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Lithium fluoride

Lithium fluoride (LiF) is an composed of cations and anions, forming a white, odorless crystalline solid that occurs as a dry powder or cubic crystals. It is the least soluble among the fluorides, with a of approximately 0.134 g/100 g at 25 °C, and exhibits high stability with a of 848 °C and a of 1673 °C. Lithium fluoride has a molecular weight of 25.94 g/mol, a of 2.64 g/cm³, and low hygroscopicity compared to other halides. As a highly ionic substance, it possesses a high constant of about 9.0 and excellent transparency across (UV), visible, and (IR) spectra, extending into the UV region down to 121 . However, it is a strong irritant to and eyes and toxic if ingested, classified as acutely toxic with hazard codes H301, H315, H319, and H335. Due to its unique properties, lithium fluoride is used in ceramics and manufacturing as a , in optical components like UV windows and IR lenses, in thermoluminescent dosimeters for detection, in mixtures for nuclear reactors, and as a precursor for electrolytes. Emerging applications include and rechargeable batteries.

Properties

Physical properties

Lithium fluoride (LiF) is an with the molecular formula LiF and a of 25.939 g/mol. It typically appears as a colorless or white crystalline solid, often in the form of cubic crystals or fine powder. Key physical properties of lithium fluoride are summarized in the following table:
PropertyValueConditions/Notes
2.640 g/cm³At 20 °C
848 °C (1,121 K)-
1,676 °C (1,949 K)-
Refractive index (n_D)1.392At 0.6 μm wavelength
These values establish lithium fluoride's stability at high temperatures and its utility in optical applications due to its transparency and low variation. Lithium fluoride exhibits limited in , approximately 0.27 g/100 mL at 18–20 °C, with solubility increasing significantly in hot (up to about 1.3 g/100 mL at higher temperatures near 90 °C); it is insoluble in common organic solvents such as and acetone. The material also demonstrates good thermal properties, including a thermal conductivity of about 13.9 W/(m·K) at and a of 41.6 J/mol·K at 298 K, which contribute to its effectiveness as a medium in specialized applications.

Chemical properties

Lithium fluoride (LiF) is an ionic compound composed of lithium cations (Li⁺) and fluoride anions (F⁻), bonded through strong electrostatic interactions typical of alkali metal halides. It crystallizes in the rock salt (NaCl-type) structure, featuring a face-centered cubic lattice where each Li⁺ ion is octahedrally coordinated by six F⁻ ions, and vice versa. The crystal structure belongs to the space group Fm3m, with a lattice parameter a = 4.026 Å at room temperature. This arrangement contributes to its high stability, as LiF does not decompose under standard conditions but slowly hydrolyzes in moist air according to the reaction LiF + H₂O → LiOH + HF, forming surface layers of lithium hydroxide and releasing trace hydrogen fluoride. LiF exhibits limited reactivity, being insoluble in most organic solvents and water, but it dissolves in strong acids like HCl, generating HF gas: LiF + HCl → LiCl + HF. As a fluorinating agent, it participates in exchange reactions, such as 3 LiF + AlCl₃ → AlF₃ + 3 LiCl, facilitating the preparation of other metal fluorides. Aqueous solutions of LiF are neutral to slightly basic (pH ≈ 8–9 for moderate concentrations) owing to the hydrolysis of F⁻ ions, which behave as a weak base: F⁻ + H₂O ⇌ HF + OH⁻, with the equilibrium shifted due to the weakness of HF (pK_a = 3.17). Electrochemical properties of LiF are dominated by the Li⁺ ion, with the standard reduction potential for Li⁺ + e⁻ → Li being -3.04 V versus the , underscoring lithium's high reactivity as a in electrochemical systems.

