JP5122809B2 - Method for producing lithium fluoride - Google Patents
Method for producing lithium fluoride Download PDFInfo
- Publication number
- JP5122809B2 JP5122809B2 JP2006349822A JP2006349822A JP5122809B2 JP 5122809 B2 JP5122809 B2 JP 5122809B2 JP 2006349822 A JP2006349822 A JP 2006349822A JP 2006349822 A JP2006349822 A JP 2006349822A JP 5122809 B2 JP5122809 B2 JP 5122809B2
- Authority
- JP
- Japan
- Prior art keywords
- lithium
- lithium fluoride
- fluoride
- weight
- hydrofluoric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
Description
本発明は、酸素濃度が低く、粒径の大きな粉体流動性にすぐれたフッ化リチウムを製造する方法に関するものである。 The present invention relates to a method for producing lithium fluoride having a low oxygen concentration and a large particle size and excellent powder flowability.
フッ化リチウムは、波長０．１０５〜６μｍの光に対して透明で、しかも２．５〜６．０μｍの波長領域の赤外光に対しては特に屈折率の分散が大きい。そのため、フッ化リチウム単結晶は、波長１３００〜２０００Åの領域の紫外分光測定用としても利用されている。 Lithium fluoride is transparent to light with a wavelength of 0.105 to 6 μm, and has a particularly large refractive index dispersion for infrared light with a wavelength region of 2.5 to 6.0 μm. Therefore, the lithium fluoride single crystal is also used for ultraviolet spectroscopic measurement in the wavelength region of 1300 to 2000 nm.
また、フッ化リチウムは、有機物質の蛍光（ルミネッセンス）現象を発光素子として応用した有機ＥＬ素子にも注目されている。具体的には、有機膜と接合性に優れた材料として、フッ化リチウム膜を真空蒸着することが検討されている（特許文献１参照）。 Lithium fluoride is also attracting attention as an organic EL element in which the fluorescence phenomenon of organic substances is applied as a light emitting element. Specifically, it has been studied to vacuum deposit a lithium fluoride film as a material excellent in bondability with an organic film (see Patent Document 1).
更に近年、高電圧、高エネルギー密度のリチウムイオン二次電池が開発され、携帯電話市場、パソコン等、携帯以外の中型リチウム電子市場等、その需要が急速に伸びている。さらに将来的には高性能な次世代ハイブリッド車向けに、ニッケル水素電池より小型で出力が大きいリチウムイオン二次電池の搭載が期待されている。フッ化リチウムは、リチウムイオン二次電池の電解質として使用される六フッ化リン酸リチウム（ＬｉＰＦ６）、ホウフッ化リチウム（ＬｉＢＦ４）等のリチウム塩の原料でもある。例えば、六フッ化リン酸リチウムの製造方法としては、無水フッ化水素中で五塩化リンとフッ化リチウムを反応させる方法（特許文献２参照）や、リンと金属ハロゲン化物粉末との混合物をフッ素ガスと反応させて、得られる高純度五フッ化リンを、フッ化リチウムと無水フッ化水素中で反応させる方法（特許文献３）が広く知られている。いずれも、原料としてフッ化リチウムが使用されている。 Further, in recent years, lithium ion secondary batteries with high voltage and high energy density have been developed, and the demand is rapidly increasing in the mobile phone market, personal computers, and other medium-sized lithium electronic markets other than mobile phones. In the future, it is expected that lithium-ion secondary batteries that are smaller and have a higher output than nickel metal hydride batteries will be installed in high-performance next-generation hybrid vehicles. Lithium fluoride is also a raw material for lithium salts such as lithium hexafluorophosphate (LiPF 6 ) and lithium borofluoride (LiBF 4 ) used as an electrolyte for lithium ion secondary batteries. For example, as a method for producing lithium hexafluorophosphate, a method in which phosphorus pentachloride and lithium fluoride are reacted in anhydrous hydrogen fluoride (see Patent Document 2), or a mixture of phosphorus and metal halide powder is fluorine. A method (Patent Document 3) in which a high purity phosphorus pentafluoride obtained by reacting with a gas is reacted in lithium fluoride and anhydrous hydrogen fluoride is widely known. In either case, lithium fluoride is used as a raw material.
フッ化リチウムの一般的な製法は、炭酸リチウムとフッ酸を直接反応させることによって得られる。しかし、炭酸リチウム、及びフッ化リチウムは、水、及び、濃度の薄いフッ酸への溶解度が極めて低いため、反応と同時に、非常に細かい粒子が析出する。さらに反応は非常に早く、激しいため、この細かい粒子同士が凝集を起こし、実際に得られる粒子は、１０μｍ程度に凝集したものが得られる。このように凝集が起こることで、未反応の炭酸リチウムが粒子内に取り込まれ、いくら高温及び／又は真空下で、乾燥を行っても、未反応炭酸リチウム由来の酸素成分を低減することが出来ない。さらに水溶液での合成系から分離されたフッ化リチウムは含水率が非常に大きく通常の乾燥方法では水分を１０００重量ｐｐｍ以下まで低減することは極めて困難であり、乾燥温度を高くするなどの工夫が必要である。 A general method for producing lithium fluoride is obtained by directly reacting lithium carbonate and hydrofluoric acid. However, since lithium carbonate and lithium fluoride have extremely low solubility in water and hydrofluoric acid having a low concentration, very fine particles are precipitated simultaneously with the reaction. Furthermore, since the reaction is very fast and intense, the fine particles are aggregated, and the actually obtained particles are aggregated to about 10 μm. As a result of such aggregation, unreacted lithium carbonate is taken into the particles, and oxygen components derived from unreacted lithium carbonate can be reduced no matter how high temperature and / or vacuum is dried. Absent. Furthermore, lithium fluoride separated from the synthesis system in an aqueous solution has a very high moisture content, and it is extremely difficult to reduce the water content to 1000 ppm by weight or less by a normal drying method. is necessary.
さらに従来のフッ化リチウムは比表面積が大きい粉末状であり吸湿性に富むため乾燥を行った後、保管中に空気中の水分を容易に吸湿してしまう。また、嵩密度が小さいものは、嵩張るため、同じ容積の容器に入る重量が少なくなるが、嵩密度が大きい場合はその逆で、製品や原料を入れるルツボ、ホッパーあるいはサイロを小型化でき経済上有利である。一方、安息角は、粉末のホーパーやサイロを設計する際に重要な因子になる。安息角が大きい粉末は、流動性が悪く、ホッパー内でブリッジを起こし易い。つまりホッパーやサイロの底部の傾斜を中の粉末の安息角よりも大きくしなければ、内部の粉末は完全には排出されない。逆に安息角の小さな粉末は流動性がよく、ホッパー内でのブリッジ等のトラブルが発生しにくく、且つ、ホッパーやサイロを小型化でき経済上有利である。 Furthermore, since conventional lithium fluoride is in the form of a powder having a large specific surface area and is highly hygroscopic, moisture in the air is easily absorbed during storage after drying. In addition, those with a low bulk density are bulky, so that the weight entering the container of the same volume is reduced. However, when the bulk density is high, the opposite is true, and the crucible, hopper, or silo for storing products and raw materials can be downsized. It is advantageous. On the other hand, the angle of repose is an important factor in designing powder hoppers and silos. A powder having a large angle of repose has poor flowability and tends to cause bridging in the hopper. That is, unless the inclination of the bottom of the hopper or silo is made larger than the angle of repose of the powder inside, the powder inside is not completely discharged. Conversely, powder with a small angle of repose has good fluidity, is less likely to cause troubles such as bridging in the hopper, and can be economically advantageous because the hopper and silo can be downsized.
その結果、フッ化リチウム単結晶の成長の際に、結晶中に酸素成分が混入し、結晶が白濁する等の問題がある。また、有機ＥＬ素子に使用した場合には、真空蒸着によるフッ化リチウム膜の成膜の際に、フッ化リチウム膜が酸化され、これにより、有機ＥＬ素子の寿命が低下するという問題がある。更に、空隙率が大きいため、成膜速度が低く、かつ蒸着るつぼに電子ビームが当り、蒸着膜であるフッ化リチウム膜に不純物が混入する等の問題もある。リチウムイオン二次電池の電解質として使用する場合には、原料中の水分や酸素成分と五フッ化リンが反応し、その生成物がオキシフッ化リン（ＰＯＦ３）とフッ化水素（ＨＦ）等に分解して製品内に混入することがある。これらは、電池反応を阻害するため、好ましくない。更に、これらが電池内に組み込まれた場合、電池が膨張し、重大な問題を引き起こす可能性がある。 As a result, when the lithium fluoride single crystal is grown, there is a problem that an oxygen component is mixed in the crystal and the crystal becomes cloudy. Moreover, when it uses for an organic EL element, when forming the lithium fluoride film | membrane by vacuum evaporation, there exists a problem that a lithium fluoride film | membrane is oxidized and this reduces the lifetime of an organic EL element. Furthermore, since the porosity is large, there are also problems such as a low film formation speed, an electron beam hitting the vapor deposition crucible, and impurities mixing into the lithium fluoride film as the vapor deposition film. When used as an electrolyte of a lithium ion secondary battery, moisture and oxygen components in the raw material react with phosphorus pentafluoride, and the product becomes phosphorus oxyfluoride (POF 3 ), hydrogen fluoride (HF), etc. May be decomposed and mixed into the product. These are not preferable because they inhibit the battery reaction. Furthermore, if they are incorporated into the battery, the battery can swell and cause serious problems.
