Lithium Ion Sieve Research Articles

Growth of β-Li2TiO3 Nanocrystals from LiCl and LiOH Fluxes

Lithium–titanium oxide (β-Li2TiO3, LTO) crystals are a requisite precursor for hydrated titanium oxide [TiO(OH)2 or H2TiO3, HTO], which is a promising lithium-ion (Li+) sieve because of its high theoretical Li+-exchange capacity (LiEC) and unique crystal structure. Herein, we report the flux growth of LTO nanocrystals from LiCl and LiOH as a function of the holding temperature. The use of LiCl as a flux resulted in the growth of single-phase, monodispersed LTO nanocrystals at ≥600 °C. On the other hand, using a LiOH flux led to the growth of single-phase LTO crystals at ≥550 °C. The surface areas of the LTO samples grown from the LiCl and LiOH fluxes, LTOLiCl and LTOLiOH, respectively, reached their respective maxima of 17 and 29 m2 g–1, which are 2–4 times the value (7 m2 g–1) obtained for the LTO synthesized via a solid-state reaction at 700 °C. The resulting LTO samples were then immersed in an acid to prepare the HTO samples as adsorbents for Li+. Isotherms of Li+ adsorption on the HTO samples showed ...

Application of citric acid as eluting medium for titanium type lithium ion sieve

The titanium type lithium ion sieve (Ti-LIS) is usually considered as a promising lithium ion sieve (LIS) by the virtue of its superiorities in both stable structure and high adsorption capacity. Acidification process is a significant and necessary step for LIS application in the lithium adsorption from brine, which has raised two problems including partly dissolution of the Ti-LIS structure and the low lithium ions enrichment in elution solutions. Many reported works about the Ti-LIS focused on reducing the amount of loss of Ti-LIS but ignored the lithium ions enrichment in elution solutions. In this manuscript, an effective strategy that employing a proper weak polyprotic acid to replace the most widely eluting medium of hydrochloric acid was proposed, and the citric acid was selected on the basis of its superior properties containing low damage to the structure of Ti-LIS (titanium loss ≤0.05%) and high lithium ions concentration enrichment (4.06 g L−1) with 0.2 mol L−1 in elution solutions. Meanwhile, the adsorption performance of Ti-LIS treated with citric acid was also investigated by batch experiments, and the results revealed the adsorptive ability of the Ti-LIS could reach up to 52 mg g−1 in LiOH solutions (1.8 g L−1 Li, pH 12). Furthermore, the competitive absorbing and recycling results demonstrated that the Ti-LIS treated with citric acid still has a remarkable selectivity to Li+ and stable adsorptive function. Consequently, it elucidated that the citric acid was an effective eluting medium in the application of LIS.

Hybrid Cation Exchange Membranes with Lithium Ion‐Sieves for Highly Enhanced Li+ Permeation and Permselectivity

AbstractCation exchange membranes (CEMs) hold promise for efficient and environment‐friendly lithium extraction from salt‐lake brine. However, development and practical application of CEMs are significantly hindered by the low Li+ permeation and permselectivity. Herein, novel hybrid CEMs are developed by dispersing lithium ion‐sieves (LMO) into sulfonated poly(ether ether ketone) matrix. Two kinds of LMOs are synthesized including acidified LMO (HMO) and its sulfonation compound (HMO‐S). The physicochemical property and separation performance of hybrid membranes are systematically investigated. The uniformly dispersed HMO and HMO‐S enhance the thermal, mechanical stability, and swelling resistance of hybrid membranes. Furthermore, these fillers obviously reduce the area resistance from 8.0 to less than 6.0 Ω cm−2. Importantly, the unique Li+ transfer channels in HMO/HMO‐S efficiently elevate the Li+ permeation by up to 66%. While the “ion‐sieve effect” of the channels weakens the migration of Mg2+ and K+, thus notably rising Li+/Mg2+ and Li+/K+ permselectivities by ≈5 times, which is difficult to realize with conventional fillers. Comparing with HMO, HMO‐S shows higher improvement for permselectivity because of the reduced area resistance of the resultant hybrid membrane. This study paves a way to design and development of selective Li+ exchange membranes for transport and separation applications.