Production

Laboratory preparation

Lithium fluoride can be prepared in the laboratory by reacting with , a that produces through a straightforward acid-base accompanied by gas evolution. The balanced for this process is: \mathrm{Li_2CO_3 + 2HF \rightarrow 2LiF + CO_2 + H_2O} In practice, solid lithium carbonate is added to an aqueous solution of hydrofluoric acid, often in excess, with the mixture stirred under controlled conditions to ensure complete reaction; the carbon dioxide gas is vented, and the resulting lithium fluoride precipitates or is obtained by evaporation to dryness followed by gentle heating to remove residual acid. An alternative laboratory method involves the reaction of lithium hydroxide with hydrofluoric acid, which yields lithium fluoride directly without gas byproduct. The equation is: \mathrm{LiOH + HF \rightarrow LiF + H_2O} Here, aqueous solutions of lithium hydroxide and hydrofluoric acid are mixed, leading to the formation of lithium fluoride, which can be isolated by filtration or evaporation. This approach is simpler for small-scale synthesis due to its lack of gaseous emissions. Following synthesis by either method, lithium fluoride is typically purified by recrystallization to achieve high purity suitable for research applications. The crude product is dissolved in hot water—exploiting its low solubility (about 0.13 g/100 mL at 20°C, increasing with temperature)—and allowed to cool slowly, promoting the formation of purer crystals; alternatively, ethanol can be used as a solvent for recrystallization in cases where water introduces impurities. The purified crystals are then filtered, washed, and dried under vacuum or mild heat. Due to the extreme toxicity and corrosivity of , which can cause severe burns, tissue necrosis, and systemic even at low concentrations, stringent handling precautions are essential during preparation. All must be conducted in a well-ventilated chemical , with personnel wearing chemical-resistant gloves (e.g., or Viton over ), full-face shields, lab coats, and aprons; gel should be readily available as an for skin exposure, and immediate medical attention is required for any contact. should always be added to (never the reverse) to prevent violent , and waste must be neutralized before disposal. In laboratory settings, these methods generally provide high yields, often exceeding 95% based on input, with purities routinely achieving >99% after recrystallization, as verified by techniques such as ICP-MS for trace impurities; further refinement can reach 99.9% for specialized uses, though minor losses occur during purification steps.

Industrial manufacturing

The primary industrial route for lithium fluoride (LiF) production involves the neutralization of (LiOH) or (Li₂CO₃) with (HF) in specialized reactors designed to handle corrosive fluorides. This process typically occurs in aqueous or semi-aqueous conditions, where the lithium salt is dissolved and reacted with HF to precipitate LiF, accompanied by by-products such as water or (from the carbonate route). Lithium sources are primarily derived from extraction or hard-rock , ensuring a steady supply for large-scale operations. An alternative method utilizes lithium chloride (LiCl), often sourced from concentrated brines, reacted with hydrofluoric acid or fluorosilicic acid (H₂SiF₆) as a cost-effective fluoride source. This reaction proceeds in stirred reactors at controlled temperatures (around 50–80°C) to form LiF precipitate while generating by-products like hydrochloric acid or silica compounds, which require neutralization and recovery to minimize environmental impact. By-product management, particularly CO₂ from carbonate-based reactions, involves capture systems such as scrubbers to comply with emission regulations, with energy demands primarily from heating and agitation estimated at 5–10 MJ/kg of LiF produced. Following , the crude LiF undergoes purification through to remove unreacted salts, followed by in ovens and at temperatures up to 800°C to achieve purities exceeding 99.9%, essential for applications like battery electrolytes. Global production capacity reached approximately 83,000 metric tons in 2024, with the market volume projected to grow at a CAGR of 5.18% through 2035; major producers including American Elements in the U.S. and Chinese firms like Corp., contributing to an annual output in the tens of thousands of tons amid rising . Cost factors are heavily influenced by lithium prices, with LiF trading at around $15–18 per kg in 2025, reflecting fluctuations in brine-derived lithium availability.

