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A binary pebble bed of lithium titanate (Li 2 TiO 3 ) was irradiated in the Japan Materials Testing Reactor (JMTR), and its tritium recovery characteristics bed was studied under pulsed neutron operations. The temperature at the outside edge of the pebble bed increased from 300 to 350 °C immediately after the window of hafnium (Hf) neutron absorber was turned toward the reactor core, while the tritium recovery rate increased gradually. The ratio of tritium recovery rate to generation rate at the high-power, ( R / G ) high , approached the saturated value of unity at about 20 h of operation. Overall tritium recovery behavior under the pulsed operation was similar to that under the steady state power operation. An estimated time constant of about 3 h for the tritium recovery was much longer than the thermal time constant of about 100 s.

Li 2 TiO 3 is one of the most promising candidate solid breeder materials. However, its structural properties have not been established, especially for a non-stoichiometric composition. In the present paper, non-stoichiometric compositions of Li 2 TiO 3 have been extensively investigated by means of thermogravimetry, X-ray diffraction and color change observations. For the Li 2 TiO 3 samples used in the present study, Li 2 CO 3 and TiO 2 powders were mixed in the proportion corresponding to the molecular ratio Li 2 O/TiO 2 of either 1.00, 0.95, 0.938, 0.90 or 0.80. In thermogravimetry, mass of the Li 2 TiO 3 samples was found to decrease with time in a hydrogen atmosphere, then to increase after the change of the atmosphere from hydrogen to oxygen. The color of the samples was observed to change from white to dark blue under a hydrogen atmosphere. These results suggest not only oxygen deficient but also Li 2 O deficient defect formation. Thus, the doubly non-stoichiometric composition, Li 2− x TiO 3− y , has been confirmed.

The atmosphere controlled high temperature mass spectrometer has provided the vapor pressure data for a promising tritium breeding material, Li2TiO3, under condition of low-pressure hydrogen atmosphere. The observed vaporization behavior of Li2TiO3 under hydrogen addition is presented here. It was pointed out that hydrogen addition may cause formation of non-stoichiometric composition phase. For elucidating its possible non-stoichiometric character, the composition of Li2TiO3 has been investigated mainly by means of thermogravimetry. The results revealed that Li2TiO3 has doubly non-stoichiometric composition, Li2-xTiO3-y

Li 2 TiO 3 is among the most promising candidates for solid breeder materials. However, its structural property, especially the possibility of non-stoichiometric composition, has not been well established yet. Therefore, the composition of Li 2 TiO 3 has been further investigated by means of thermogravimetry, XRD etc. Also, thermal diffusivity measurement was carried out. Mass of Li 2 TiO 3 was found to change after the change of the atmosphere from hydrogen to oxygen as observed by means of thermogravimetry. At the same time, the color was observed to change from dark blue to initial color, white. These behaviors suggest not only oxygen deficient but also lithium oxide deficient defects formation. Thus, the doubly non-stoichiometric composition, Li 2− x TiO 3− y , has been confirmed. Further, it was shown by thermal diffusivity measurement that 95Li 2 TiO 3 (i.e. Li 2 O/TiO 2 =0.95) has a higher thermal conductivity than 100Li 2 TiO 3 .

Tritium needed as a fuel for fusion reactors is produced via neutron capture by lithium-6 (6Li). However, natural Li contains only about 7.8% 6Li, and enrichment of 6Li up to 90% is required for adequate tritium breeding in fusion reactors. The mercury amalgam method is superior to some of the lithium isotope enrichment methods. In Japan, lithium isotope enrichment methods have been developed to avoid the environmental hazards of using mercury. However, the isotope separation coefficient and efficiency is too low to meet the practical need of large mass production of 6Li. Therefore, new Li isotope separation technique using a Li ionic superconductor functioning as a Li isotope separation membrane (LISM) have been developed [1]. Li ions move by electrodialysis through LISM between the cathode and the anode in lithium solutions. Because the mobility of 6Li ions is higher than that of 7Li ions, 6Li can be enriched on the cathode side of a cell. It has been reported that the difference in the mobility between 6Li and 7Li become large in ionic superconductor. The isotope effect in ionic superconductor is expected to be applicable to isotope separation membrane. In this research, we numerically investigated the ionic mobility of Li isotopes in ionic superconductor. Combing the first principle and the kinetics Monte Calro simulation, we calculate the diffusion constant of 6Li and 7Li. I show the two important effects for the difference in the mobility between isotope of Li. The first is the quantum effect, which decrease the diffusion barrier for Li ion and increase the ratio of the diffusion constant of Li isotopes. The second is the correlation effect between 6Li, 7Li and vacancy. Using Li0.29La0.57TiO3 (LLTO) as the Li ionic superconductor was prepared, and the relationship between the 6Li separation coefficient and the electrodialysis time was investigated. After electrodialysis, we obtained a maximum of 1.04 for the 6Li isotope separation coefficient. This result showed that the 6Li isotope separation coefficient of this method is the same as that of the amalgamation process using mercury (1.06). Thus, this method has the potential to be a superior 6Li enrichment method to produce 90% enriched tritium breeder for fusion reactors. Figure 1