Facile Synthesis of Magnetically Recyclable Fe-doped Lithium Ion Sieve and Its Li Adsorption Performance

In this paper, magnetically recyclable Fe-doped lithium ion sieves (LFMO) with enhanced structure stability were synthesized using a solid state reaction method. The structure, adsorption capacity,...

Recovery of manganese from sulfuric acid leaching liquor of spent lithium-ion batteries and synthesis of lithium ion-sieve

A novel process of recovery of Mn as lithium ion-sieve from H2SO4 leaching liquor of spent lithium-ion batteries was developed. After precipitation of Fe3+ and Cu2+ in the leaching liquor, Mn was recovered with D2EHPA extraction followed by two-step stripping with H2SO4 solution. Lithium ion-sieve was synthesized by oxidation of the stripping solution using KMnO4, then roasting at atmosphere followed by acid leaching. The effects of solvent extraction parameters on Mn recovery rate and Co doping content on the performance of lithium ion-sieve were investigated. The result indicates that through secondary countercurrent solvent extraction, Mn is fully separated from Ni and a MnSO4 solution containing a small amount of Co is obtained. Co can incorporate into the lattice of lithium ion-sieve and improve the structure stability and adsorption capacity. The Co doped lithium ion-sieve shows Li adsorption capacity of 33.1 mg g−1 and Mn dissolution rate of 1.39%. The total recovery efficiency of Mn is 84.6%. The process provides a simple method for recovery and utilization of Mn in the spent lithium-ion batteries.

A new high-efficiency process for Li+ recovery from solutions based on LiMn2O4/λ-MnO2 materials

The manganese loss of lithium ion-sieves was high in the acid desorption process. Thus, electrically switched ion exchange (ESIX) has been investigated attempting to recover Li+ from brine in recent years. A new high-efficiency process for Li+ recovery from solutions was successfully applied in this study based on LiMn2O4/λ-MnO2 structures. The adsorption and desorption happened simultaneously at positive and negative electrodes, respectively. The adsorption rates increased with the increasing operating voltages. The adsorption capacity was 3.5 mmol·g−1 under the optimal voltage (0.75 V). Besides, the adsorption rates and adsorption capacities were mainly affected by operating temperatures, initial Li+ concentrations in adsorption solutions, and initial Li+ concentrations in desorption solutions, respectively. All the experiments results showed lower manganese losses (less than 0.05%) in desorption than traditional methods (1.2%–2.5%). The XRD results denoted that the λ-MnO2 electrode converted into the LiMn2O4 electrode after adsorption. On the contrary, the LiMn2O4 electrode converted back into the λ-MnO2 electrode after desorption. Cyclic experiments indicated that the electrodes in the adsorption-desorption process exhibited excellent regenerability.

Preparation and characterization of porous HMO/PAN composite adsorbent and its adsorption–desorption properties in brine

Lithium-ion sieve (LIS) formation technology for Li+ recovery from seawater or brine is very important. In this article, the different types of H1.6Mn1.6O4 (HMO) composite adsorbents, including granular (HMO/PAN-G), nanofiber flat-sheet membrane (HMO/PAN-NM), flat-sheet membrane (HMO/PAN-FM), and hollow-fiber membrane (HMO/PAN-HFM) adsorbents, were prepared via the phase-inversion method using hydrophilic polyacrylonitrile (PAN) and Li1.6Mn1.6O4 (LMO) as the binder and precursor, respectively. The effects of the formation methods on the morphology, structure, and Li+ adsorption performance of the different types of HMO/PAN composite adsorbents were investigated. The adsorption performance of HMO/PAN-HFM was better than HMO/PAN-G and HMO/PAN-FM owing to its high porosity (88.1%). Results indicated that HMO/PAN-HFM (HMO = 50 wt%) exhibits optimal adsorption performance, with an optimum adsorption capacity of 18.1 mg g−1, corresponding to 91.4% of the adsorption capacity of HMO powder (19.8 mg g−1). Using Li+ solutions and simulated brine, the Li+ adsorption percentages were found to be 91.8% and 87.6%, respectively, at 12 h. The Li+ selectivity of HMO/PAN-HFM was 183–453 times those of other metal ions. These results indicate that PAN is an excellent carrier of HMO, and high-porosity HMO/PAN-HFM is promising as an LIS composite adsorbent.