一方、下記特許文献４には、アルカリフッ化物の製造方法が開示されている。この製造方法によれば、フッ酸・フッ化アンモニウムを用いて、酸化物不純物の少ない（＜１０重量ｐｐｍ）フッ化リチウムやフッ化ナトリウムを製造する旨の記載がある。更に、製造したフッ化リチウムの酸素濃度に関し、１０ｐｐｍ程度のものが得られた旨の記載がある（段落［００２５］）。しかし、この値は、フッ化物ガラス中の酸素濃度であり、乾燥後の値ではない。即ち、高温で溶融させた後（ガラス中）の酸素濃度である。 On the other hand, Patent Document 4 below discloses a method for producing an alkali fluoride. According to this production method, there is a description that lithium fluoride or sodium fluoride with less oxide impurities (<10 ppm by weight) is produced using hydrofluoric acid / ammonium fluoride. Furthermore, there is a description that about 10 ppm of the produced lithium fluoride was obtained (paragraph [0025]). However, this value is the oxygen concentration in the fluoride glass, not the value after drying. That is, the oxygen concentration after melting at high temperature (in the glass).
さらに粒度の大きなフッ化カルシウムの回収方法として、下記特許文献５が報告されている。この方法によれば、ｐＨ２以下の塩酸酸性条件下で、フッ素含有排液と塩化カルシウム水溶液との反応により、純度が高く、粒度の大きなフッ化カルシウムを効果的に回収出来ると記されている。しかし、この公報によればｐＨ２以下でなければ大きな粒径のフッ化カルシウムを得ることが出来ないことになる。 Further, Patent Document 5 below has been reported as a method for recovering calcium fluoride having a larger particle size. According to this method, it is described that calcium fluoride having a high purity and a large particle size can be effectively recovered by the reaction between the fluorine-containing effluent and the aqueous calcium chloride solution under acidic conditions of hydrochloric acid of pH 2 or lower. However, according to this publication, calcium fluoride having a large particle size cannot be obtained unless the pH is 2 or less.
またこの公報では、［００３８］濃厚なフッ酸含有排液を処理する場合には、フッ酸含有排液と塩化カルシウム水溶液の反応で流出した溶液および脱水後の濾液を用いて、濃厚なフッ酸含有排液を希釈するとよい。との記載がある。さらに実施例においても、フッ酸の濃度の最大値は１７．２重量％となっている。一般的に希釈された液を反応させることで粒径を大きくすることが可能となる。この公報或いはフッ素含有排水からフッ素を除去する方法などでは、薄い濃度のフッ酸が用いられており、２０重量％以上、もしくは５０重量％程度の非常に濃いフッ酸との反応で、粒径の大きなものを得る報告はされていない。 In addition, in this publication, when processing a concentrated hydrofluoric acid-containing effluent, a concentrated hydrofluoric acid is used by using a solution effluent from the reaction between the hydrofluoric acid-containing effluent and an aqueous calcium chloride solution and a filtrate after dehydration. The contained effluent should be diluted. There is a description. Furthermore, also in the examples, the maximum value of the concentration of hydrofluoric acid is 17.2% by weight. In general, the particle size can be increased by reacting a diluted liquid. In this publication or a method for removing fluorine from fluorine-containing wastewater, etc., a thin concentration of hydrofluoric acid is used. The reaction with a very concentrated hydrofluoric acid of 20% by weight or more, or about 50% by weight, There has been no report of getting a big one.
本発明は前記問題点に鑑みなされたものであり、その目的は、粒径が大きく乾燥後の酸素濃度が低く、取り扱い性に優れたフッ化リチウムの製造方法を提供することにある。一般的に粒径を大きくするためには、希釈された系で反応を行うことが望ましいが、希釈系で反応を行う場合、反応装置が非常に大きくなってしまう。そこで工業化も加味し、２０重量％以上、もしくは５０重量％程度の高濃度領域で、乾燥後の酸素濃度が低く、粒径の大きなフッ化リチウムを製造する。 The present invention has been made in view of the above problems, and an object thereof is to provide a method for producing lithium fluoride having a large particle size, a low oxygen concentration after drying, and excellent handleability. In general, in order to increase the particle size, it is desirable to perform the reaction in a diluted system. However, when the reaction is performed in a diluted system, the reaction apparatus becomes very large. Therefore, in consideration of industrialization, lithium fluoride having a large particle size is produced in a high concentration region of about 20% by weight or about 50% by weight with a low oxygen concentration after drying.
本願発明者等は、前記従来の問題点を解決すべく、フッ化リチウムの製造方法について検討した。その結果、下記の方法を採用することにより前記目的を達成できることを見出して、本発明を完成させるに至った。 The inventors of the present application have studied a method for producing lithium fluoride in order to solve the conventional problems. As a result, it has been found that the object can be achieved by employing the following method, and the present invention has been completed.
本発明のフッ化リチウムの製造方法は、炭酸リチウム、水酸化リチウム、硝酸リチウム、塩化リチウム、及び硫酸リチウムからなる群より選択される少なくとも何れか１種のリチウム化合物の濃度が１０〜５０重量％であるリチウム塩溶液を作製し、前記リチウム塩溶液に対し、１０重量％以上６０重量％以下のフッ酸を１〜５モル当量の割合で、リチウム塩溶液及びフッ酸を反応器に同時滴下しながら反応させ、安息角が５０度以下、且つ、嵩密度が０．７５ｇ／ｃｍ３以上のフッ化リチウムを作製するものである。 In the method for producing lithium fluoride of the present invention, the concentration of at least one lithium compound selected from the group consisting of lithium carbonate, lithium hydroxide, lithium nitrate, lithium chloride, and lithium sulfate is 10 to 50% by weight. A lithium salt solution is prepared, and 10 wt% to 60 wt% hydrofluoric acid is added dropwise to the reactor at a rate of 1 to 5 molar equivalents simultaneously in the reactor. Thus, lithium fluoride having an angle of repose of 50 degrees or less and a bulk density of 0.75 g / cm 3 or more is produced.
本発明は、前記濃度範囲のリチウム塩溶液及びフッ酸を同時滴下で反応させることにより、安息角５０度以下、嵩密度０．７５ｇ／ｃｍ３以上のフッ化リチウムの製造が可能になる。安息角が５０度以下のフッ化リチウムが得られることにより、含水率を低下させ、平均粒径が大きく、粉体流動性の良好なフッ化リチウムが得られる。また、嵩密度が０．７５ｇ／ｃｍ３以上のフッ化リチウムが得られることにより、吸湿性を抑制してその後の乾燥処理を容易なものにする。また、フッ化リチウムを入れるルツボ、ホッパーあるいはサイロを小型化できる。その結果、製造コストを抑制して、取扱い性に優れたフッ化リチウムを製造することができる。 According to the present invention, lithium fluoride having a repose angle of 50 degrees or less and a bulk density of 0.75 g / cm 3 or more can be produced by reacting the lithium salt solution and hydrofluoric acid in the above concentration range by simultaneous dropping. By obtaining lithium fluoride having an angle of repose of 50 ° or less, lithium fluoride can be obtained which has a reduced moisture content, a large average particle size and good powder flowability. Further, by obtaining lithium fluoride having a bulk density of 0.75 g / cm 3 or more, the hygroscopic property is suppressed and the subsequent drying treatment is facilitated. In addition, the crucible, hopper, or silo that contains lithium fluoride can be downsized. As a result, it is possible to manufacture lithium fluoride that is excellent in handleability while suppressing manufacturing costs.
前記リチウム塩溶液は、前記炭酸リチウム、水酸化リチウム、硝酸リチウム、塩化リチウム、及び硫酸リチウムからなる群より選択される少なくとも何れか１種のリチウム化合物を、硝酸、塩酸、硫酸、及び水からなる群より選択される少なくとも何れか１種に溶解させて得られるものであることが好ましい。 The lithium salt solution includes at least one lithium compound selected from the group consisting of lithium carbonate, lithium hydroxide, lithium nitrate, lithium chloride, and lithium sulfate, and includes nitric acid, hydrochloric acid, sulfuric acid, and water. It is preferably obtained by dissolving in at least one selected from the group.
前記リチウム塩溶液とフッ酸の同時滴下は、反応容量１ｍ３当たり１時間に１０ｋｇ以上５０００ｋｇ未満の速度により行うことが好ましい。 The simultaneous dropping of the lithium salt solution and hydrofluoric acid is preferably performed at a rate of 10 kg or more and less than 5000 kg per hour per 1 m 3 of reaction volume.
前記の方法に於いては、乾燥処理によりフッ化リチウムの酸素含有量を１０００重量ｐｐｍ以下にすることが好ましい。
It is In the above method, is to Rukoto the oxygen content of lithium fluoride below 1000 ppm by weight preferred by drying.
本発明は、前記に説明した手段により、以下に述べるような効果を奏する。
即ち、本発明のフッ化リチウムの製造方法によれば、安息角５０度以下、嵩密度０．７５ｇ／ｃｍ３以上で、酸素含有量の低いフッ化リチウムを製造できるので、例えば、フッ化リチウム単結晶、有機ＥＬ素子のフッ化リチウム膜、リチウムイオン二次電池の電解質用原料としての性能向上が可能になる。
The present invention has the following effects by the means described above.
That is, according to the method for producing lithium fluoride of the present invention, lithium fluoride having a repose angle of 50 degrees or less, a bulk density of 0.75 g / cm 3 or more and a low oxygen content can be produced. The performance as a raw material for electrolyte of a single crystal, a lithium fluoride film of an organic EL element, or a lithium ion secondary battery can be improved.