In recent years, the industrial importance of lithium (Li) has increased due to its use in Li-ion batteries. For example, large-sized Li-ion batteries are used as power supplies for electric vehicles and for storage of electricity in smart grids and smart houses. Therefore, a large amount of Li is required worldwide. The extraction of Li from used Li-ion batteries would allow a large amount of Li to be inexpensively acquired. The technology for recycling cobalt (Co) and nickel (Ni) from used Li-ion batteries has already been established. On the contrary, the technology for recycling Li from used Li-ion batteries is not yet established. I have developed a method for the recovery of Li from seawater using a Li ionic superconductor functioning as a Li-ion separation membrane (LISM) [1]. Only Li ions were successfully recovered from seawater through the LISM; other ions in the seawater did not permeate the membrane. Therefore, I have developed an innovative new method for recycling Li from used Li-ion batteries using the LISM. Figure shows the proposed Li recovery method. This innovative method involves the use of an LISM whereby only Li ions in a solution of used Li-ion batteries permeate from the positive electrode side to the negative electrode side during electrodialysis; the other ions, including Co, Al, and F, do not permeate the membrane. Li0.29La0.57TiO3 was selected as the LISM because it exhibits high durability against water. The positive side of the dialysis cell was filled with used Li-ion battery solution, supplied by DOWA ECO-SYSTEM Co., Ltd., Japan; the Li concentration of the solution was 2543.5 mg/L. Then the negative side was filled with distilled water. The applied dialysis voltage was 5 V, and electrode area was 16 cm2. The calculation of the Li recovery ratios for this first of a kind electrodialysis technique with an LISM sheet was performed. The Li recovery ratio increased with electrodialysis time, reaching approximately 10% at 72 h of dialysis. The recovery ratios of Co, Al, and F were not calculated because the concentrations of Co, Al, and F were below the detection limit of inductively coupled plasma atomic emission spectrometry (ICP-AES). After electrodialysis, CO2 gas was bubbled in the Li recovery water to produce lithium carbonate (Li2CO3) as a raw material for Li-ion batteries. The Li2CO3 deposition was easily generated by the reaction of CO2gas and the Li recovery solution as a lithium hydroxide (LiOH) solution. This new method for recycling Li-ion batteries shows good energy efficiency and is easily scalable. Thus, this electrodialysis method is suitable for the recovery of Li from used Li-ion batteries. [1] T. Hoshino, Desalination, 359, 59-63 (2015). Figure 1

Lithium (Li) is rapidly becoming a valuable commodity. In recent years, the industrial importance of Li has increased due to its use in Li-ion batteries. For example, large-sized Li-ion batteries are used as power supplies for electric vehicles and for storage of electricity in smart grids and smart houses. Therefore, a large amount of Li is required worldwide. Li reserves in the South American countries of Chile, Bolivia, and Argentina account for more than half of the world’s Li reserves; these countries have outstanding Li resources (brine water). Although Li extraction from chloride brine water is easy, the quantity of natural resources in these waters is limited. In contrast, the quantity of natural resources in sulfate brine water is large; however, the Li recovery technology from sulfate brine water has yet to be established. Thus, the extraction of Li from used Li-ion batteries would allow a large amount of Li to be inexpensively acquired. The technology for recycling cobalt (Co) and nickel (Ni) from used Li-ion batteries has already been established. On the contrary, the technology for recycling Li from used Li-ion batteries is not yet established, because the cost of Li recycling is higher than the import price of Li from South America. I have developed a method for the recovery of Li from seawater using a Li ionic superconductor functioning as a Li-ion separation membrane (LISM) [1]. Only Li ions were successfully recovered from seawater through the LISM; other ions in the seawater did not permeate the membrane. Therefore, I have developed an innovative new method for recycling Li from used Li-ion batteries using the LISM. Figure 1 shows the proposed Li recovery method. This innovative method involves the use of an LISM whereby only Li ions in a solution of used Li-ion batteries permeate from the positive electrode side to the negative electrode side during electrodialysis; the other ions, including Co, Al, and F, do not permeate the membrane. In this study, Li0.29La0.57TiO3 was selected as the LISM because it exhibits high durability against water. The area and thickness of the LISM are 25 cm2 (5.0 cm × 5.0 cm) and 0.5 mm, respectively. The positive side of the dialysis cell was filled with used Li-ion battery solution, supplied by DOWA ECO-SYSTEM Co., Ltd., Japan; the Li concentration of the solution was 2543.5 mg/L. Then the negative side was filled with distilled water. The applied dialysis voltage was 5 V, and the duration of dialysis was 72 h. The electrodes were Ti–Ir alloy on the positive electrode side and SUS316 on the negative electrode side, and electrode area was 16 cm2. The calculation of the Li recovery ratios for this first of a kind electrodialysis technique with an LISM sheet was performed. The Li recovery ratio increased with electrodialysis time, reaching approximately 10% at 72 h of dialysis. The recovery ratios of Co, Al, and F were not calculated because the concentrations of Co, Al, and F were below the detection limit of inductively coupled plasma atomic emission spectrometry (ICP-AES). Moreover, the Li concentration dependency of the Li recovery amount was measured. These measurements showed that the amount of Li in the recovery solution increased with the Li concentration of the used Li-ion battery solution. This indicates that a used Li-ion battery solution with high Li concentration enables good Li recovery efficiency by this method. After electrodialysis, CO2 gas was bubbled in the Li recovery water to produce lithium carbonate (Li2CO3) as a raw material for Li-ion batteries. The Li2CO3 deposition was easily generated by the reaction of CO2 gas and the Li recovery solution as a lithium hydroxide (LiOH) solution. This new method for recycling Li-ion batteries shows good energy efficiency and is easily scalable. Furthermore, the estimated cost of 1 kg Li2CO3 produced by this method is approximately $3. This value is lower than the import price of Li ($5 to $8) from South America. Thus, this electrodialysis method is suitable for the recovery of Li from used Li-ion batteries. Reference [1] T. Hoshino, Innovative lithium recovery technique from seawater by using world-first dialysis with a lithium ionic superconductor, Desalination, 359 (2015) 59-63. Figure 1