Adsorption of Li by a lithium ion-sieve using a buffer system and application for the recovery of Li from a spent lithium-ion battery

A lithium ion-sieve manganese oxide (MO) derived from Li-enriched MO was prepared by the glycolic acid complexation method. The Li adsorption performance in a LiCl–NH3·H2O–NH4Cl buffer solution, simulated a spent lithium-ion battery (LIB) processing solution, and actual spent LIB processing solution were studied. An adsorption capacity of 27.4 mg/g was observed in the LiCl–NH3·H2O–NH4Cl buffer solution (Li concentration of 0.2 mol/L, pH = 9), and the adsorption behavior conformed to the Langmuir adsorption isotherm equation with a linear correlation coefficient (R2) of 0.9996. An adsorption capacity of 19 mg/g was observed in the simulated buffer spent battery solution (Li concentration of 0.15 mol/L, pH = 7), and an adsorption capacity of 17.8 mg/g was observed in the actual spent battery solution (Li concentration of 0.15 mol/L, pH = 7). X-ray diffraction, scanning electron microscope, and infrared spectrum results revealed that the structure and morphology of MO are stable before and after adsorption, and the adsorption of MO in all of the abovementioned buffer systems conforms to the Li+–H+ ion-exchange reaction mechanism. The lithium ion-sieve MO demonstrates promise for the recovery of lithium from spent LIBs.

Lithium adsorption from brine by iron-doped titanium lithium ion sieves

Iron-doped lithium titanium oxides were prepared via a solid-state reaction and transformed into lithium ion sieves by acid treatment. Scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy showed that Fe3+ was doped into the Ti–O lattice and Ti–Fe–O bonds were formed. Iron-doping improved lithium ion adsorption from brines. The saturated adsorption capacity of the iron-doped ion sieves in brine (Li+ 1.56g/L, pH=8.8) was 34.8mg/g. Lithium ion adsorption fitted pseudo-second-order kinetic and Langmuir equations, indicating that lithium ion adsorption on iron-doped lithium ion sieves was chemical and predominantly monolayer. In addition, the iron-doped ion sieves showed excellent selectivity for lithium ion and good recyclability. These iron-doped ion sieves therefore provide effective lithium adsorbents for practical applications.

Lithium ion sieve synthesized via an improved solid state method and adsorption performance for West Taijinar Salt Lake brine