Applications

Battery technology

Lithium fluoride serves as a key precursor in the synthesis of (LiPF₆), the predominant salt in lithium-ion batteries. The production of LiPF₆ typically involves a multi-step where lithium fluoride reacts with phosphorus pentafluoride (PF₅), often generated in situ from , chlorine gas, and ; a simplified representation is LiF + PF₅ ⇌ LiPF₆, conducted in solvents such as anhydrous , liquid , or under controlled conditions like temperatures from -30°C to 60°C and pressures of 1-10 bar. This reaction enables the formation of high-purity LiPF₆ through subsequent or steps, ensuring suitability for battery applications. In lithium-ion batteries, LiPF₆ dissociates into Li⁺ and PF₆⁻ ions in organic carbonate solvents, providing high ionic conductivity essential for efficient charge-discharge cycles. The inherent thermal stability of lithium fluoride contributes to reducing , as LiF's high (around 845°C) and chemical inertness help form protective layers that mitigate breakdown under operational stresses. This stability enhances overall battery safety and longevity by limiting volatile byproduct formation during elevated temperatures. In solid-state batteries, lithium fluoride plays a critical role as a component of the solid interphase (SEI), particularly on metal anodes, where it forms a robust, ion-permeable layer that suppresses growth and maintains structural integrity during volume changes. Solvent-derived LiF-rich SEIs, combined with components, improve Coulombic and cycling performance by protecting against degradation. The growing adoption of lithium-ion and solid-state batteries in electric vehicles has driven lithium fluoride demand, with battery-grade material projected to exhibit an approximate 15% annual growth rate from 2025 onward, fueled by its role in enhancing performance and safety. A primary challenge in these applications stems from the moisture sensitivity of LiPF₆ derived from lithium fluoride, which decomposes upon water exposure via LiPF₆ → LiF + PF₅, followed by PF₅ + H₂O → POF₃ + 2, generating corrosive () that can etch electrodes, degrade separators, and increase . This necessitates rigorous moisture control during manufacturing to prevent performance issues and safety risks.

Molten salt applications

Lithium fluoride is a key component in the FLiNaK eutectic , composed of LiF-NaF-KF in a 46.5-11.5-42 % ratio, which serves as a high-temperature for advanced energy applications. This formulation significantly depresses the to 454°C, compared to 848°C for pure LiF, enabling operation at lower temperatures while maintaining fluidity for . The exhibits favorable thermal properties, including a of approximately 1.9 J/g·K and stability up to over 900°C, with low that supports efficient and transfer without excessive . In reactors and (CSP) plants, FLiNaK acts as a and , leveraging its high thermal and capacity to store and transport heat effectively in high-temperature environments. For CSP systems, it facilitates by absorbing solar heat during the day and releasing it for power generation at night, potentially operating in cycles up to 700°C or higher. Additionally, lithium fluoride is employed as a flux additive in the Hall-Héroult process for aluminum production, where it modifies the molten electrolyte to enhance electrical , reduce the bath's liquidus , and improve current efficiency, typically at concentrations around 1-2 wt%. Despite these advantages, FLiNaK poses corrosion challenges to container materials, particularly nickel-based like Hastelloy N, due to selective of elements such as and at grain boundaries. Under stress at 700°C, rates can increase up to fourfold, leading to intergranular cracking and of about 5 mg/cm² over 240 hours, exacerbated by impurities like ions that promote galvanic effects and precipitation. Mitigation strategies often involve modifications or salt purification to minimize these issues in practical deployments.