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Numerical computation of river flows have been employed the general coordinate system to adjust a river plane form. An adjustment flexibility of the coordinate system is better but it is difficult to generate a grid system in order to compute stably because grid system is not determined uniquely. This study develops a new boundary fitting method introducing the hierarchical quad-tree grid system in computation of shallow water equation. The numerical model with the quad-tree grid system apply to compute flow pattern in meandering channel, the result agree with experiments result well.

Lithium (Li) procurement is becoming a matter of importance worldwide. Herein, I propose a method for recovering Li from seawater by using world-first dialysis, wherein Li only permeates from the negative electrode side to the positive electrode side through a Li ionic superconductor functioning as a Li separation membrane (LISM). Measurements of the Li ion concentration at the positive electrode side as a function of dialysis duration showed that the Li recovery ratio increased to approximately 7% after 72 h with no applied electric voltage. Moreover, other ions in the seawater did not permeate the LISM. With both ends of the LISM bound with a negative and positive electrode, hydrated Li ion was transformed to Li ion only because Li ion can permeate through the LISM. This new recovery method shows good energy efficiency and is easily scalable and is thus suitable for the industrialised mass production of Li in South American countries, which have briny water containing Li.

As a part of the Broader Approach activities, R&D on blanket related materials, reduced-activation ferritic martensitic (RAFM) steels as a structural material, SiCf/SiC composites for flow channel insert in the liquid blanket and/or use as advanced structural material, advanced tritium breeders and neutron multiplier, has been initiated directed at DEMO. As part of the RAFM steel mass production development, a 5 ton heat of RAFM steel (F82H) was procured by Electra Slag Re-melting as the secondary melting method, which was effective in controlling unwanted impurities. An 11 ton heat of EUROFER was also produced. For the SiCf/SiC composite development, NITE- and CVI-SiCf/SiC composites were prepared as reference materials and preliminary mechanical and physical properties were measured. Also compatibility tests between SiC and Pb-17Li have been prepared, related to the He-cooled Li-Pb blanket concept. For the beryllide neutron multiplayer Be-Ti alloy development, large size rods of about 30 mm diameter were fabricated successfully in EU. (C) 2011 Elsevier B.V. All rights reserved.

The pebbles of Li2TiO3 with excess Li, which is in a developmental stage in JAEA (Japan Atomic Energy Agency) as an advanced tritium breeding material, were exposed to water vapor at elevated temperatures. In the temperature rising process from room temperature to 900 °C, pore distribution and BET surface area were largely changed. The surface area decreased gradually by a sintering effect when maintained at 900 °C for a long time. The release of water vapor was observed at about 450 °C by the decomposition of LiOH in addition to the release of adsorbed water at the beginning of heating. A large release peak of CO2 was observed at 700 °C. This is caused by the decomposition of Li2CO3. A remarkable melt layer was formed on the pebble surface over 700 °C by melting of Li2CO3. The change of pebble structure and the influences of LiOH and Li2CO3 have to be taken into account, when the release behavior of bred tritium from Li2TiO3 pebbles is discussed.