本発明に係るフッ化リチウムの製造方法は、それぞれ所定濃度のリチウム塩溶液及びフッ酸を、反応器に同時滴下しながら反応させて行う。 In the method for producing lithium fluoride according to the present invention, a lithium salt solution and hydrofluoric acid having a predetermined concentration are reacted while being simultaneously dropped into a reactor.
前記リチウム塩溶液は、炭酸リチウム、水酸化リチウム、硝酸リチウム、塩化リチウム、及び硫酸リチウムからなる群より選択される少なくとも何れか１種のリチウム化合物を、硝酸、塩酸、硫酸、及び水からなる群より選択される少なくとも何れか１種に溶解させて得られるものが好ましい。また、リチウム塩溶液は、市販の物をそのまま使用してもよい。 The lithium salt solution includes at least one lithium compound selected from the group consisting of lithium carbonate, lithium hydroxide, lithium nitrate, lithium chloride, and lithium sulfate, and a group consisting of nitric acid, hydrochloric acid, sulfuric acid, and water. Those obtained by dissolving in at least one selected from the above are preferred. A commercially available lithium salt solution may be used as it is.
前記リチウム塩溶液に於けるリチウム化合物の濃度は１０〜５０重量％であり、好ましくは２０〜３０重量％、より好ましくは２５〜３０重量％である。また、フッ酸の濃度は１０〜６０重量％であり、好ましくは４０〜６０重量％、より好ましくは５０〜５５重量％である。リチウム塩溶液及びフッ酸の濃度が低すぎると、反応槽が大きくなり不経済である。その一方、濃度が濃すぎると、得られるフッ化リチウムの平均粒径及び嵩密度が小さくなり、かつ、安息角が大きくなるため好ましくない。 The concentration of the lithium compound in the lithium salt solution is 10 to 50% by weight, preferably 20 to 30% by weight, more preferably 25 to 30% by weight. The concentration of hydrofluoric acid is 10 to 60% by weight, preferably 40 to 60% by weight, and more preferably 50 to 55% by weight. If the concentration of the lithium salt solution and hydrofluoric acid is too low, the reaction tank becomes large and uneconomical. On the other hand, if the concentration is too high, the average particle diameter and bulk density of the resulting lithium fluoride are decreased, and the angle of repose is increased, which is not preferable.
リチウム化合物の溶解に使用する前記水としては特に限定されず、金属不純物の混入していないものが好ましい。より具体的には、蒸留水、純水、超純水、イオン交換水等が挙げられる。 The water used for dissolving the lithium compound is not particularly limited, and preferably water that is not mixed with metal impurities. More specifically, distilled water, pure water, ultrapure water, ion-exchanged water and the like can be mentioned.
また、リチウム化合物を酸に溶解させる場合、当該酸の濃度は特に限定されないが、一定濃度以上になると白濁する場合がある。従って、酸の濃度としては、７０重量％以下であることが好ましく、５０重量％未満であることがより好ましく、３５重量％以下であることが特に好ましい。また、酸の添加モル倍率は、リチウム化合物に対して５倍以下が好ましく、１．２倍以下がより好ましく、１．１倍以下が更に好ましく、１．０７倍以下が特に好ましい。 In addition, when the lithium compound is dissolved in an acid, the concentration of the acid is not particularly limited, but may become cloudy when the concentration exceeds a certain level. Accordingly, the acid concentration is preferably 70% by weight or less, more preferably less than 50% by weight, and particularly preferably 35% by weight or less. The acid addition molar ratio is preferably 5 times or less, more preferably 1.2 times or less, still more preferably 1.1 times or less, and particularly preferably 1.07 times or less with respect to the lithium compound.
リチウム塩溶液のｐＨについては特に範囲は限定されないが、弱酸性〜中性〜弱アルカリ性領域で行うことが好ましい。より具体的には、ｐＨ３〜１２が好ましく、より好ましくはｐＨ５〜１０、さらに好ましくはｐＨ８〜１０である。ｐＨが３未満であると、過剰の酸を使用することになり製造コストの抑制が図れない。その一方、ｐＨが１２を超えると、過剰のアルカリを使用することになり製造コストの抑制が図れない。また、リチウム塩溶液が空気中の炭酸ガスを吸収して炭酸塩を生成し、製造装置に於ける閉塞等のトラブルが発生する為好ましくない。 The range of the pH of the lithium salt solution is not particularly limited, but it is preferably performed in a weakly acidic to neutral to weakly alkaline region. More specifically, pH 3-12 is preferable, pH 5-10 is more preferable, and pH 8-10 is more preferable. If the pH is less than 3, excess acid is used, and the production cost cannot be reduced. On the other hand, when the pH exceeds 12, excess alkali is used, and the production cost cannot be suppressed. In addition, the lithium salt solution absorbs carbon dioxide in the air to produce carbonate, which is not preferable because troubles such as clogging in the manufacturing apparatus occur.
前記フッ酸については、グレードは特に限定されるものではなく、市販の工業用グレード・一般グレード・半導体グレード等がそのまま、あるいは適宜濃度調整して使用できる。その中でも、不純物量の少ない半導体グレードの使用が好ましいが、コストの面からは、工業用グレード・一般グレード等が特に好ましい。不純物濃度としては、各金属不純物が１重量ｐｐｍ以下であれば十分である。 As for the hydrofluoric acid, the grade is not particularly limited, and commercially available industrial grades, general grades, semiconductor grades, etc. can be used as they are or after adjusting the concentration appropriately. Among them, the use of a semiconductor grade with a small amount of impurities is preferable, but industrial grade, general grade, and the like are particularly preferable from the viewpoint of cost. As the impurity concentration, it is sufficient that each metal impurity is 1 ppm by weight or less.
リチウム塩溶液に対するフッ酸の添加割合は１モル当量以上５モル当量以下が好ましく、１モル当量以上３モル当量以下がより好ましく、１．０１モル当量以上２モル当量未満が更に好ましく、１．０１モル当量以上１．５モル当量未満が特に好ましい。１モル当量以上５モル当量以下とすることにより、フッ化リチウムを安定した収量で得られる。但し、１〜３モル当量以下とすることにより、フッ酸の消費量を極力抑制できると共に、得られるフッ化リチウムの安息角を一層小さくし、嵩密度及び粒径を一層大きくすることができる。 The addition ratio of hydrofluoric acid to the lithium salt solution is preferably 1 to 5 molar equivalents, more preferably 1 to 3 molar equivalents, still more preferably 1.01 to 2 molar equivalents, and 1.01 The molar equivalent is more preferably less than 1.5 molar equivalent. By setting it to 1 to 5 molar equivalents, lithium fluoride can be obtained in a stable yield. However, by setting it to 1 to 3 molar equivalents or less, the consumption of hydrofluoric acid can be suppressed as much as possible, the angle of repose of the obtained lithium fluoride can be further reduced, and the bulk density and particle size can be further increased.
また、本発明を実施するに当たって、リチウム塩溶液及びフッ酸は、それぞれ高純度に精製されたものを用いるのが好ましい。高純度に精製されたリチウム塩溶液が入手できない場合は、粗リチウム塩溶液を精製して用いてもよい。リチウム塩溶液の精製法については一般的な方法として、晶析法、イオン交換法等の公知技術が使用できる。金属不純物については水酸化物沈殿法、硫酸根については硫酸バリウムとして沈殿除去する方法も有効である。なお、反応系における水溶性の不純物については反応液から生成した固体のフッ化リチウムを分離する際に大部分は液側に移行するために、その固液分離操作だけで精製効果がある場合もある。このようにして調整されたリチウム塩溶液は、適時濃度を調整するために、金属不純物の混入していない水、例えば、蒸留水・純水・超純水・イオン交換水などによって希釈しても構わない。 In carrying out the present invention, it is preferable to use a lithium salt solution and hydrofluoric acid that have been purified to a high purity. If a highly purified lithium salt solution is not available, the crude lithium salt solution may be purified and used. As a general method for purifying the lithium salt solution, known techniques such as a crystallization method and an ion exchange method can be used. It is also effective to use a hydroxide precipitation method for metal impurities and a method for precipitation removal as sulfate for barium sulfate. Note that most of the water-soluble impurities in the reaction system move to the liquid side when the solid lithium fluoride produced from the reaction solution is separated, so there may be a purification effect only by the solid-liquid separation operation. is there. The lithium salt solution thus prepared may be diluted with water not contaminated with metal impurities, for example, distilled water, pure water, ultrapure water, ion-exchanged water, etc., in order to adjust the concentration in a timely manner. I do not care.
反応槽への原料の供給方法については、本発明はリチウム塩溶液とフッ酸とを同時滴下する。当該方法でのみ、安息角が５０度以下、且つ、嵩密度が０．７５ｇ／ｃｍ３以上であり、しかも中心粒径が５０μｍ以上（好ましくは１００μｍ以上）の粉体流動性にすぐれたフッ化リチウムが得られる。更に、リチウム塩溶液とフッ酸の両方を予め反応槽に仕込んでおき、その後リチウム塩溶液とフッ酸とを同時滴下してもよい。一方、フッ酸にリチウム塩溶液を滴下する方法、又はリチウム塩溶液にフッ酸を滴下する方法では、安息角が５０度以下、且つ、嵩密度が０．７５ｇ／ｃｍ３以上であり、中心粒径が５０μｍ以上の粉体流動性にすぐれたフッ化リチウムを得ることは困難である。 Regarding the method of supplying the raw material to the reaction vessel, the present invention simultaneously drops a lithium salt solution and hydrofluoric acid. Only by this method, fluorination having an angle of repose of 50 degrees or less, a bulk density of 0.75 g / cm 3 or more, and a center particle size of 50 μm or more (preferably 100 μm or more) and excellent powder flowability. Lithium is obtained. Further, both the lithium salt solution and hydrofluoric acid may be previously charged in the reaction vessel, and then the lithium salt solution and hydrofluoric acid may be dropped simultaneously. On the other hand, in the method of dropping a lithium salt solution into hydrofluoric acid or the method of dropping hydrofluoric acid into a lithium salt solution, the angle of repose is 50 degrees or less, the bulk density is 0.75 g / cm 3 or more, It is difficult to obtain lithium fluoride having a diameter of 50 μm or more and excellent powder flowability.