Monoclinic β-Li2TiO3 (LTO) is regarded as a lithium adsorbent precursor. In order to inhibit agglomeration during solid state reaction, C2H3LiO2·2H2O instead of Li2CO3 was firstly used as the lithium resource to synthesize LTO. Lithium ion sieve H2TiO3 (HTO) was then obtained by acid treatment of LTO. Physicochemical properties of obtained LTO and HTO were characterized via powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and particle size distribution analysis (PSD). Lithium adsorption selectivity and stability of prepared HTO for West Taijinar Salt Lake were investigated. Solid state reaction mechanism of C2H3LiO2·2H2O and TiO2 was investigated by TG-DTA analysis. Results show that melting of C2H3LiO2·2H2O (at 64.5 °C) during the early calcination stage could form liquid–solid phase and remarkably improve mixing of C2H3LiO2·2H2O and TiO2. Compared to Li2CO3 used as the lithium resource, huge heat and gases released during the reaction of dehydrated C2H3LiO2·2H2O and TiO2 (between 380 °C and 515 °C) accelerate the nucleation process and effectively inhibits agglomeration, which leads to a smaller particle size (∼70 nm). It is shown that lithium uptake and adsorption rate were improved because of easier mass transfer during the ion-exchange process. Lithium adsorption behavior could be well described by the Langmuir isotherm and pseudo-second-order kinetic model. Seperation factor α (Li/Mg) of obtained HTO in West Taijinar Salt Lake brine reached 5441.17, meaning remarkable lithium adsorption selectivity in real lake brine. Besides, adsorption uptake remained 24.5 mg/g after 5 cycles in West Taijinar Salt Lake brine, which indicates obtained HTO has good stability.

Yolk-shell structured composite for fast and selective lithium ion sieving

Yolk-shell structured C@Li4Ti5O12 microspheres composed of carbon core (ca. 500 nm) and sea urchin-like Li4Ti5O12 shell (ca. 400–500 nm) are formed by hydrothermally treating the core–shell structured C@TiO2 in the EtOH/H2O solution of LiOH and calcining it in N2 atmosphere. Yolk-shell structured TiO2-type lithium ion sieve is further transformed from C@Li4Ti5O12 through the acid treatment, which have a high specific surface area of 201.74 m2/g. The composite shows adsorption capacity towards Li+ proportional to the pH value in the range of 7–13. The adsorption reaches equilibrium within 2 h with a high equilibrium adsorption capacity of 28.46 mg/g under alkaline conditions, which is ca. 8 times the value of ordinary TiO2 lithium ion sieve with comparable size and surface area, demonstrating the enhanced adsorption is attributed to the generation of more accessible surficial voids by replacing internal part with light carbon core. The adsorption follows Freundlich and pseudo-second-order kinetic models with a high rate constant of 0.015 g/(mg·min). The selective adsorption to Li+ is verified in the presence of K+, Na+, Ca2+ and Mg2+.

Mesoporous hollow silicon spheres modified with manganese ion sieve: Preparation and its application for adsorption of lithium and rubidium ions

In this work, mesoporous hollow silicon spheres modified with 3‐aminopropyl‐ triethoxysilane (APTES) of loaded hydrogen manganese oxide lithium ion sieve (APTES/HMO‐ HS) was prepared. The structure and morphology of as‐prepared APTES/HMO‐HS were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray photoelectron spectroscopy, transmission electron microscopy and nitrogen adsorption‐desorption measurements. The Brunner‐Emmet‐Teller (BET) surface areas, pore diameters and pore volumes of APTES/HMO‐HS decreased gradually, while the Li:Mn:Si molar ratios range from 1:1:50 to 1:1:10. The obtained hierarchical porous APTES/50HMO‐HS has a high specific surface area (557.1694 m2 g‐1). The lithium and rubidium ions solutions were used to measure the adsorption performance of the APTES/HMO‐HS adsorbent. The pseudo‐first‐order and pseudo‐second‐order kinetics, Langmuir and Freundlich isotherms of APTES/HMO‐HS were investigated; suggesting that the adsorption kinetics can be described by the pseudo‐second‐order kinetic model and the adsorption isotherms well fits the Langmuir isotherm equation. The obtained results show that the prepared APTES/HMO‐HS exhibits excellent abilities to simultaneously and selectively recover Li+ and Rb+ (11.22 mg·g‐1 and 8.31 mg·g‐1) and have a promising application in the simultaneous adsorption of lithium and rubidium ions.