Optical uses

Lithium fluoride (LiF) is valued in optical applications for its broad transmission spectrum, spanning from the vacuum ultraviolet (VUV) to the mid-infrared (IR), specifically 120 nm to 6 μm, enabling its use in components that require high transparency across UV, visible, and IR wavelengths. This wide range arises from its large bandgap and low dispersion, making it suitable for environments where minimal light loss is critical. Additionally, high-quality LiF exhibits a low absorption coefficient, below 0.01 cm⁻¹ at 193 nm, which supports efficient light propagation in deep UV systems without significant attenuation. In semiconductor manufacturing, LiF serves as a lens material in VUV lithography systems operating at 193 nm, such as those using ArF lasers, due to its compatibility with setups requiring high-index s for precise patterning. For analytical instrumentation, LiF prisms and windows are employed in IR spectrophotometers, facilitating the examination of samples including those for content determination, as the material's transmission up to 6 μm covers key bands without from the optic itself. Optical-grade LiF single crystals are typically prepared using the , which involves pulling a from a molten LiF bath under controlled conditions to minimize impurities and defects, ensuring homogeneity and clarity essential for precision . Historically, LiF played a pioneering role in early fluoride-based , with its prisms introduced in the 1940s for IR spectroscopy instruments, extending spectral coverage to 5.9 μm and advancing the development of fluoride precursors for broader optical systems.

Radiation detection

Lithium fluoride, particularly when doped with magnesium and titanium (LiF:Mg,Ti), is extensively used in thermoluminescent dosimetry (TLD) under the commercial designation TLD-100 for radiation detection and monitoring. This doping enhances its thermoluminescent properties, enabling the material to store energy from ionizing radiation and release it as light upon subsequent heating. The mechanism in TLD-100 involves the trapping of charge carriers created by gamma or radiation exposure; heating the material to around °C releases these carriers, producing emission bands primarily at approximately nm (corresponding to a of about 3.0 ) and a secondary band near 500 nm (2.5 ). This blue-violet emission is detected by tubes in TLD readers, with the integrated light output proportional to the . TLD-100 exhibits a linear dose response from about 10 μGy to 10 for photons and electrons, making it suitable for personal dosimeters in environments with varying levels. Its effective of 8.2 closely matches that of (approximately 7.4), providing tissue-equivalent response for accurate in mixed fields without significant energy dependence. The dosimeters are prepared by doping high-purity LiF powder with trace amounts of magnesium (around 160 ppm) and (about 4 ppm), followed by the mixture under controlled conditions to form compact chips, typically 3.2 × 3.2 × 0.9 mm in size. These chips are annealed before use (e.g., 1 hour at 400°C followed by 24 hours at 80°C) to reset traps and ensure reproducibility. In applications, TLD-100 chips are employed in personal monitoring badges for nuclear workers to track cumulative exposure and in medical radiology for verifying dose delivery in radiotherapy and diagnostic procedures, offering high sensitivity down to milliroentgen levels and reusability after readout.

Nuclear applications

Lithium fluoride (LiF) plays a critical role in nuclear applications, particularly in molten salt reactors (MSRs), where it serves as a primary component in fluoride salt mixtures used as both coolants and fuel solvents. In these systems, LiF is combined with other fluorides, such as beryllium fluoride (BeF₂) and thorium fluoride (ThF₄), to form stable, high-temperature liquids that dissolve fissile materials like uranium tetrafluoride (UF₄). For instance, the proposed fuel salt composition for thorium breeder reactors includes approximately 72 mol% LiF, 16 mol% BeF₂, 12 mol% ThF₄, and trace UF₄, enabling efficient heat transfer and fuel dissolution at operating temperatures around 600–700°C. A key property of stems from its isotopes, especially the ⁶Li variant, which exhibits high neutron absorption cross-section for thermal neutrons. The reaction ^6\mathrm{Li} + n \rightarrow ^4\mathrm{He} + ^3\mathrm{H} releases approximately 4.8 MeV of energy and produces (³H), making enriched LiF valuable for generation in fusion fuel cycles or as a neutron multiplier in certain designs. Natural in LiF contains about 7.5% ⁶Li, with the remainder being ⁷Li, but for optimized performance, the salt is often isotopically enriched—either to increase ⁶Li content for enhanced neutron capture and yield or to deplete ⁶Li (enriching ⁷Li to >99%) to minimize unwanted production and in applications. In the , LiF-based molten salts facilitate the dissolution and reprocessing of fuels, allowing for pyrochemical separation of actinides without aqueous solvents. Uranium oxide or metal can be dissolved directly into LiF mixtures at elevated temperatures, enabling electrochemical extraction of and other elements for , which supports closed fuel cycles in advanced reactors by reducing waste volume and recovering . This approach was explored in early fluoride volatility processes and remains relevant for thorium- cycles in MSRs. Historically, LiF's nuclear applications were demonstrated in the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory, operational from 1965 to 1969. The MSRE utilized a carrier salt of 65 mol% LiF, 29 mol% BeF₂, and 5 mol% ZrF₄, with 0.9 mol% UF₄ as fuel, achieving over 13,000 hours of critical operation and validating the stability of LiF salts under neutron irradiation and high temperatures up to 650°C. This experiment provided foundational data on corrosion resistance, fission product behavior, and salt chemistry, influencing subsequent MSR concepts. As of 2025, LiF remains integral to developments, particularly in fluoride-salt-cooled high-temperature reactors and MSRs aimed at sustainable fuel use and waste minimization. Companies like Kairos Power are advancing FLiBe (LiF-BeF₂) systems for demonstration units, with construction of the Hermes low-power MSR underway in using ⁷Li-enriched salts to support commercial deployment by the early 2030s, aligning with international efforts under the Generation IV International Forum.