リチウム塩溶液及びフッ酸の滴下速度は、反応容量１ｍ３当たり１時間に１０ｋｇ以上５０００ｋｇ未満であることが好ましく、５０ｋｇ以上２０００ｋｇ未満であればより好ましく、５０ｋｇ以上１０００ｋｇ未満であれば更に好ましく、５０ｋｇ以上５００ｋｇ未満であれば特に好ましい。滴下速度が反応容量１ｍ３当たり１時間に１０ｋｇ未満であると、フッ化リチウムの生産性が低下し、コスト上昇に繋がる可能性がある。その一方、反応容量１ｍ３当たり１時間に５０００ｋｇ以上であると、リチウム塩溶液及びフッ酸の供給に、大きな動力が必要となり製造コストの増大を招来する恐れがある。 The dropping rate of the lithium salt solution and hydrofluoric acid is preferably 10 kg or more and less than 5000 kg per hour per 1 m 3 of the reaction volume, more preferably 50 kg or more and less than 2000 kg, more preferably 50 kg or more and less than 1000 kg, and even more preferably 50 kg. If it is more than 500 kg, it is especially preferable. If the dropping rate is less than 10 kg per hour per 1 m 3 of reaction volume, the productivity of lithium fluoride may be reduced, leading to an increase in cost. On the other hand, if the reaction capacity is 5000 kg or more per 1 m 3 , a large power is required for supplying the lithium salt solution and hydrofluoric acid, which may increase the production cost.
尚、滴下速度については、反応容量が大きい場合はそれに応じて滴下速度を速めればよく、小さい場合は滴下速度を遅くすればよい。これにより、上記の操作が実現できる。例えば、反応容量が０．１ｍ３であれば、それに応じて１時間に１ｋｇ以上、５００ｋｇ未満の速度で反応器に同時滴下すればよい。 Regarding the dropping rate, when the reaction volume is large, the dropping rate may be increased accordingly, and when it is small, the dropping rate may be decreased. Thereby, said operation is realizable. For example, if the reaction volume is 0.1 m 3 , it may be simultaneously dropped into the reactor at a rate of 1 kg or more and less than 500 kg per hour accordingly.
リチウム塩溶液及びフッ酸の滴下時間は、特に限定されるものではないが、０．２〜２４時間が好ましく、０．３〜６時間がより好ましく、０．５〜４時間が更に好ましい。生産性を考慮した場合、０．５〜２時間で投入するのが特に好ましい。 The dropping time of the lithium salt solution and hydrofluoric acid is not particularly limited, but is preferably 0.2 to 24 hours, more preferably 0.3 to 6 hours, and still more preferably 0.5 to 4 hours. In consideration of productivity, it is particularly preferable to input in 0.5 to 2 hours.
反応の際には攪拌を行なうのが好ましいが、攪拌の程度は特に限定されない。しかし、撹拌速度が０．５ｍ／秒未満であると、反応槽内でフッ化リチウムが底部に沈降し、閉塞等のトラブルを生じる場合がある。また、２ｍ／秒を越えると、攪拌に要する動力が大きくなり製造コストが増大する。このため、攪拌の程度は攪拌羽根の先端の周速として０．５ｍ／秒〜２ｍ/秒が好ましい。 Stirring is preferably performed during the reaction, but the degree of stirring is not particularly limited. However, if the stirring speed is less than 0.5 m / sec, lithium fluoride may settle to the bottom in the reaction vessel, causing troubles such as clogging. On the other hand, if it exceeds 2 m / sec, the power required for stirring increases and the production cost increases. For this reason, the degree of stirring is preferably 0.5 m / second to 2 m / second as the peripheral speed at the tip of the stirring blade.
反応・熟成時間も特に限定されないが、短い場合は収率が低下する可能性がある。一方、長い場合は生産性が低下する。そのため、反応・熟成時間として、０．５時間以上１２時間未満、好ましくは１時間以上１０時間未満、さらに好ましくは１．５時間以上８時間未満、その中でも特に好ましくは２時間以上５時間未満である。 The reaction / ripening time is also not particularly limited, but if it is short, the yield may decrease. On the other hand, if the length is long, the productivity decreases. Therefore, the reaction / ripening time is 0.5 to 12 hours, preferably 1 to 10 hours, more preferably 1.5 to 8 hours, and particularly preferably 2 to 5 hours. is there.
同時滴下時、熟成時、濾過、洗浄時の温度も特に限定されるものではないが、低温ほど収率が向上するものの、生産性の面でコスト上昇に繋がる。そのため、好ましくは０℃以上９０℃未満、さらに好ましくは１０℃以上６０℃未満、その中でも特に好ましくは１５℃以上５０℃未満である。 The temperature at the time of simultaneous dripping, aging, filtration, and washing is not particularly limited, but the yield increases as the temperature decreases, but the cost increases in terms of productivity. Therefore, it is preferably 0 ° C. or higher and lower than 90 ° C., more preferably 10 ° C. or higher and lower than 60 ° C., and particularly preferably 15 ° C. or higher and lower than 50 ° C.
上記の一連の操作で得られるフッ化リチウムは固液分離される。固液分離の方法としては濾過方法が挙げられ、濾過方法としては、自然濾過、加圧濾過、遠心分離濾過等が挙げられる。 The lithium fluoride obtained by the above series of operations is subjected to solid-liquid separation. Examples of the solid-liquid separation method include a filtration method, and examples of the filtration method include natural filtration, pressure filtration, and centrifugal filtration.
固液分離後は、洗浄操作により、フッ化リチウムの純度を高めるのが好ましい。洗浄操作としては、フッ化リチウムを再度洗浄剤に分散させて行う方法、分離装置内に直接洗浄剤を導入し、フッ化リチウムと接触させて行う方法など公知の方法を単独で、あるいは組み合わせて行うことができる。また、濾過後のろ液には、余剰のリチウム塩溶液、又は酸が多量に含まれている場合がある。この場合、ろ液に対し蒸留等を行い、リチウム塩溶液、又は酸を回収すれば、廃水処理の負荷削減によるコスト低減と有価物の回収で２重の効果をあげることができる。 After the solid-liquid separation, it is preferable to increase the purity of lithium fluoride by a washing operation. As the washing operation, a known method such as a method in which lithium fluoride is dispersed again in a cleaning agent, a method in which a cleaning agent is directly introduced into a separation apparatus and contacted with lithium fluoride is used alone or in combination. It can be carried out. Moreover, the filtrate after filtration may contain a large amount of excess lithium salt solution or acid. In this case, if the filtrate is subjected to distillation or the like and the lithium salt solution or the acid is recovered, a double effect can be obtained by reducing the cost of wastewater treatment and recovering valuable materials.
固液分離により得られたフッ化リチウムは乾燥するのが好ましい。乾燥方法としては、風乾、温熱乾燥、真空乾燥等が挙げられる。乾燥時間は、特に限定されないが、一般には０．５〜７２時間である。乾燥温度は２００℃未満で行うのが好ましい。２００℃以上の温度で行うと、フッ化リチウムの乾燥ではなく焙焼又は溶融になるからである。更に、２００℃以上の温度で行うと、乾燥設備が高価になり、大きな熱量が必要となり製造コスト高となる。 Lithium fluoride obtained by solid-liquid separation is preferably dried. Examples of the drying method include air drying, heat drying, and vacuum drying. The drying time is not particularly limited, but is generally 0.5 to 72 hours. The drying temperature is preferably less than 200 ° C. This is because, when performed at a temperature of 200 ° C. or higher, lithium fluoride is not dried but roasted or melted. Furthermore, if it is performed at a temperature of 200 ° C. or higher, the drying equipment becomes expensive, a large amount of heat is required, and the production cost is increased.
従来の製造方法により得られるフッ化リチウムでは、粒径が小さく凝集しているため、付着・吸着水分を除去するのに、相当量の熱量を必要とする。しかも、水分が取り込まれた形で凝集されて、水分が残存する為、乾燥温度が低い場合には、水分除去が不十分になる。その一方、乾燥温度を高くすると、粒子中で水により加水分解したフッ化リチウムが酸化リチウムとなり、酸素成分が多く残留する。この場合、有機ＥＬ素子のフッ化リチウム膜に適用すると、光学性能に悪影響を与える。 Since lithium fluoride obtained by a conventional production method has a small particle size and agglomerates, a considerable amount of heat is required to remove adhering / adsorbed moisture. In addition, the water is agglomerated in a form in which water is taken in, and the water remains. Therefore, when the drying temperature is low, water removal is insufficient. On the other hand, when the drying temperature is raised, lithium fluoride hydrolyzed with water in the particles becomes lithium oxide, and a large amount of oxygen component remains. In this case, when applied to the lithium fluoride film of the organic EL element, the optical performance is adversely affected.
