather than activities, are presented. The uses of thermodynamic calculations in process development are described, as are computer codes developed for calculating material flows and phase compositions in pyroprocessing