Preparation of three-dimensional macroporous–mesoporous lithium ion sieve with high Li+ adsorption capacity

A three-dimensionally macroporous–mesoporous lithium ion sieve (3DM-H4Ti5O12) was transformed from 3DM-Li4Ti5O12 through washing with HCl solution, which was synthesized by a combination of hydrothermal and low-temperature calcination (600 °C) treatment, using polystyrene microarray as hard-template, and titanium isopropoxide and lithium acetate as co-precursors. The influence of HCl concentration and temperature on the deintercalation rate of Li and Ti from Li4Ti5O12 was specifically explored to maximize the extraction ratio of Li/Ti. The acceleration of Li extraction and insertion in a porous structure was verified using nonporous Li4Ti5O12 as a control. 3DM-H4Ti5O12 showed superior Li+ adsorption performance (5.51 mmol/g) compared with its nonporous counterpart (1.12 mmol/g), which was ascribed to the reduced Li+ mass transfer resistance in the highly interconnected porous channel. The ion selectivity of the 3DM-H4Ti5O12 lithium ion sieve followed the order of Li+ > Na+ ~ Ca2+ > K+ > Mg2+. The adsorption performance could be maintained after six cycles. The high adsorption capacity, excellent selectivity, and good recyclability demonstrate the prosperous potential application of 3DM-H4Ti5O12.

Selective adsorption of lithium from high Mg-containing brines using HxTiO3 ion sieve

The prepared titanium type lithium ion sieve HxTiO3 are characterized and tested as adsorbents for selective adsorption of lithium from high Mg-containing brine. The maximum adsorption capacities of Li+, Na+, K+, Ca2+ and Mg2+ ions onto HxTiO3 reached 36.34, 1.93, 1.99, 2.58 and 3.53mg/g, respectively, under the initial pH8.8 at 25°C for 24h. Adsorption isotherms and kinetic analysis indicated that the adsorption of Li+ ions and other cations onto HxTiO3 followed Langmuir isotherm model and pseudo-second order kinetic equation. A diffusion model simulation showed that the Li+ ions had the highest external diffusion coefficients (7.7×10−2cms−1) while the other cations had small effect on the adsorption rate of Li+. The Biot number was >100 signified that these ions adsorption onto HxTiO3 were controlled by the internal diffusion. The separation factors (α) of Li+ over other cations were much >1. In particular, the α value of Li+ over Mg2+ reached 4783, indicating the high selectivity for Li+. In addition, the Li+ ion adsorption capacity kept constant during the six adsorption-desorption cycles and molar ratio of Mg to Li of eluents was as low as 0.08, indicating that the HxTiO3 ion sieve could effectively extract Li+ from the enriched brine.

Superior lithium adsorption and required magnetic separation behavior of iron-doped lithium ion-sieves

The recent research on adsorption-based lithium recovery from lithium-containing solutions has been centred on adsorption capacity and separation of lithium ion-sieves powder from solutions. Herein, an effective iron-doped lithium titanium oxide (Fe-doped Li2TiO3) was synthesized by Fe-doping via solid state reactions followed by acid treatment to form iron-doped lithium ion-sieves (Fe/Ti-x(H)). The resulting solid powder displays both superior adsorption capacity of lithium and high separation efficiency of the adsorbent from the solutions. SEM imaging and BET surface area measurement results showed that at Fe doping levels x≤0.15, Fe-doping led to grain shrinkage as compared to Li2TiO3 and at the same time the BET surface area increased. The Fe/Ti-0.15(H) exhibited saturated magnetization values of 13.76emug−1, allowing effective separation of the material from solid suspensions through the use of a magnet. Consecutive magnetic separation results suggested that the Fe/Ti-0.15(H) powders could be applied at large-scale and continuously removed from LiOH solutions with separation efficiency of 96% or better. Lithium adsorption studies indicated that the equilibrium adsorption capacity of Fe/Ti-0.15(H) in LiOH solutions (1.8gL−1 Li, pH 12) reached 53.3mgg−1 within 24h, which was higher than that of pristine Li2TiO3 (50.5mgg−1) without Fe doping. Competitive adsorption and regeneration results indicated that the Fe/Ti-0.15(H) possessed a high selectivity for Li with facile regeneration. Therefore, it could be expected that the iron-doped lithium ion-sieves have practical applicability potential for large scale lithium extraction and recovery from lithium-bearing solutions.