これに対し、本発明で得られるフッ化リチウムは粒径が大きいため、乾燥処理が容易で、乾燥時に要する熱量も少なくて済む。このため、製造コストを一層低減できる。しかも、本発明の製造方法で得られるフッ化リチウムは、粒子構造中に取り込まれる水分が少なく、焙焼・溶融操作を行わなくとも乾燥処理だけで足りる。更に、フッ化リチウム中の残留酸素成分も１０００重量ｐｐｍ以下、更に５００重量ｐｐｍ以下、特に１００重量ｐｐｍ以下まで低減することができ、用途上非常に良好なものとなる。従って、フッ化リチウム単結晶、有機ＥＬ素子のフッ化リチウム膜、リチウムイオン二次電池の電解質用原料として、従来のフッ化リチウムよりもより品質の高い優れた製品の製造が可能となる。 On the other hand, since the lithium fluoride obtained by the present invention has a large particle size, the drying process is easy and the amount of heat required for drying is small. For this reason, manufacturing cost can be further reduced. Moreover, the lithium fluoride obtained by the production method of the present invention has a small amount of moisture taken into the particle structure, and only a drying process is sufficient without performing roasting and melting operations. Furthermore, the residual oxygen component in the lithium fluoride can be reduced to 1000 ppm by weight or less, further 500 ppm by weight or less, and particularly 100 ppm by weight or less, which is very good for use. Accordingly, it is possible to manufacture an excellent product having higher quality than conventional lithium fluoride as a lithium fluoride single crystal, a lithium fluoride film of an organic EL element, and a raw material for electrolyte of a lithium ion secondary battery.
以下に、この発明の好適な実施例を例示的に詳しく説明する。但し、この実施例に記載されている材料や配合量等は、特に限定的な記載がない限りは、この発明の範囲をそれらのみに限定する趣旨のものではなく、単なる説明例に過ぎない。 Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in the examples are not intended to limit the scope of the present invention only to them, but are merely illustrative examples, unless otherwise specified.
（実施例１）
炭酸リチウム７４ｇを４０重量％硝酸４７３ｇに加えて、攪拌溶解を行い、ｐＨ５の硝酸リチウム溶液を作製した。続いて、フッ素樹脂製反応槽を０℃氷浴により冷却しながら、半導体グレードの５０重量％フッ酸１５８ｇと前記硝酸リチウム溶液を、０．８ｍ／秒の攪拌速度で、全量に対し１００ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、８時間の攪拌を行った。
Example 1
74 g of lithium carbonate was added to 473 g of 40 wt% nitric acid and dissolved by stirring to prepare a lithium nitrate solution having a pH of 5. Subsequently, while cooling the fluororesin reaction tank with a 0 ° C. ice bath, 158 g of semiconductor grade 50 wt% hydrofluoric acid and the lithium nitrate solution were added at 100 g / L with respect to the total amount at a stirring speed of 0.8 m / sec. -Simultaneous dripping was performed so that the dripping speed of Hr was obtained. Further, stirring was performed for 8 hours.
次に、得られた沈殿物を吸引濾過により濾別した。回収した結晶を水で繰り返し洗浄し、その後、１０５℃で６時間乾燥した。得られた結晶の収量は４９．２ｇ（収率９５％）であった。 Next, the obtained precipitate was separated by suction filtration. The recovered crystals were washed repeatedly with water and then dried at 105 ° C. for 6 hours. The yield of the obtained crystal was 49.2 g (yield 95%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ、０．９２ｇ／ｃｍ３であった。また、安息角を測定したところ４３度であり、平均粒径は８０μｍであった。更に、１０５℃で２４時間乾燥後のフッ化リチウム中の酸素濃度は１３０重量ｐｐｍであった。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.92 g / cm 3 . Further, the angle of repose was measured and found to be 43 degrees, and the average particle size was 80 μm. Furthermore, the oxygen concentration in lithium fluoride after drying for 24 hours at 105 ° C. was 130 ppm by weight.
尚、嵩密度は、静置法法（ＪＩＳ Ｋ５１０１−１２−１）により測定した。また、安息角は、注入法により測定した。更に、平均粒径は、粒度分布測定器により測定した。また、フッ化リチウム中の酸素濃度は、酸素分析装置により測定した。 The bulk density was measured by a stationary method (JIS K5101-12-1). The angle of repose was measured by the injection method. Furthermore, the average particle diameter was measured with a particle size distribution measuring instrument. The oxygen concentration in lithium fluoride was measured with an oxygen analyzer.
（実施例２）
水酸化リチウム８４ｋｇを２９重量％硫酸８５１ｋｇに加えて、攪拌溶解を行い、ｐＨ３の硫酸リチウム溶液を作製した。続いて、フッ素樹脂でライニングした反応槽を６０℃に保ち、半導体グレードの５０重量％フッ酸１５８ｋｇと前記硫酸リチウム溶液を、１ｍ／秒の攪拌速度で、全量に対し５０ｋｇ／ｍ３・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、６時間の攪拌を行った。
(Example 2)
84 kg of lithium hydroxide was added to 851 kg of 29 wt% sulfuric acid and dissolved by stirring to prepare a pH 3 lithium sulfate solution. Subsequently, the reaction vessel lined with a fluororesin was maintained at 60 ° C., and 158 kg of semiconductor grade 50 wt% hydrofluoric acid and the lithium sulfate solution were mixed at a stirring speed of 1 m / sec with 50 kg / m 3 · Hr of the total amount. Simultaneous dropping was performed so as to obtain a dropping speed. Further, stirring was performed for 6 hours.
次に、得られた沈殿物を遠心濾過により濾別した。回収した結晶を水で繰り返し洗浄し、その後、１０５℃で６時間乾燥した。得られた結晶の収量は４８．４ｋｇ（収率９３％）であった。 Next, the obtained precipitate was separated by centrifugal filtration. The recovered crystals were washed repeatedly with water and then dried at 105 ° C. for 6 hours. The yield of the obtained crystal was 48.4 kg (yield 93%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ、０．８３ｇ／ｃｍ３であった。また、安息角を測定したところ４９度であり、平均粒径は６０μｍであった。更に、１０５℃で１２時間乾燥後の得られたフッ化リチウム中の酸素濃度は３５０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.83 g / cm 3 . Further, the angle of repose was measured to be 49 degrees, and the average particle size was 60 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 12 hours was 350 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例３）
塩化リチウム８５ｇを純水２１０ｇに加えて、攪拌溶解を行い、ｐＨ７の塩化リチウム水溶液を作製した。続いて、フッ素樹脂製反応槽を２５℃に保ち、半導体グレードの５０重量％フッ酸１５８ｇと前記塩化リチウム水溶液を、２ｍ／秒の攪拌速度で、全量に対し１５０ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、９時間の攪拌を行った。
(Example 3)
85 g of lithium chloride was added to 210 g of pure water and dissolved by stirring to prepare a pH 7 lithium chloride aqueous solution. Subsequently, the reaction vessel made of fluororesin was kept at 25 ° C., and 158 g of semiconductor grade 50 wt% hydrofluoric acid and the lithium chloride aqueous solution were added at a stirring speed of 2 m / sec and a dropping rate of 150 g / L · Hr with respect to the total amount. Then, simultaneous dripping was performed. Furthermore, stirring was performed for 9 hours.
次に、得られた沈殿物を吸引濾過により濾別した。回収した結晶を水で繰り返し洗浄し、その後、１０５℃で６時間乾燥した。得られた結晶の収量は４６．９ｇ（収率９０％）であった。 Next, the obtained precipitate was separated by suction filtration. The recovered crystals were washed repeatedly with water and then dried at 105 ° C. for 6 hours. The yield of the obtained crystal was 46.9 g (90% yield).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ１．０２ｇ／ｃｍ３であった。また、安息角を測定したところ３８度であり、平均粒径は８０μｍであった。更に、１０５℃で８時間乾燥後のフッ化リチウム中の酸素濃度は１９０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 1.02 g / cm 3 . Further, the angle of repose was measured to be 38 degrees, and the average particle size was 80 μm. Furthermore, the oxygen concentration in lithium fluoride after drying at 105 ° C. for 8 hours was 190 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例４）
硝酸リチウム１４０ｇを３５重量％塩酸１１０ｇに加え、さらに超純水１００ｇを加え攪拌溶解を行い、ｐＨ５の硝酸リチウムの塩酸溶液を作製した。続いて、フッ素樹脂製反応槽を４５℃に保ち、半導体グレードの５０重量％フッ酸１０２ｇと硝酸リチウムの塩酸溶液を、０．５ｍ／秒の攪拌速度で、全量に対し２００ｇ／Ｌ・Ｈｒの滴下速度となるように同時滴下を行った。更に、８時間の攪拌を行った。
Example 4
140 g of lithium nitrate was added to 110 g of 35% by weight hydrochloric acid, and 100 g of ultrapure water was further added and dissolved by stirring to prepare a hydrochloric acid solution of pH 5 lithium nitrate. Subsequently, the reaction vessel made of fluororesin was kept at 45 ° C., and a hydrochloric acid solution of 102 g of semiconductor grade 50 wt% hydrofluoric acid and lithium nitrate was added at 200 g / L · Hr with a stirring speed of 0.5 m / sec. Simultaneous dripping was performed so that it might become a dripping speed. Further, stirring was performed for 8 hours.