Organic electronics

Lithium fluoride (LiF) serves as an effective cathode interlayer in organic light-emitting diodes (OLEDs) and polymer light-emitting diodes (PLEDs), typically deposited as an ultrathin layer (0.5–2 nm) between the electron transport layer and aluminum (Al) cathode to enhance electron injection. This configuration addresses the mismatch between the high work function of Al (~4.3 eV) and the lowest unoccupied molecular orbital (LUMO) levels of organic semiconductors, which often results in poor electron injection efficiency. By inserting the LiF layer, the effective work function at the cathode interface is reduced to approximately 3.0 eV, facilitating better energy level alignment and lowering the electron injection barrier. The mechanism involves the formation of an at the LiF/ interface or partial dissociation of LiF during deposition, which n-dopes the adjacent layer and promotes electron tunneling through the thin insulating LiF film. This improvement was first demonstrated in 1997 by Hung et al., who reported that a 1–2 nm LiF layer on Al cathodes in tris()aluminum (Alq₃)-based OLEDs reduced the operating voltage by more than half (from 8.5 V to 4.5 V at 100 cd/m²) and increased the external from 0.3% to 1.5%. LiF is commonly deposited via thermal evaporation in a environment, ensuring uniform, pinhole-free layers critical for device reliability. In PLEDs, the LiF/Al cathode similarly boosts device performance, with efficiency enhancements of 20–50% in and current efficiency compared to bare Al cathodes, attributed to optimized built-in potential and reduced injection barriers at optimal LiF thicknesses around 1–7 nm. These gains arise from improved charge balance, minimizing non-radiative recombination and elevating overall output. Today, LiF interlayers remain integral to commercial flexible displays in , such as foldable smartphones and wearable devices, where they contribute to higher power efficiency and operational stability on substrates. LiF is also employed in emerging perovskite light-emitting diodes (PeLEDs) as an ultrathin interlayer to improve electron injection, reduce interfacial barriers, and enhance device efficiency and stability. Similar to its role in OLEDs, LiF facilitates better charge balance and mitigates non-radiative recombination in PeLEDs, enabling high external quantum efficiencies and supporting applications in next-generation displays.