Recovery of lithium from the effluent obtained in the process of spent lithium-ion batteries recycling

A novel process of lithium recovery as lithium ion sieve from the effluent obtained in the process of spent lithium-ion batteries recycling is developed. Through a two-stage precipitation process using Na2CO3 and Na3PO4 as precipitants, lithium is recovered as raw Li2CO3 and pure Li3PO4, respectively. Under the best reaction condition (both the amounts of Na2CO3 and Li3PO4vs. the theoretical ones are about 1.1), the corresponding recovery rates of lithium (calculated based on the concentration of the previous stage) are 74.72% and 92.21%, respectively. The raw Li2CO3 containing the impurity of Na2CO3 is used to prepare LiMn2O4 as lithium ion sieve, and the tolerant level of sodium on its property is studied through batch tests of adsorption capacity and corrosion resistance. When the weight percentage of Na2CO3 in raw Li2CO3 is controlled less than 10%, the Mn corrosion percentage of LiMn2O4 decreases to 21.07%, and the adsorption capacity can still keep at 40.08 mg g−1. The results reveal that the conventional separation sodium from lithium may be avoided through the application of the raw Li2CO3 in the field of lithium ion sieve.

Lithium ion-sieve: Characterization and Li+ adsorption in ammonia buffer system

In this account, manganese oxide lithium ion-sieve MO derived from spinel lithium-enriched manganese oxide Li1.45Mn1.67O4 (LMO) was prepared and its structure, morphology and valence of Mn for both LMO and MO were analyzed by XRD, SEM and XPS, respectively. The results revealed that after acid leaching, MO maintained the spinel structure and porous morphology of LMO, which was beneficial to the Li+ adsorption process. The estimated average valence of Mn in MO was 3.91. The adsorption of lithium for MO in a LiCl-NH3·H2O-NH4Cl buffer solution at pH=9 showed the best fit with a Langmuir isotherm, indicating that a Li+-H+ ion exchange mechanism took place. The adsorption kinetics study demonstrated that the Li+ adsorption process of MO complied with a pseudo-second order model, where the control step of the adsorption process changed with temperatures. The ion exchange isotherms showed that the ion-sieve MO could complete an exchange reaction in LiCl-NH3·H2O-NH4Cl buffer solution. Finally, the MO was applied to recover lithium from a simulated ammoniacal spent lithium ion battery processing solution with a capacity of 15mg/g.

Continuous lithium mining from aqueous resources by an adsorbent filter with a 3D polymeric nanofiber network infused with ion sieves

Electrospun composite nanofiber (NF) was fabricated and employed as an adsorbent membrane filter in a continuous Li+ mining process from seawater. The filter was composed of a hydrophilic polyacrylonitrile (PAN) matrix infused with lithium ion sieves (LIS) H1.6Mn1.6O4. Characterization of the LIS/PAN NF confirmed its favorable structural and surface properties for effective Li+ adsorption. The LIS/PAN NF was mechanically suitable as a microfiltration membrane with high water flux and low pressure requirement. Breakthrough experiments at varied feed concentrations (Cf), seawater flowrates (F), and NF thicknesses (Z) revealed the dynamic adsorption behavior of the filter. The seawater residence time was most critical and must be kept ⩾0.12min at any given Cf and Z to maximize the Li+ capacity of the filter. This can be conveniently achieved by adjusting the F of the process. Analogous to a packed bed system, the predictive power of nine breakthrough models were determined through non-linear regression analyses. Results reveal that bed-depth-space-time, Bohart-Adams (BA) and Thomas models adequately predicted the performance of the filter albeit BA exhibited the best agreement. Meanwhile, Wolborska failed to converge with any of the experimental results while Yoon-Nelson, Wang, Clark, dose-response, and modified dose-response were too simple to provide any meaningful information. Cycled Li+ adsorption-desorption runs successfully collected and concentrated Li+ in a mild acid stripping solution. After ten cycles, Li+ was separated 155–1552 times more efficiently than Na+, K+, Mg2+ and Ca2+. Overall results demonstrate the potential of LIS/PAN NF as an adsorbent membrane filter for continuous Li+ mining from aqueous resources.