次に、得られた沈殿物を吸引濾過により濾別した。回収した結晶を水で繰り返し洗浄し、その後、１０５℃で６時間乾燥した。得られた結晶の収量は４５．９ｇ（収率８７％）であった。 Next, the obtained precipitate was separated by suction filtration. The recovered crystals were washed repeatedly with water and then dried at 105 ° C. for 6 hours. The yield of the obtained crystal was 45.9 g (yield 87%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ、０．９１ｇ／ｃｍ３であった。また、安息角を測定したところ４４度であり、平均粒径は７５μｍであった。更に、１０５℃で６時間乾燥後のフッ化リチウム中の酸素濃度は２２０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.91 g / cm 3 . Further, the angle of repose was measured to be 44 degrees, and the average particle size was 75 μm. Furthermore, the oxygen concentration in lithium fluoride after drying at 105 ° C. for 6 hours was 220 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例５）
炭酸リチウム７４０ｇを４５重量％硝酸２８５０ｇに加えて攪拌溶解を行った後、０．４５μｍのメンブレンフィルターにてろ過を行い、不溶解成分を除去した。これにより、ｐＨ７の硝酸リチウム溶液を作製した。
(Example 5)
740 g of lithium carbonate was added to 2850 g of 45% by weight nitric acid and dissolved by stirring, followed by filtration with a 0.45 μm membrane filter to remove insoluble components. This produced a pH 7 lithium nitrate solution.
続いて、フッ素樹脂製反応槽を５０℃に保ち、一般グレードの２５重量％フッ酸４０００ｇと、前記硝酸リチウム溶液を、０．８ｍ／秒の攪拌速度で、全量に対し３００ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、６時間の攪拌を行った。 Subsequently, the fluororesin reaction vessel was kept at 50 ° C., and 4000 g of general grade 25 wt% hydrofluoric acid and the lithium nitrate solution were mixed at 300 g / L · Hr with a stirring speed of 0.8 m / sec. Simultaneous dropping was performed so as to obtain a dropping speed. Further, stirring was performed for 6 hours.
次に、得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行った。その結果、４７２ｇの結晶が得られた（収率９１％）。得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ、０．７７ｇ／ｃｍ３であった。また、安息角を測定したところ４８度であり、平均粒径は５０μｍであった。更に、１０５℃で７２時間乾燥後のフッ化リチウム中の酸素濃度は４９０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Next, the obtained crystal was subjected to solid-liquid separation, and the solid was repulped and dried. As a result, 472 g of crystals were obtained (yield 91%). When the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.77 g / cm 3 . The angle of repose was measured to be 48 degrees, and the average particle size was 50 μm. Furthermore, the oxygen concentration in lithium fluoride after drying at 105 ° C. for 72 hours was 490 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例６）
炭酸リチウム７４ｇを２３重量％硝酸１０６０ｇに加えて攪拌溶解を行った後、水酸化リチウムを加えて、ｐＨ１０．０の硝酸リチウム溶液を調整した。続いて、フッ素樹脂製反応槽を３０℃に保ち、半導体グレードの５０重量％フッ酸２００ｇと前記硝酸リチウム溶液を、１ｍ／秒の攪拌速度で、全量に対し１０ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、１２時間の攪拌を行った。
(Example 6)
After 74 g of lithium carbonate was added to 1060 g of 23 wt% nitric acid and dissolved by stirring, lithium hydroxide was added to prepare a pH 10.0 lithium nitrate solution. Subsequently, the reaction vessel made of fluororesin was kept at 30 ° C., and 200 g of semiconductor grade 50 wt% hydrofluoric acid and the lithium nitrate solution were added at a stirring rate of 1 m / sec and a dropping rate of 10 g / L · Hr with respect to the total amount. Then, simultaneous dripping was performed. Furthermore, stirring was performed for 12 hours.
次に、得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、５０．４ｇの結晶が得られた（収率９７％）。更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ、０．９２ｇ／ｃｍ３であった。また、安息角を測定したところ４１度であり、平均粒径は７５μｍであった。さらに、１０５℃６時間乾燥後のフッ化リチウム中の酸素濃度は２００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Next, the obtained crystals were subjected to solid-liquid separation, and the solid was washed with repulp and dried to obtain 50.4 g of crystals (yield 97%). Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.92 g / cm 3 . Further, the angle of repose was measured and found to be 41 degrees, and the average particle size was 75 μm. Furthermore, the oxygen concentration in lithium fluoride after drying at 105 ° C. for 6 hours was 200 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例７）
水酸化リチウム８４ｇを６９重量％硝酸２７４ｇに加え攪拌溶解を行い、ｐＨ５の硝酸リチウム溶液を作製した。続いて、フッ素樹脂製反応槽を１５℃に保ち、工業用グレードの２０重量％フッ酸２５０ｇと前記硝酸リチウム溶液を、１ｍ／秒の攪拌速度で全量に対し、１００ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、１．５時間の攪拌を行った。
(Example 7)
84 g of lithium hydroxide was added to 274 g of 69% by weight nitric acid and dissolved by stirring to prepare a pH 5 lithium nitrate solution. Subsequently, the reaction vessel made of fluororesin was kept at 15 ° C., and 250 g of industrial grade 20 wt% hydrofluoric acid and the lithium nitrate solution were added at a rate of 100 g / L · Hr with respect to the total amount at a stirring speed of 1 m / sec. Then, simultaneous dripping was performed. Further, stirring was performed for 1.5 hours.
次に、得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４３．２ｇの結晶が得られた（収率８３％）。 Next, the obtained crystals were subjected to solid-liquid separation, and the solid was washed with repulp and dried to obtain 43.2 g of crystals (yield 83%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．８１ｇ／ｃｍ３であった。さらに、安息角を測定したところ４３度であり、平均粒径は６０μｍであった。更に、１０５℃４時間乾燥後の得られたフッ化リチウム中の酸素濃度は３００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.81 g / cm 3 . Furthermore, when the angle of repose was measured, it was 43 degrees, and the average particle size was 60 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 4 hours was 300 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例８）
硝酸リチウム１４００ｇを純水４４２０ｇに加え攪拌溶解を行った後、０．４５μｍのメンブレンフィルターにてろ過を行い、不溶解成分を除去した。さらに、このろ液をＣＲ１１（キレート樹脂）にてイオン交換を行った。これにより、ｐＨ７の硝酸リチウム水溶液を作製した。
(Example 8)
After 1400 g of lithium nitrate was added to 4420 g of pure water and dissolved by stirring, it was filtered through a 0.45 μm membrane filter to remove insoluble components. Further, the filtrate was subjected to ion exchange with CR11 (chelate resin). As a result, a pH 7 lithium nitrate aqueous solution was prepared.
続いて、フッ素樹脂製反応槽を４５℃に保ち、半導体グレードの５０重量％フッ酸１４００ｇと前記硝酸リチウム水溶液を、２ｍ／秒の攪拌速度で、全量に対し２００ｇ／Ｌ・Ｈｒの滴下速度となるように同時滴下を行った。更に、８時間の攪拌を行った。 Subsequently, the reaction vessel made of fluororesin was kept at 45 ° C., and a dropping rate of 200 g / L · Hr with respect to the total amount of 1400 g of semiconductor grade 50 wt% hydrofluoric acid and the aqueous lithium nitrate solution was stirred at 2 m / sec. Simultaneous dripping was performed so that it might become. Further, stirring was performed for 8 hours.
次に、得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４８９ｇの結晶が得られた（収率９３％）。 Next, solid-liquid separation of the obtained crystal was performed, and the solid was washed with repulp and dried. As a result, 489 g of crystal was obtained (yield 93%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．９２ｇ／ｃｍ３であった。また、安息角を測定したところ、４０度であり、平均粒径は７５μｍであった。更に、１０５℃で９時間乾燥後のフッ化リチウム中の酸素濃度は２００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.92 g / cm 3 . The angle of repose was measured and found to be 40 degrees and the average particle size was 75 μm. Furthermore, the oxygen concentration in lithium fluoride after drying at 105 ° C. for 9 hours was 200 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例９）
炭酸リチウム７４ｇを３５重量％塩酸２１７ｇに加え攪拌溶解を行い、ｐＨ７の塩化リチウム溶液を作製した。続いて、フッ素樹脂製反応槽を氷浴で０℃に冷却しながら、半導体グレードの５０重量％フッ酸１５６ｇと前記塩化リチウム溶液を、２．５ｍ／秒の攪拌速度で、全量に対し１５０ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、３時間の攪拌を行った。
Example 9
74 g of lithium carbonate was added to 217 g of 35% by weight hydrochloric acid and dissolved by stirring to prepare a pH 7 lithium chloride solution. Subsequently, while cooling the fluororesin reaction tank to 0 ° C. with an ice bath, 156 g of a semiconductor grade 50 wt% hydrofluoric acid and the lithium chloride solution were added at a stirring speed of 2.5 m / sec to 150 g / Simultaneous dripping was performed so that the dripping speed of L · Hr was obtained. Further, stirring was performed for 3 hours.
次に、得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４７．０ｇの結晶が得られた（収率９０％）。得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ１．２５ｇ／ｃｍ３であった。また、安息角を測定したところ３４度であり、平均粒径は１００μｍであった。さらに、１０５℃１２時間乾燥後の得られたフッ化リチウム中の酸素濃度は８０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Next, solid-liquid separation of the obtained crystal was performed, and the solid was washed with repulp and dried. As a result, 47.0 g of crystal was obtained (yield 90%). When the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 1.25 g / cm 3 . Further, the angle of repose was measured and found to be 34 degrees, and the average particle size was 100 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 12 hours was 80 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例１０）
炭酸リチウム１０４ｋｇを３５重量％塩酸３１０ｋｇに加え攪拌溶解を行い、ｐＨ７の塩化リチウム溶液を作製した。続いて、フッ素樹脂でライニングした反応槽を１０℃に保ち、一般グレードの２５重量％フッ酸４００ｋｇと、調整した塩化リチウム溶液を２ｍ／秒の攪拌速度で、全量に対し２５０ｋｇ／ｍ３・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、５時間の攪拌を行った。
(Example 10)
104 kg of lithium carbonate was added to 310 kg of 35 wt% hydrochloric acid and dissolved by stirring to prepare a pH 7 lithium chloride solution. Subsequently, the reaction vessel lined with fluororesin was kept at 10 ° C., and 400 kg of a general grade 25 wt% hydrofluoric acid and the adjusted lithium chloride solution were stirred at a rate of 2 m / sec and 250 kg / m 3 · Hr with respect to the total amount. The dropwise addition was carried out so that the dropping speed was as follows. Further, stirring was performed for 5 hours.