Occurrence

Natural minerals

Lithium fluoride occurs naturally in extremely rare minerals, primarily as the distinct species griceite (LiF). Griceite, the only known mineral composed essentially of lithium fluoride, forms colorless to white cubic crystals or compact, powdery botryoidal masses, often as inclusions within sodalite xenoliths or lining cavities in lithium-bearing assemblages. It exhibits an isometric crystal system with space group Fm\overline{3}m, analogous to the halite structure, and has a Mohs hardness of 4½. The type locality for griceite is the Poudrette quarry, , , , where it represents the first documented natural occurrence of lithium fluoride as a discrete phase. Additional occurrences include the Lovozero Tundry massif in the , , associated with alkaline pegmatites, and volcanic sites such as Barranco Hondo and on , , . Griceite commonly associates with villiaumite (NaF), a sodium analog in the group, in fluorine- and lithium-enriched environments like syenites and alkaline intrusions. Villiaumite itself, while primarily NaF, contributes to lithium fluoride mineralization through paragenesis, though pure LiF inclusions display the characteristic cubic habit. No other distinct lithium fluoride minerals, such as hydrated or complex variants, have been verified in natural settings. Due to the scarcity and inaccessibility of these deposits, lithium fluoride is not extracted commercially from natural minerals; lithium for industrial LiF production is instead sourced from concentrated brines or hard-rock deposits like .

Environmental presence

Lithium fluoride (LiF) exhibits low in , approximately 0.134 g per 100 mL at 25°C, which allows it to partially dissociate into Li⁺ and F⁻ ions under natural conditions. This limited solubility contributes to trace levels of these ions in , where lithium concentrations typically range from 0.006 to 0.008 mg/L (median values in U.S. public supply wells), though higher levels of 0.1–1 mg/L occur in regions with elevated geogenic sources. ions from LiF and other sources average around 0.5 mg/L in many groundwaters globally. The primary natural sources of these ions include the weathering of lithium-bearing rocks such as (LiAlSi₂O₆), which releases Li⁺ through , combined with from associated fluorine-rich minerals like or during geochemical processes. The of LiF in the is generally low due to its sparing , limiting the formation and persistence of the undissociated compound; however, the released F⁻ ions contribute to the total content in sources, where they can be taken up by organisms. Globally, trace Li⁺ and F⁻ from LiF-related dissolution show variable distribution, with notably higher concentrations in geothermal waters—for instance, lithium levels in thermal features reach up to 6.8 mg/L, with means of 3–5 mg/L across basins like and Norris Geyser Basin. These elevated levels arise from magmatic interactions and , contrasting with lower background values in non-thermal groundwaters. Ecological impacts of environmental LiF are minimal at trace concentrations, as the compound does not significantly bioaccumulate in aquatic or terrestrial organisms, and lithium ions exhibit limited trophic transfer in most ecosystems. Monitoring of fluoride from such sources focuses on standards, with the U.S. Environmental Protection Agency setting a maximum contaminant level of 4 mg/L to prevent health risks like fluorosis. No specific regulatory limits exist for in , though screening levels around 10 μg/L guide assessments of geogenic exposure.

History

Discovery and synthesis

Lithium fluoride saw initial applications as a flux in metallurgical processes during the , aiding in the reduction of melting points and impurity removal in metal production.

Commercial development

Following , lithium fluoride (LiF) saw significant commercial development through U.S. Atomic Energy Commission (AEC) projects focused on nuclear applications. In the , LiF was investigated for compositions in experimental reactors. By the , LiF's adoption expanded in both nuclear and radiation detection technologies. It served as the primary salt in the (MSRE), an 8-MWt facility that achieved criticality in 1965 and operated until 1969, validating LiF-based fluoride salts for advanced reactor coolants and fuels. Concurrently, LiF's thermoluminescent properties led to its commercialization as a tissue-equivalent dosimeter material in thermoluminescent dosimeters (TLDs), with widespread industrial availability by the mid-1960s for personnel and environmental radiation monitoring. The marked a surge in LiF's use within the burgeoning sector. With Sony's commercialization of the first rechargeable Li-ion battery in 1991, LiF emerged as a critical component in the solid electrolyte interphase (SEI) layer formed via decomposition of the , enhancing stability and performance in early commercial cells. From the to 2025, LiF experienced robust growth in optical and electronics applications. In () lithography, LiF coatings improved performance and resolution for sub-7nm nodes, with integration into ASML's EUV tools by equipment partners like and , driving adoption in high-volume since around 2015. In organic light-emitting diodes (), a 2005 patent by advanced LiF's role as an electron-injection layer in cathodes, boosting device efficiency and enabling broader commercial deployment in displays. As of 2025, global LiF production is estimated at approximately 83,000 metric tons annually, supporting a valued at around USD 700 million, fueled by in batteries, , and sectors.

Safety and handling

Health hazards

Lithium fluoride exhibits moderate upon ingestion, with an oral LD50 of 608 mg/kg in male rats according to Test Guideline 401. Symptoms of acute exposure primarily stem from the fluoride and may include , , , and , resembling those of fluoride poisoning. Chronic exposure to lithium fluoride can lead to due to accumulation of the , potentially resulting in over prolonged periods. Additionally, excessive fluoride intake exceeding 1.5 mg/L in is associated with , characterized by mottling or discoloration of in children. Inhalation of lithium fluoride irritates the , causing symptoms such as coughing, discomfort, and potential pulmonary . Primary irritation arises from the , with possible minor release of upon contact with acids. Under the Globally Harmonized System (GHS), lithium fluoride is classified as Category 4 for oral exposure and Irritation Category 2, indicating potential for harmful effects if swallowed and mild skin redness upon contact. Occupational exposure limits for lithium fluoride are established based on fluoride content: the OSHA (PEL) is 2.5 mg/m³ as fluorine (8-hour time-weighted average), while the ACGIH (TLV) is also 2.5 mg/m³ as fluorine (TWA).

Regulatory aspects

Lithium fluoride is registered under the European Union's REACH regulation (EC No. 1907/2006) due to its toxic properties, including if swallowed (H301) and potential for skin, eye, and respiratory irritation. As a classified hazardous substance, it requires the provision of safety data sheets (SDS) detailing handling, storage, and emergency measures to ensure safe use throughout the . In the United States, lithium fluoride is listed on the Toxic Substances Control Act (TSCA) Inventory, subjecting manufacturers and importers to certification requirements for compliance with TSCA import/export rules. Under the TSCA (CDR) rule (40 CFR Part 711), entities must report production or import volumes exceeding 25,000 pounds per year at a single site during the principal reporting year, providing data on , , and use to the Agency every four years. Safe handling of lithium fluoride mandates the use of (PPE), including chemical-resistant gloves, safety goggles, and protective clothing to prevent skin and eye contact, as well as respiratory protection in dusty environments to avoid inhalation. It should be stored in tightly sealed, dry containers in a cool, well-ventilated area away from moisture, acids, and incompatible materials like strong oxidizers, as it can react with water to release . Environmental precautions include avoiding release to waterways to prevent contamination. For disposal, lithium fluoride waste is typically managed as a under regulations like RCRA in the U.S., requiring neutralization with () to form insoluble before landfilling or to mitigate risks. Pure lithium fluoride is not a listed RCRA . It may be managed as characteristic if it exhibits , ignitability, corrosivity, or reactivity, though is not directly regulated under TCLP toxicity criteria; wastes with concentrations below 20% are often classified as non-hazardous for Subtitle D landfills after treatment. Transportation of lithium fluoride is regulated as a toxic substance under 3288 (Toxic solid, inorganic, n.o.s. (lithium fluoride)), classified in Class 6.1 (inhalation hazard, Packing Group III), requiring proper labeling, packaging, and documentation for road, rail, sea, and air shipment per , IMDG, and IATA standards. The Battery (EU) 2023/1542 mandates a minimum 65% recycling efficiency for recovery from lithium-ion batteries by 2025, applying to batteries that may involve lithium fluoride in electrolytes or products, requiring producers to ensure collection, treatment, and material recovery to promote principles and restrict environmental release of fluorides.

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