H2TiO3 Composite Nanofibers for Lithium Recovery from Spent Lithium-Ion Secondary Batteries

Lithium recovery attempts from spent lithium-ion batteries (LIBs) often employed complex methods utilizing toxic chemicals. In this study, a relatively facile and environmentally benign lithium recovery process was developed using H2TiO3 (HTO) as a highly selective lithium-ion adsorbent. This lithium ion sieve (LIS) has a chemically stable structure and remarkably higher theoretical Li+ capacity (126.47 mg/g) than manganese-based LIS. The low titanium dissolution of HTO upon acid pickling makes it an ideal LIS for lithium recovery. However, in its powder form, HTO application in actual systems is limited due to difficulty in its handling. The HTO particles must be incorporated in a suitable support for its feasible utilization. Herein, electrospun nanofibers with unique dimensional properties were utilized to serve as three-dimensional frameworks for HTO. Different types of polymeric (PAN, PSf, PVC, and PVDF) nanofibers with varied HTO loading were prepared by electrospinning method. The composite nanofibers were characterized by SEM, UTM mechanical test and applied for lithium adsorption. It was determined that PAN composite nanofibers with 100 wt.% HTO loading showed the highest adsorption capacity (31.4 mg g-1) and superior mechanical property. It retained up to 93.6% of the adsorption capacity of the pure H2TiO3 powder (33.6 mg g-1). The PAN-HTO nanofiber was then employed to recover Li+ from spent LIBs. The spent batteries were dismantled and sonicated in deionized water to elute Li+ from the waste. The resulting solution was then filtered through the PAN-HTO nanofiber membrane to capture the Li+. The captured Li+ were easily retrieved by mild acid treatment of the spent PAN-HTO nanofiber, which was also regenerated for reuse. Overall, the results of the study showed the feasibility of using PAN-HTO nanofiber for continuous and efficient recovery of lithium ions from spent LIBs. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2009-0093816) and Ministry of Science, ICT and future Planning (2015R1A2A1A15055407).

Electrochemical Lithium Recovery from Aqueous Sources

Lithium shortage is inevitable, given the massive growth in its demand for use in transportation industry and various technologies. Consequently, recovery of lithium from seawater and brine is gaining attention to potentially alleviate the impending crisis. Two widely investigated methods for lithium recovery from seawater and brine deposits are adsorption using inorganic lithium ion sieves (LIS) and electrochemical processes. But the former has a drawback due to the use of toxic solvents which negatively affects the environment. Herein, an efficient type of lithium recovery approach is proposed by systematically designing an electrochemical system to sequester Li+ from aqueous sources. An electrochemical cell was designed to selectively intercalate Li+ into the anode during charging phase. A microcell reactor was prepared and investigated for its feasibility to capture lithium ions (Li+). The reactor consists of a three-electrode assembly with an Li+-selective intercalating electrode, a chloride-capturing silver electrode, and Ag/AgCl reference electrode. Repetitive cyclic voltammetry and galvanostatic cycling showed highly selective and stable electrode system for aqueous Li+ uptake and release. The energy efficiency of the process was also investigated and compared with other electrochemical Li+ recovery methods. Overall, the results demonstrate the ability of the electrochemical system to selectively recover Li+ from aqueous sources. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2009-0093816) and Ministry of Science, ICT and future Planning (2015R1A2A1A15055407).