得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、６９．０ｋｇの結晶が得られた（収率９４％）。得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．８９ｇ／ｃｍ３であった。さらに、安息角を測定したところ４１度であった。また、平均粒径は７０μｍであった。さらに、１２０℃５時間乾燥後の得られたフッ化リチウム中の酸素濃度は３１０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 The obtained crystals were subjected to solid-liquid separation, and the solid was washed with repulp and dried. As a result, 69.0 kg of crystals were obtained (yield 94%). When the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.89 g / cm 3 . Furthermore, the angle of repose was measured and found to be 41 degrees. The average particle size was 70 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 120 ° C. for 5 hours was 310 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（実施例１１）
塩化リチウム８５ｇを純水３２０ｇに加え攪拌溶解を行い、ｐＨ５の塩化リチウム溶液を作製した。続いて、フッ素樹脂製反応槽を２０℃に保ち、工業用グレードの１０重量％フッ酸５００ｇと前記塩化リチウム溶液を、１ｍ／秒の攪拌速度で、全量に対し１８０ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、１．５時間の攪拌を行った。
(Example 11)
85 g of lithium chloride was added to 320 g of pure water and dissolved by stirring to prepare a pH 5 lithium chloride solution. Subsequently, the fluororesin reaction vessel was kept at 20 ° C., and 500 g of industrial grade 10 wt% hydrofluoric acid and the lithium chloride solution were added at a rate of 180 g / L · Hr with a stirring speed of 1 m / sec. Then, simultaneous dripping was performed. Further, stirring was performed for 1.5 hours.
得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４５．５ｇの結晶が得られた（収率８８％）。 When the obtained crystals were subjected to solid-liquid separation, the solid was washed with repulp and dried, 45.5 g of crystals were obtained (yield 88%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ１．０２ｇ／ｃｍ３であった。さらに、安息角を測定したところ、３７度であった。また、平均粒径は８０μｍであった。さらに１５０℃３時間乾燥後の得られたフッ化リチウム中の酸素濃度は１６０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 1.02 g / cm 3 . Furthermore, when the angle of repose was measured, it was 37 degrees. The average particle size was 80 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 150 ° C. for 3 hours was 160 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
さらに、固液分離を行った際の濾液を１２５℃で蒸留を行い、塔頂から得られた蒸気留分を―１０℃で冷却した。この溶液の組成分析を行った。その結果、ＨＦ濃度：３重量％、ＨＣｌ濃度：１７重量％のフツ塩酸を回収できたことが確認された。 Further, the filtrate obtained when the solid-liquid separation was performed was distilled at 125 ° C., and the vapor fraction obtained from the top of the column was cooled at −10 ° C. The composition of this solution was analyzed. As a result, it was confirmed that hydrofluoric acid having an HF concentration of 3% by weight and an HCl concentration of 17% by weight could be recovered.
（実施例１２）
炭酸リチウム７４０ｇを３５重量％塩酸２３００ｇに加え攪拌溶解を行い、ｐＨ６の塩化リチウム溶液を作製した。続いてフッ素樹脂製反応槽を氷浴で０℃に冷却しながら、半導体グレードの５０重量％フッ酸２０００ｇと前記塩化リチウム溶液を、２ｍ／秒の攪拌速度で、全量に対し３００ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、６時間の攪拌を行った。
(Example 12)
740 g of lithium carbonate was added to 2300 g of 35% by weight hydrochloric acid and dissolved by stirring to prepare a pH 6 lithium chloride solution. Subsequently, while cooling the fluororesin reaction tank to 0 ° C. with an ice bath, 2000 g of semiconductor grade 50 wt% hydrofluoric acid and the lithium chloride solution were mixed at 300 g / L · Hr with a stirring speed of 2 m / sec. The dropwise addition was carried out so that the dropping speed was as follows. Further, stirring was performed for 6 hours.
得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４９４ｇの結晶が得られた（収率９５％）。 The obtained crystals were subjected to solid-liquid separation, and the solid was washed with repulp and dried to obtain 494 g of crystals (yield 95%).
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．８９ｇ／ｃｍ３であった。さらに、安息角を測定したところ、４２度であった。また、平均粒径は７０μｍであった。さらに１０５℃４８時間乾燥後の得られたフッ化リチウム中の酸素濃度は２５０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.89 g / cm 3 . Furthermore, the angle of repose was measured and found to be 42 degrees. The average particle size was 70 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 48 hours was 250 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
さらに、固液分離を行った際の濾液を１２５℃で蒸留を行い、塔頂から得られた蒸気留分を―５℃で冷却した。この溶液の組成分析を行った。その結果、ＨＦ濃度：２重量％、ＨＣｌ濃度：２０重量％のフツ塩酸を回収できたことが確認された。 Further, the filtrate obtained when the solid-liquid separation was performed was distilled at 125 ° C., and the vapor fraction obtained from the top of the column was cooled at −5 ° C. The composition of this solution was analyzed. As a result, it was confirmed that hydrofluoric acid having an HF concentration of 2% by weight and an HCl concentration of 20% by weight could be recovered.
（実施例１３）
硫酸リチウム２２０ｇを純水４０１ｇに加え、攪拌溶解を行い、ｐＨ７の硫酸リチウム水溶液を作製した。続いてフッ素樹脂製反応槽を２０℃に保ち、半導体グレードの５０重量％フッ酸２４０ｇと前記硫酸リチウム水溶液を１．５ｍ／秒の攪拌速度で、全量に対し５０ｇ／Ｌ・Ｈｒの滴下速度となるようにして同時滴下を行った。更に、６時間の攪拌を行った。
(Example 13)
220 g of lithium sulfate was added to 401 g of pure water and dissolved by stirring to prepare a pH 7 lithium sulfate aqueous solution. Subsequently, the reaction vessel made of fluororesin was kept at 20 ° C., and 240 g of semiconductor grade 50 wt% hydrofluoric acid and the lithium sulfate aqueous solution were stirred at a rate of 1.5 m / sec. Then, simultaneous dripping was performed. Further, stirring was performed for 6 hours.
得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４５．３ｇの結晶が得られた（収率８７％）。更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ１．１７ｇ／ｃｍ３であった。また、安息角を測定したところ３７度であり、平均粒径は８５μｍであった。さらに１０５℃３６時間乾燥後の得られたフッ化リチウム中の酸素濃度は１００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 When the obtained crystals were subjected to solid-liquid separation, the solid was washed with repulp and dried, 45.3 g of crystals were obtained (yield 87%). Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 1.17 g / cm 3 . Further, the angle of repose was measured and found to be 37 degrees, and the average particle size was 85 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 36 hours was 100 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（比較例１）
フッ素樹脂製反応槽を氷浴で０℃に冷却しながら、炭酸リチウム７４ｇを攪拌下、（水溶性のリチウム塩にせず直接）半導体グレードの５０重量％フッ酸８２．４ｇ中へ、２ｍ／秒の攪拌速度で、２００ｇ／Ｌ・Ｈｒの滴下速度となるように加えた。その後、３時間の攪拌を行った。
(Comparative Example 1)
While cooling the fluororesin reaction vessel to 0 ° C. with an ice bath, 74 g of lithium carbonate was stirred (directly without using a water-soluble lithium salt) into 82.4 g of semiconductor-grade 50 wt% hydrofluoric acid at 2 m / sec. The stirring speed was 200 g / L · Hr. Thereafter, stirring was performed for 3 hours.
次に、得られた沈殿物を吸引濾過により濾別し、回収した結晶を水にて繰り返し洗浄を行った後、１０５℃で６時間乾燥した。得られた結晶の収量は４９．３ｇ（収率９５％）であった。更に、ＸＲＤにより解析を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．３５ｇ／ｃｍ３であった。また、安息角を測定したところ６５度であり、平均粒径は１０μｍであった。さらに、１０５℃１２時間乾燥後の得られたフッ化リチウム中の酸素濃度は１５００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Next, the obtained precipitate was separated by suction filtration, and the recovered crystals were repeatedly washed with water and then dried at 105 ° C. for 6 hours. The yield of the obtained crystal was 49.3 g (yield 95%). Furthermore, when it analyzed by XRD, it turned out that it is LiF. Therefore, when the bulk density of this LiF was measured, it was 0.35 g / cm 3 . Further, the angle of repose was measured and found to be 65 degrees, and the average particle size was 10 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 12 hours was 1500 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（比較例２）
本比較例に於いては、特開２００１−１０６５２４号公報に記載の方法によりフッ化リチウムの製造を行った。即ち、水酸化リチウム７．６６ｇを超純水１０００ｇに溶解し、５０重量％濃度の半導体用フッ酸溶液２６ｍｌを加え、スターラで８時間の攪拌を行った。攪拌後に生成したリチウム沈殿物を、濾過・洗浄した。その後、室温で脱水・乾燥し、フッ素ガスを用いて６０℃で乾燥処理を行った。さらに、ＬｉＦ・ＨＦ中のＨＦ分を脱離させるため、１９０℃で６時間の乾燥を行った。得られた結晶の収量は３．８ｇであった。
(Comparative Example 2)
In this comparative example, lithium fluoride was produced by the method described in JP-A No. 2001-106524. That is, 7.66 g of lithium hydroxide was dissolved in 1000 g of ultrapure water, 26 ml of a 50 wt% concentration of hydrofluoric acid solution for semiconductor was added, and the mixture was stirred with a stirrer for 8 hours. The lithium precipitate formed after stirring was filtered and washed. Then, it dehydrated and dried at room temperature, and performed the drying process at 60 degreeC using the fluorine gas. Furthermore, in order to desorb the HF content in LiF · HF, drying was performed at 190 ° C. for 6 hours. The yield of the obtained crystal was 3.8 g.
更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．２１ｇ／ｃｍ３であった。また、安息角を測定したところ８０度であり、平均粒径は１０μｍであった。さらに１９０℃乾燥後の粉末中の酸素濃度は１８００重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.21 g / cm 3 . Further, the angle of repose was measured and found to be 80 degrees, and the average particle size was 10 μm. Furthermore, the oxygen concentration in the powder after drying at 190 ° C. was 1800 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
（比較例３）
炭酸リチウム７４ｇを６９重量％硝酸４５０ｇ中に加え攪拌溶解を行い、硝酸リチウム溶液を作製した。続いて、フッ素樹脂製反応槽中に半導体グレードの５０重量％フッ酸１５６ｇを加え２０℃に保ちながら、前記硝酸リチウム溶液を２ｍ／秒の攪拌速度で２００ｇ／Ｌ・Ｈｒの滴下速度となるようにして滴下を行った。更に、４５℃で１２時間の攪拌を行った。
(Comparative Example 3)
74 g of lithium carbonate was added to 450 g of 69 wt% nitric acid and dissolved by stirring to prepare a lithium nitrate solution. Subsequently, 156 g of semiconductor grade 50 wt% hydrofluoric acid was added to the reaction vessel made of fluororesin and maintained at 20 ° C., so that the lithium nitrate solution was dropped at a rate of 200 g / L · Hr at a stirring speed of 2 m / sec. Then, dropping was performed. Furthermore, stirring was performed at 45 ° C. for 12 hours.
得られた結晶の固液分離を行い、固体をリパルプ洗浄し、乾燥を行ったところ、４７．１ｇの結晶が得られた（収率９１％）。更に、得られた結晶のＸＲＤ測定を行ったところ、ＬｉＦであることが分かった。そこで、このＬｉＦの嵩密度を測定したところ０．５９ｇ／ｃｍ３であった。さらに、安息角を測定したところ、５６度であった。また、平均粒径は２０μｍであった。さらに１０５℃８時間乾燥後の得られたフッ化リチウム中の酸素濃度は１３５０重量ｐｐｍであった。尚、嵩密度、安息角、平均粒径、酸素濃度の測定方法は、前記実施例１と同様とした。 When the obtained crystals were subjected to solid-liquid separation, the solid was washed with repulp and dried, 47.1 g of crystals were obtained (yield 91%). Furthermore, when the XRD measurement of the obtained crystal was performed, it was found to be LiF. Therefore, when the bulk density of this LiF was measured, it was 0.59 g / cm 3 . Furthermore, when the angle of repose was measured, it was 56 degrees. The average particle size was 20 μm. Furthermore, the oxygen concentration in the obtained lithium fluoride after drying at 105 ° C. for 8 hours was 1350 ppm by weight. The bulk density, angle of repose, average particle diameter, and oxygen concentration were measured in the same manner as in Example 1.
Claims (4)
前記リチウム塩溶液に対し、１０重量％以上６０重量％以下のフッ酸を１〜５モル当量の割合で、リチウム塩溶液及びフッ酸を反応器に同時滴下しながら反応させ、安息角が５０度以下、且つ、嵩密度が０．７５ｇ／ｃｍ３以上のフッ化リチウムを作製するフッ化リチウムの製造方法。 Producing a lithium salt solution in which the concentration of at least one lithium compound selected from the group consisting of lithium carbonate, lithium hydroxide, lithium nitrate, lithium chloride, and lithium sulfate is 10 to 50% by weight;
With respect to the lithium salt solution, 10 to 60% by weight of hydrofluoric acid is reacted at a ratio of 1 to 5 molar equivalents while simultaneously dropping the lithium salt solution and hydrofluoric acid into the reactor, and the angle of repose is 50 degrees. Hereinafter, a method for producing lithium fluoride, which produces lithium fluoride having a bulk density of 0.75 g / cm 3 or more.
Method for producing a lithium fluoride according to any one of claims 1 to 3, wherein to Rukoto the oxygen content of lithium fluoride below 1000 ppm by weight by drying.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006349822A JP5122809B2 (en) | 2006-12-26 | 2006-12-26 | Method for producing lithium fluoride |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006349822A JP5122809B2 (en) | 2006-12-26 | 2006-12-26 | Method for producing lithium fluoride |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2008156190A JP2008156190A (en) | 2008-07-10 |
| JP5122809B2 true JP5122809B2 (en) | 2013-01-16 |
Family
ID=39657542
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006349822A Expired - Fee Related JP5122809B2 (en) | 2006-12-26 | 2006-12-26 | Method for producing lithium fluoride |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5122809B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110182830A (en) * | 2019-07-06 | 2019-08-30 | 贵州理工学院 | A method of preparing high-purity fluorination reason |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4591557B2 (en) | 2008-06-16 | 2010-12-01 | ソニー株式会社 | Audio signal processing apparatus, audio signal processing method, and audio signal processing program |
| IN2014DN01632A (en) * | 2011-08-12 | 2015-05-15 | Rhodia Operations | |
| ES2766777T3 (en) | 2012-05-25 | 2020-06-15 | Lanxess Deutschland Gmbh | Preparation of high purity lithium fluoride |
| CN111606336A (en) * | 2020-05-19 | 2020-09-01 | 百杰瑞(荆门)新材料有限公司 | Preparation method of lithium fluoride |
| CN113955774B (en) * | 2020-09-24 | 2022-11-22 | 中国科学院上海有机化学研究所 | Nuclear-purity-grade lithium fluoride-7 as well as preparation method and application thereof |
| CN113697829A (en) * | 2021-09-07 | 2021-11-26 | 江苏容汇通用锂业股份有限公司 | Preparation method of lithium fluoride |
| CN114920271B (en) * | 2022-05-26 | 2023-03-03 | 福建省龙德新能源有限公司 | Method for preparing lithium hexafluorophosphate by dry method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0742103B2 (en) * | 1986-09-16 | 1995-05-10 | 日本電信電話株式会社 | Method for producing alkali metal fluoride |
| JP2772302B2 (en) * | 1991-06-24 | 1998-07-02 | 日本電信電話株式会社 | Method for producing high-purity metal fluoride |
| DE19809420A1 (en) * | 1998-03-05 | 1999-09-09 | Basf Ag | Process for the production of high-purity lithium salts |
| JP2001106524A (en) * | 1999-10-08 | 2001-04-17 | Nippon Telegr & Teleph Corp <Ntt> | Producing method of alkaline fluoride |
-
2006
- 2006-12-26 JP JP2006349822A patent/JP5122809B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110182830A (en) * | 2019-07-06 | 2019-08-30 | 贵州理工学院 | A method of preparing high-purity fluorination reason |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2008156190A (en) | 2008-07-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5122809B2 (en) | Method for producing lithium fluoride | |
| JP5690365B2 (en) | Method for producing lithium sulfide powder | |
| CN111466051B (en) | Battery recycling by treating leach liquor with metallic nickel | |
| US8609056B2 (en) | Iron(III) orthophosphate for Li ion accumulators | |
| JP5794028B2 (en) | Method for producing lithium tetrafluoroborate solution | |
| JP5414143B2 (en) | Method for producing sulfide solid electrolyte | |
| JP4810867B2 (en) | Method for producing electrolyte for lithium ion battery | |
| CN106882819B (en) | A kind of lithium hexafluoro phosphate prepares purification process | |
| JP4968945B2 (en) | Composite carbonate and method for producing the same | |
| CN108423651B (en) | Method for preparing lithium difluorophosphate | |
| KR20200049164A (en) | Very efficient Method for preparing lithium bis(fluorosulfonyl)imide | |
| KR101955096B1 (en) | Novel preparing method of very efficient and simple lithium bis(fluorosulfonyl)imide | |
| JP6826447B2 (en) | Method for reducing the amount of residual lithium in the positive electrode active material particles | |
| JPH09165210A (en) | Production of lithium hexafluorophosphate | |
| CN110683564B (en) | Lithium hexafluorophosphate-containing mixture crystal and application thereof | |
| JP4833539B2 (en) | Lithium sulfide particle powder, method for producing the same, and inorganic solid electrolyte | |
| CN113646261A (en) | Aqueous solution of alkali metal salt of bis (fluorosulfonyl) imide, container containing the aqueous solution, and method for storing or transporting the aqueous solution | |
| KR20140102248A (en) | Lipf6 solutions | |
| CN116040592A (en) | Preparation method of lithium bis (fluorosulfonyl) imide | |
| AU2020401568B2 (en) | Process and method for refining lithium carbonate starting from an impure lithium chloride solution | |
| CN110690503B (en) | High-stability fluorine-containing electrolyte and lithium ion battery | |
| JP2007184246A (en) | Method of manufacturing electrolyte solution for lithium ion battery and lithium ion battery using it | |
| JP2012232888A (en) | Method for producing lithium fluorosulfonate, and lithium fluorosulfonate | |
| JP3483120B2 (en) | Method for producing electrolyte for lithium battery | |
| JP2009215138A (en) | Method of purification of metal fluoride |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20091002 |
|
| RD03 | Notification of appointment of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7423 Effective date: 20091002 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20111227 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20120802 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20120905 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20121019 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20121025 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20151102 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |