JP2004002181A - Conductive vanadate glass and manufacture method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive vanadate glass that is applicable under high corrosive circumstance such as acids, alkalis and the like while maintaining electroconductivity and chemical durability (corrosion resistance) with good balance and that is capable of precisely performing a design by suppressing the variation of properties due to its ingredient contnet and its composition and is capable of effectively recycling industrial wastes such as glassware, for example, glass bottles for drinks, and coal ash. <P>SOLUTION: The conductive vanadate glass comprises a glass composition comprising 0.1-25 mol % of vanadium oxide, of which the electroconductivity at room temperature is 10<SP>-8</SP>-10<SP>-4</SP>S/cm and the amount of elution after the immersion in 20% hydrochloric acid for 72 hours is 35% by mass or less. <P>COPYRIGHT: (C)2004,JPO

Description

【００２４】
【表２】

【００２５】
以上のように作成されたガラス組成物の各試料について示差熱分析（ＤＴＡ）や示差走査熱量測定（ＤＳＣ）などを行うことによりそれぞれのガラス転移温度（Ｔｇ）と溶融温度を求めた。それらを表３に示す。なおＤＴＡ測定における昇温速度は毎分１５℃に設定した。
【００２６】
【表３】

【００２７】
ガラスをそのガラス転移温度以上の温度で加熱すると、ガラス骨格の切断やガラスを構築する骨格の再構築、フラグメントの再配列が起きる。しかし、ガラスを長時間、ガラス転移温度以上の温度で加熱すると、ガラス相中に結晶相が析出し、それらが成長することにより、ガラスは結晶化ガラス（ガラスセラミック）となって、電気伝導度や光透過性等を低下させる要因となる。従って、アニーリング処理温度における保持時間は、そのガラス処理量や加熱装置の熱容量等によっても変動するが、所定の電気伝導度を保持させることができ、しかもこのような結晶化が起こらないような範囲、例えば１０分〜１８０分間、好ましくは２０〜６０分間の範囲に設定しておくことが望ましい。
熱処理温度はガラス転移温度以上、結晶化温度以下（示差熱分析における結晶化発熱ピークの裾の高温側端点温度又は発熱ピークの中心点における温度）の範囲に設定する。この熱処理時間が短時間であれば、結晶相が析出する前に（結晶化ガラスとなる前に）ガラス骨格のゆがみ（ひずみ）を小さくして、いわゆる構造緩和を起こさせることができ、電気伝導度を所定の範囲のレベルにまで高められた導電性バナジン酸塩ガラスを作製できる。
【００２８】
前記アニーリング等の熱処理がなされたガラス組成物の試料の電気伝導度を以下のようにして測定した。
なお、測定に際してはガラス組成物の試料厚さが１ミリメートル以下のガラス片を用いて、直流二端子法または直流四端子法、交流四端子法を適用して室温で値を求めた。なお、この測定においては、溶融した金属インジウムまたは金属銀ペーストを用いて、ガラス表面にリード線を固定させたものを電極とした。
【００２９】
各試料の化学耐久性は、３０℃の設定温度に保持された恒温槽に、所定濃度の塩酸及び水酸化ナトリウム溶液を入れた密閉容器を載置し、この腐食性の溶液中に予め秤量した試料を浸漬させ、所定時間後に取り出された試料を秤量して、その減量から溶出量を求めた。本実施の形態では化学耐久性の指標として、▲１▼２０％塩酸中７２時間浸漬後の溶出量、▲２▼２０％塩酸中２４０時間後の溶出量、▲３▼１モル水酸化ナトリウム溶液中７２時間浸漬後の溶出量、▲４▼１モル水酸化ナトリウム溶液中２４０時間浸漬後の溶出量をそれぞれ測定した。
表３に、以上のようにして求められた各試料の電気伝導性と化学耐久性等のデータを示している。
以下、表１〜表３を参照しながら実施例１〜２０及びその比較例１〜４について説明する。
【００３０】
（実施例１〜９）
表１に示すように実施例１〜９は、バナジン酸塩組成物の配合量を１０質量％に固定し、ガラスびんの配合量を９０〜４０質量％の範囲で変化させて不足分を酸化ナトリウムや酸化カリウム、酸化カルシウム等で補うように配合して得られたものである。
なお、実施例５を除く実施例１〜９のデータはこの所定比率で配合された混合物を１０００℃で１時間保持して溶融させた後、ガラス化したものであり、実施例５は１２００℃で１時間保持して溶融させたもののデータを示している。
表３に示されるように実施例２〜６ではガラス転移温度が５２１℃以下になるように炭酸ナトリウムを加えて、原料中の酸化ナトリウムの量を調整した。このとき、炭酸ナトリウムは（Ｎａ_２ＣＯ_３→Ｎａ_２Ｏ＋ＣＯ_２↑）の反応により、ガラス中では、Ｎａ_２Ｏとなる。（ここで、Ｎａ_２Ｏ分子は単独で存在する訳ではなく、≡Ｓｉ−Ｏ⁻・・・Ｎａ^＋のイオン結合を構築し、網目修飾イオンの役割を果たしている。）
表２のデータに示されるように、原料組成を調整してガラス中の酸化カルシウムや酸化ナトリウムの含有量などを所定範囲にして、ガラス中の各イオンの配置を決定して、所定の化学耐久性と電気伝導性とを兼ね備えたガラス組成物とすることができる。
【００３１】
表３の化学耐久性のデータに示すように実施例１（ガラスびん：９０質量％・バナジン酸塩組成物：１０質量％を原料とした導電性バナジン酸塩ガラス）の化学耐久性は極めて高いことが分かる。また、実施例２（ガラスびん：８５質量％・バナジン酸塩組成物：１０質量％・酸化ナトリウム：５質量％）及び実施例３（ガラスびん：８０質量％・バナジン酸塩組成物：１０質量％・酸化ナトリウム：１０質量％）の化学耐久性にも実用上全く問題ないことが分かった。
実施例４（ガラスびん：７５質量％・バナジン酸塩組成物：１０質量％・酸化ナトリウム：１５質量％）の化学耐久性は実施例１〜３のものに比較してそれほど良くないが、酸濃度などがさほど高くなければ十分使用に耐えられることが分かる。
実施例５は酸化ホウ素をガラス化調整成分として５質量％添加した例を示すものであり、その電気伝導度が１．１×１０^−７Ｓ・ｃｍ^−１と実施例中では低いが、ヒータ用などとしての通電加熱性を有しており、酸化ホウ素の添加により熱膨張率、耐熱性、および化学耐久性の高い導電性バナジン酸塩ガラスが得られることがわかる。
【００３２】
実施例６は（ガラスびん：４０質量％・バナジン酸塩組成物：１０質量％・酸化ナトリウム：１０質量％・酸化ケイ素：４０質量％）として、ガラスびんの配合量を比較的少なくしその不足分を酸化ケイ素で補うようにした実験例を示しており、この電気伝導度は１５×１０^−７Ｓ・ｃｍ^−１と発熱体等として使用できる範囲内であり、その化学耐久性は高く、２０％ＨＣｌ中で７２時間後の溶出量が０．０３質量％とごく少ないことが分かる。
実施例７〜９はガラスびん：８０質量％、バナジン酸塩組成物：１０質量％をベースとして、これにそれぞれ▲１▼酸化カリウム１０質量％、▲２▼酸化カルシウム１０質量％、▲３▼酸化カリウム５質量％と酸化カルシウム５質量％の混合物を配合したものである。この実施例７〜９における２０％ＨＣｌ中で７２時間後の溶出量はそれぞれ、▲１▼０．０８質量％、▲２▼０．１０質量％、▲３▼０．０９質量％となり、化学耐久性が良好であり、腐食性雰囲気に晒されるような電気デバイス用として使用できることが分かる。
【００３３】
比較例１はバナジン酸塩組成物の配合量を８０質量％に増大させ、これにガラスびん１０質量％と酸化ナトリウム１０質量％を配合したもので、この場合には、電気伝導性を所定レベルに維持できるものの、２０％ＨＣｌ中で７２時間後の溶出量が１００質量％と大きくなり、化学耐久性が低下し、化学耐久性を所定範囲に維持させるためには表３に示すように酸化バナジウムの配合量に上限値が存在することを示唆している。なお、この電気伝導度は当初１６×１０^−７Ｓ・ｃｍ^−１であったが、これにさらに所定の熱処理を付加することにより電気伝導度の値を調整できることがわかった。
すなわち、この試料を空気中で３７０℃で３０分間アニーリングしたところ、その電気伝導度は２４×１０^−７Ｓ・ｃｍ^−１に増加し、１時間熱処理したもので２５×１０^−７Ｓ・ｃｍ^−１、２時間熱処理後では１４×１０^−７Ｓ・ｃｍ^−１に低下した。このように熱処理時間や熱処理温度にもそれぞれ適正範囲があり、この設定条件を適正に定めることで所要の化学耐久性と電気伝導性を有した導電性バナジン酸塩ガラスを製造することができる。
【００３４】
比較例２はガラスびん：７０質量％とバナジン酸塩組成物：３０質量％の例である。この場合には酸化バナジウム等の配合比率が適正でないために、化学耐久性の指標となる２０％濃度の塩酸中の７２時間浸漬後の溶出量が４０．７質量％と実用上使用できる限界以上に高くなっていることが分かる。
【００３５】
以上説明したように、表３の電気伝導性（電気伝導度σ）のデータから実施１〜９のいずれの系においても、１０^−５〜１０^−７Ｓ・ｃｍ^−１の範囲の比較的高い電気伝導度を示しており、前記化学耐久性に加えて優れた電気伝導性のガラス材料として適用できることが分かった。
このようにガラスびんとバナジン酸塩組成物とを組み合わせた導電性バナジン酸塩ガラスは化学耐久性に極めて優れており、ガラス転移温度などの設計、制御も容易である。従って、この電気伝導性と化学耐久性とを利用して医薬品製造に用いられる反応容器等において、その静電気を逃がすための静電気防止材などにも活用できる他、温排水管などへの貝殻の付着防止材としても活用できる。
【００３６】
なお、このような場合の導電性バナジン酸塩ガラスの成膜方法としては、真空蒸着法やスパッタリング法、イオンプレーティング法等のほかに溶融したガラスを基板上に吹きつけて固化させたりする等の方法を適用することができる。
また、この導電性バナジン酸塩ガラスの適度の電気伝導性を利用して通電加熱することにより、ビルや車等の窓ガラスのヒータとして用いることができ、くもり止めや結露防止などにも効果があると予想される。なお、原料となるガラスびんとして、本実施例ではコカコーラボトラーズ社の清涼飲料水用ガラスびんを用いたが、これに限らず、他のガラスびんでも同等あるいはそれ以上の成果が期待できる。
【００３７】
（実施例１０〜１５）
実施例１０〜１５及び比較例３はバナジン酸塩組成物１０質量％（または３０質量％）をベースとして、これに石炭灰や酸化ナトリウム、酸化カリウム、酸化カルシウム等のガラス化調整成分を配合した場合の実験例を示している。
実施例１０は、石炭灰：９０質量％、バナジン酸塩組成物：１０質量％の混合系を、実施例１５は、石炭灰：７０質量％、バナジン酸塩組成物：３０質量％の混合系であり、実施例１１〜１４は石炭灰及びバナジン酸塩組成物に加えて、ガラス化調整成分を配合した系列のものを示している。
これに対して、比較例３では石炭灰：７５質量％、バナジン酸塩組成物：１０質量％、酸化ナトリウム：１５質量％の配合比率や熱処理条件等が適正でない混合系のデータを示している。
実施例１０〜１５のように石炭灰を用いたガラス系、特に実施例１０（石炭灰：９０質量％、バナジン酸塩組成物：１０質量％のガラス）は塩酸のみならず水酸化ナトリウム溶液中においても高い化学耐久性を示していることがわかる。
また、アルカリ成分等を添加した実施例１１（石炭灰：８０質量％、バナジン酸塩組成物：１０質量％、酸化ナトリウム：１０質量％）ではその化学耐久性にも大きな問題はないが、比較例３のようにアルカリ成分（酸化ナトリウム）が１５質量％以上になると２０％塩酸中での溶出量が増加している。
このように各原料構成によって化学耐久性が変化して、比較例３では酸化ナトリウムが規定量を越えるために大幅に化学耐久性が劣化しているのが分かる。
このように火力発電所等から排出される石炭灰等の廃棄物を、バナジン酸塩組成物に添加し、カルシウムやケイ素、アルミニウム等の原料として適用できる。さらに、導電性バナジン酸塩ガラスを安価な廃棄物原料を用いて製造でき、経済性や環境保護性にも優れていることが明らかになった。
【００３８】
（実施例１６〜２０）
実施例１６〜２０は、バナジン酸塩組成物に医薬品製造用反応容器（鉄製）の表面保護材として用いられるケイ酸塩ガラスを原料の一部として配合して導電性バナジン酸塩ガラスを作製した実験例である。
実施例１６〜２０の導電性バナジン酸塩ガラスは、所定粒度に粉砕されたケイ酸塩ガラスに対してバナジン酸塩組成物（ＢａＯ：１５モル％、Ｖ_２Ｏ_５：７０モル％、Ｆｅ_２Ｏ_３：１５モル％）または酸化バナジウムをそれぞれ一定の質量比で混合したものを１４００℃で１時間溶融することにより作成した。この試料の化学耐久性と電気伝導性を評価した測定結果を表３に示す。なお、比較例４としてケイ酸ガラスのみの場合のデータを示している。
【００３９】
表３から分かるように、実施例１６〜１９の導電性バナジン酸塩ガラスは実施例１〜１５や比較例４のものに比べて化学耐久性に大きな違いは見られず、化学反応容器用の防護被膜材として実用上使用できるレベルのものであることがわかる。
実施例１８（ケイ酸塩ガラス：８０質量％、バナジン酸塩組成物：２０質量％）では、２０％ＨＣｌ中で７２時間の溶出量が４．３５質量％となり、化学耐久性が若干落ちているように見えるが、試験に用いた塩酸濃度が高濃度であることを考えると、多くの場合ほとんど問題なく使用できるレベルのものである。
また、実施例１６〜２０は全実施例の中でも比較的高い電気伝導度を示しており、ガラス半導体として幅広い分野での利用が期待できる。
なお、実施例１９（ケイ酸塩ガラス：９０質量％、酸化バナジウム：１０質量％）と実施例２０（ケイ酸塩ガラス：８０質量％、酸化バナジウム：２０質量％）の系は、バナジン酸塩組成物を用いる系（実施例１６〜１８）との比較のために作成したものであり、これらのデータの比較から、バナジン酸塩組成物を必ずしも出発原料としなくとも、該当する試薬等を添加してその全体の化学組成を所定範囲に調整したり、熱処理条件を適切に設定したりすることなどにより所定の化学耐久性と電気伝導性を有した導電性バナジン酸塩ガラスが作製できることを示している。
酸化バナジウムを２０質量％とした実施例２０では、その化学耐久性の指標である２０％ＨＣｌ中での溶出量が２９．６質量％と他の系統の実施例に比べて増加しているが、腐食性が比較的低い雰囲気下で用いられる電気デバイス用としては十分適用できるレベルのものであった。
【００４０】
本実施例１〜２０におけるガラス転移温度は表３に示すように、４８４℃（実施例４）〜６７０℃（実施例１０）の範囲であり、その軟化温度は５７４℃（実施例４）〜８１９℃（実施例１１）の範囲である。これらのデータから導電性バナジン酸塩ガラスを反応容器のライニング材として適用する際の溶けたガラスの流動性などを良好な範囲に確保でき、施工性に優れること等がわかる。
このように医薬品製造用反応容器表面に使われているケイ酸塩ガラスとバナジン酸塩組成物または酸化バナジウムを所定比率で組み合わせて作成した導電性バナジン酸塩ガラスは化学耐久性に優れていると共に、ガラス転移温度などの設計、制御も容易である。さらに、比較例４に示したケイ酸塩ガラスに比較して１０万倍（×１０^５）以上となる電気伝導度（１０^−７〜１０^−４Ｓ・ｃｍ^−１）を有するため、通電加熱用の発熱体として有効に使用できる他、医薬品製造用反応容器の静電気防止材として反応操作時における安全性を高めることができる。また温排水管の貝殻付着防止などにも活用できる他、その適度の導電性により電熱ヒータとしてビルや車などのガラスのくもり止めや結露防止などにも適用できる。
【００４１】
本発明の実施の形態の導電性バナジン酸塩ガラス及びその製造方法は以上のように構成されているので以下の作用を有する。
（１）電気伝導性と化学耐久性とに優れたガラス骨格を形成させることができ、腐食環境下で用いられる化学反応容器用の導電性を有した防護被膜材や、電極材料、固体電解質、サーミスタ等のセンサとしての化学耐久性を保持させることができる。
（２）ガラスビンや火力発電所等から排出される石炭灰等の廃棄物を、導電性バナジン酸塩ガラスのケイ素、カルシウム、ナトリウムなどの原料として適用でき、資源の有効活用が図れると共に、廃棄物量を削減して環境保護性にも優れている。
（３）ガラス骨格を所定条件に制御して形成でき、電子ホッピング効果による電気伝導性の向上、ガラス表面の化学ポテンシャルの制御による化学耐久性の向上、溶融温度、ガラス転移温度を制御した生産性の向上などの利点がある。
（４）ガラス質としているため、層状構造を有した結晶質のものに比べて層間化合物の生成などのインターカレーションによる構造変化を少なくでき、安定した性能を維持できる。
（５）結晶質のものに比べて薄膜化が容易であり、複雑な形状等への被膜形成等が容易で加工性にも優れており、種々の形態の半導体素子や反応容器の被膜形成材としての応用が可能である。
（６）電気伝導性及び化学耐久性を調整するのに有効なバナジウム、ケイ素、鉄、カルシウム、ナトリウムなどが所定量含まれているので、化学耐久性と電気伝導性の両者をバランスさせた適正状態に維持させることができる。
（７）導電性バナジン酸塩ガラスを安価な廃棄物原料を用いて製造できるので、経済性に優れている。
（８）熱処理温度や保持時間等の熱処理条件と、この熱処理条件により得られる導電性バナジン酸塩ガラスの電気伝導性や化学耐久性との対応関係を用いて、熱処理条件を選択して、その特性を任意に調整することができるので、用途や使用環境に応じた特性を有した電気伝導性の素材を製造できる。
【００４２】
【発明の効果】
請求項１に記載の導電性バナジン酸塩ガラスによれば、以下の効果を有する。
（１）酸化バナジウムを所定量含むガラス組成物としているので、電気伝導性と化学耐久性とに優れたガラス骨格を形成させることができ、その電気伝導性を有効に利用して、腐食環境下で用いられる化学反応容器用のライニング等の防護被膜材や、電極材料、固体電解質、サーミスタ等のセンサとしての化学耐久性を保持させることができる。
（２）電気伝導性及び化学耐久性が所定範囲に設定されるので、酸やアルカリに晒される反応容器等の保護被膜やサーミスタ、電極素子に適用する場合の設計を容易にでき、設計の自在性に優れている。
（３）ガラス組成物にはバナジウムの他にバリウムや鉄、カルシウム、ナトリウム等を含ませることができるので、ガラス骨格を所定条件に制御して形成でき、▲１▼イオン価の差を利用した電子ホッピング効果による電気伝導性の向上、▲２▼ガラス表面の化学ポテンシャルの制御による化学耐久性の向上、▲３▼溶融温度、ガラス転移温度を制御した生産性の向上などの利点がある。
（４）ガラス質としているため、層状構造を有した結晶質のものに比べて層間化合物の生成などのインターカレーションによる構造変化を少なくでき、安定した性能を維持できる。
（５）二次電池用カソード電極等に適用した場合、結晶質のものでは２相共存状態がいくつかあるために起電力がステップ状に変化するが、ガラス質では起電力がほぼ一定であり、しかも化学拡散係数を高くできるのでより高いエネルギー密度が得られる。
（６）結晶質のものに比べて薄膜化が容易であり小型化、軽量化ができ、実用性や経済性、機能性、デザイン性にも優れている。
（７）ガラス質としているので、複雑な形状等への被膜形成等が容易にでき、しかも加工性に優れており、種々の形態の半導体素子や反応容器の被膜形成材として利用できる。
【００４３】
請求項２に記載の導電性バナジン酸塩ガラスによれば、請求項１に記載の効果に加えて以下の効果を有する。
（１）ガラス転移温度が特定の低い温度域に設定されているので、導電性バナジン酸塩ガラスを医薬品製造用等の反応容器のライニング等に適用する場合に、施工温度を低くでき、そのグラスライニングの施工を容易に行うことができ、施工性や経済性に優れている。
（２）ガラス転移温度が所定範囲に規定されているので、この導電性バナジン酸塩ガラスにアニーリング処理などを実施する場合に電気伝導性や化学耐久性等の特性の制御性を高めることができ、品質のばらつきが少なく信頼性に優れた半導体デバイスやセンサを製造することができる。
【００４４】
請求項３に記載の導電性バナジン酸塩ガラスによれば、請求項１又は２に記載の効果に加えて以下の効果を有する。
（１）ガラス化の際に溶融温度やガラス転移温度を調整したり、ガラス骨格を構築あるいは修飾するためのガラス化調整成分が所定量含まれているので、化学耐久性と電気伝導性の両者をバランスさせた適正状態に維持させることができ、電気伝導性を備えた防食被覆材としての適用性に優れている。
（２）特に酸化カルシウムや酸化ナトリウム、酸化ケイ素、酸化アルミニウム等をガラス化調整成分として適用する場合には、これらの成分を含有するガラスカレットや発電所等の石炭灰を利用することができ、大量に排出される産業廃棄物の有効活用が図れると共に、安価な原料を用いるので経済性にも優れている。
（３）酸化カリウム、酸化バリウム、酸化ホウ素、酸化ストロンチウム等を含むガラス化調整成分の添加により導電性バナジン酸塩ガラスのガラス転移温度や化学耐久性を効果的に調整でき、化学耐久性と電気伝導性を適正状態に維持させた導電性バナジン酸塩ガラスとすることができ、品質特性等の制御性に優れた材料を提供できる。
【００４５】
請求項４に記載の導電性バナジン酸塩ガラスの製造方法によれば、以下の効果を有する。
（１）原料調整工程を有するので、通常は廃棄されるガラスビンや火力発電所等から排出される石炭灰等を導電性バナジン酸塩ガラスのカルシウムやナトリウム、ケイ素、アルミニウム源となる原料として適用でき、資源の有効活用が図れると共に、廃棄物量を削減して環境保護性にも優れている。
（２）導電性バナジン酸塩ガラスを安価な廃棄物原料を用いて製造できるので、経済性に優れている。
（３）混合物をガラス転移温度以上に保持する熱処理工程を有するので、ガラス骨格そのものの構造の歪み等を緩和させて、電気伝導性や化学耐久性などの特性を所定の範囲に設定でき、制御性に優れる。
（４）導電性バナジン酸塩ガラスをそのガラス転移温度以上の熱処理温度に所定時間保持させて調整するので、バナジウム、ケイ素、鉄、アルミニウム、酸素などから成るガラス骨格のゆがみ（ひずみ）を小さくして、バナジウム４価から５価への電子ホッピングの確率を高め、ガラス半導体や保護被膜としての導電性を増大させることができ、長寿命の保護膜や電極、サーミスタ等を製造できる。
（５）熱処理の温度や保持時間等の熱処理条件とこの熱処理条件により得られる導電性バナジン酸塩ガラスの電気伝導性や化学耐久性との対応関係を用いて、熱処理条件を選択して、その特性を任意に調整することもでき、用途や使用環境に応じた特性を有したサーミスタ素子や伝導性ガラス等を製造できる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a conductive vanadate glass having a good balance between electrical conductivity and chemical durability (corrosion resistance), and a coating material for a reaction vessel, a heat exchanger, a transport pipe, and the like for treating an acidic or alkaline chemical, The present invention relates to a method for producing a conductive vanadate glass that can be suitably used as an adhesive glass, an electrode material, a solid electrolyte, and the like for an electronic device.
[0002]
[Prior art]
Conductive glass is used not only for coating materials for reactors for manufacturing pharmaceuticals, electrode materials, sensors, solid electrolytes, etc., but also uses its electrical conductivity to prevent shells from adhering to hot water drainage pipes and for daily necessities. Applications such as antistatic can be expected.
As this conductive glass, a conductive vanadate glass containing vanadium pentoxide has been developed, and a glass obtained by adding barium oxide, iron oxide, potassium oxide, sodium oxide, or the like as a second component to this glass has been developed. Are known.
Glass containing vanadium has electron conductivity based on hopping of extranuclear electrons, unlike oxide-based glass which is usually an electrically insulating material. For this reason, it shows relatively high electric conductivity. With respect to such a conductive vanadate glass, the following technology is known.
(1) Japanese Patent Publication No. 42-24785 (hereinafter referred to as "A") discloses a glass composition containing at least 50 mol% of vanadium pentoxide, phosphorus pentoxide and barium oxide, and cerium oxide, tin oxide and oxide. A glassy resistance material for a heat-sensitive resistance element to which lead is added is disclosed.
(2) Japanese Patent Publication No. 39-9140 (hereinafter referred to as "B") discloses a glass containing 70 mol% or more of vanadium pentoxide and 5 to 15 mol% of phosphorus pentoxide to which 13 mol% or less of copper oxide is added. A thermistor made from the resulting glass is disclosed.
[0003]
[Problems to be solved by the invention]
However, the conventional conductive vanadate glass has the following problems.
(1) A protective material for a reaction vessel in which a conductive vanadate glass obtained by quenching the melt described in JP-A-B or JP-B-B, etc. is used in a highly corrosive environment such as acid or alkali. When used as, there was a problem that the chemical durability was low, the amount of elution into the solution was large, the consumption was severe, the use could not be performed for a long time, and the practicality was lacking.
(2) If the third component is added to improve the chemical durability, the electrical conductivity is reduced, and it is impossible to maintain both the chemical durability and the electrical conductivity in a balanced state. There were challenges.
(3) Since the electric conductivity is affected by the content and composition of the conductive vanadate glass, and the value varies, the electric conductivity is adjusted within a predetermined range to precisely design the glass semiconductor or the like. Is difficult to perform.
(4) On the other hand, many glass products such as glass bottles for beverages (75% or more) are discarded without being reused, and a large amount of coal ash is released from thermal power plants, and most of them are industrial waste. There was an environmental issue that was disposed of and the effective use of resources did not progress.
[0004]
The present invention solves the above-mentioned conventional problems, and can be applied even in a highly corrosive environment such as an acid or an alkali by maintaining a good balance between electric conductivity and chemical durability. Of conductive vanadate glass suitable for use in sensors such as electrodes, solid electrolytes, thermistors, etc., and it enables precise design by suppressing fluctuations in properties due to its components and its composition, and for beverages An object of the present invention is to provide a method for producing a conductive vanadate glass that can effectively recycle glass products such as glass bottles and industrial waste such as coal ash discharged from a thermal power plant.
[0005]
[Means for Solving the Problems]
The conductive vanadate glass according to claim 1 is made of a glass composition containing 0.1 to 25 mol% of vanadium oxide, and has an electric conductivity of 10 at room temperature. ^-8 -10 ^-4 S ・ cm ^-1 And the amount of elution after immersion in 20% hydrochloric acid at room temperature for 72 hours is 35% by mass or less.
This configuration has the following operation.
(1) Since it is formed of a glass composition containing a predetermined amount of vanadium oxide, a glass skeleton excellent in electric conductivity and chemical durability can be formed, and the electric conductivity is effectively utilized to cause corrosion. It can maintain chemical durability as a protective coating material such as a lining for a chemical reaction vessel used in an environment, or a sensor such as an electrode material, a solid electrolyte, and a thermistor.
(2) Since the electric conductivity and the chemical durability are set within predetermined ranges, it is easy to design when applied to a protective coating, a thermistor, and an electrode element of a reaction vessel or the like exposed to an acid or an alkali, and the design is flexible. Excellent in nature.
(3) Since the glass composition can contain barium, iron, calcium, sodium, silicon, aluminum and the like in addition to vanadium, it can be formed by controlling the skeleton structure of the glass under predetermined conditions. Of electric conductivity by electron hopping effect using difference of valence (valence), (2) improvement of chemical durability by controlling chemical potential of glass surface, (3) production with controlled melting temperature and glass transition temperature There are advantages such as improvement of the performance.
(4) Since it is vitreous, structural changes due to intercalation such as generation of an intercalation compound can be suppressed as compared with crystalline materials having a layered structure, and stable performance can be maintained.
(5) When applied to a cathode electrode for a secondary battery or the like, the electromotive force changes stepwise in a crystalline material because there are some two-phase coexistence states, but the electromotive force is almost constant in a vitreous material. In addition, since the chemical diffusion coefficient can be increased, a higher energy density can be obtained.
(6) Compared to crystalline ones, it can be easily formed into a thin film, can be reduced in size and weight, and is excellent in practicality, economy, functionality, and design.
(7) Since it is made of glass, it is easy to form a film into a complicated shape and the like, and it is excellent in workability, and can be used as a film forming material for various forms of semiconductor elements and reaction vessels.
[0006]
Here, vanadium is a constituent element for forming the main skeleton of the oxide-based glass, and its oxidation number changes to 2, 3, 4, 5, etc., so that the probability of hopping of extranuclear electrons can be increased. it can.
It is desirable that the content of vanadium oxide in the conductive vanadate glass be in the range of 0.1 to 25 mol%, preferably 1 to 10 mol%. This depends on the application conditions, but as the content of vanadium oxide becomes less than 1 mol%, it becomes difficult to maintain the glass skeleton containing vanadium as a main component, and the electric conductivity is set within a predetermined range. Tends to be difficult to maintain, and conversely, as the amount exceeds 10 mol%, the amount of subcomponents relatively decreases, so that the electric conductivity, chemical durability, optical properties, mechanical properties, etc. of these subcomponents This is because there is a tendency for the control function to decrease, and these tendencies become more pronounced when the content is less than 0.1 mol% or more than 25 mol%.
[0007]
Vanadium pentoxide is V ₂ O ₅ It has a layered crystal structure consisting of pyramids, and this has potassium oxide (K ₂ O) and sodium oxide (Na) ₂ When vitrification is performed by adding O), the glass skeleton becomes one-dimensional. However, by adding barium oxide (BaO) or the like to vanadium pentoxide, the glass skeleton can be formed three-dimensionally. In this way, the electrical conductivity and the chemical durability can be maintained in a balanced state, and the conductive vanadate glass can be effectively functioned as a chemical anticorrosion coating material, a thermistor, a capacitor, a magnetic material, or the like.
[0008]
Barium, iron, silicon, aluminum, and the like can be applied as other components of the conductive vanadate glass. Barium is a constituent element added to make the glass skeleton of a two-dimensional vanadium oxide three-dimensional.
Iron is an element having five electrons in a 3d orbital, and it is highly likely that these electrons contribute to the electrical conductivity of the glass skeleton. That is, in the conductive vanadate glass, it is estimated that five valence electrons on the 3d orbital of Fe also contribute to electron hopping from V (IV) to V (V). As in the case of barium oxide, the conductivity can be adjusted by changing the concentration of iron oxide, and is added as a component for adjusting the electrical conductivity.
The content of iron oxide in the conductive vanadate glass is desirably in the range of 1 to 20 mol%. This depends on the application conditions, but if the content of iron oxide is less than 1 mol%, it tends to be difficult to maintain the electron hopping effect by iron, and if it exceeds 20 mol%, the light transmittance etc. This is because adverse effects such as a decrease in the optical characteristics of the device appear.
[0009]
The electrical conductivity of the conductive vanadate glass is 10 at room temperature of 25 ° C. ^-8 -10 ^-4 S ・ cm ^-1 , Preferably 10 ^-7 -10 ^-5 S ・ cm ^-1 It is desirable to be within the range. This varies depending on the type and capacity of the electrode or thermistor to which the conductive vanadate glass is applied, the application, and the like. ^-7 S ・ cm ^-1 As the size becomes smaller, there is a tendency that the operation efficiency of various elements is reduced and the operation becomes difficult, and conversely, the electric conductivity becomes 10 ^-5 S ・ cm ^-1 As the amount of vanadium increases, the chemical durability, mechanical strength, and the like deteriorate due to the relative increase in the amount of vanadium, and the electrical characteristics of the semiconductor tend to be lost. ^-8 S ・ cm ^-1 Smaller or 10 ^-4 S ・ cm ^-1 This is because the larger the size, the more remarkable.
[0010]
The chemical durability of the conductive vanadate glass is evaluated based on the elution amount of a sample immersed in a corrosive liquid of a specified concentration for a specified time. That is, for example, the measurement sample can be immersed in a container filled with 20% hydrochloric acid having a mass 10 times the mass of the measurement sample, and the evaluation can be made based on the elution amount after immersion at room temperature for 72 hours.
As for the chemical durability evaluated in this way, the elution amount is desirably 35% by mass or less, preferably 5% by mass or less. This depends on the application conditions such as the type and temperature of the corrosive liquid that comes into contact with the conductive vanadate glass, but in general, as the amount of elution exceeds 5% by mass, the consumption during use becomes severe and practical use Above, there is a tendency that it is difficult to apply as a protective film or a sensor, and it tends to be difficult to set the electric conductivity in a predetermined range in a well-balanced manner. This is because it becomes remarkable.
The chemical durability is evaluated using the amount of elution under such measurement conditions as an index, but the measurement is performed under different measurement conditions such as the concentration, temperature, immersion time, and liquid volume of the corrosive liquid. Even in the case of the test described above, it can be evaluated by converting to a dissolution amount corresponding to the case of immersion in 20% hydrochloric acid using a control table comparing the correlation between the two.
[0011]
A conductive vanadate glass having a predetermined electrical conductivity and chemical durability can be produced, for example, using the following glass composition. Vanadium oxide 0.1 to 25 mol%, barium oxide 0.5 to 10 mol%, iron oxide 0.5 to 5 mol%, sodium oxide 1 to 25 mol%, calcium oxide 2 to 25 mol%, silicon oxide 40 to After the glass composition containing 70 mol% or the like is heated and melted in a platinum crucible or the like, it can be obtained by quenching. Further, the vitrified product is maintained at an annealing temperature such as a temperature equal to or higher than the glass transition temperature of the mixture and equal to or lower than the softening temperature for a predetermined time, and is manufactured by adjusting the electrical conductivity and chemical durability of the resulting glass composition. You can also.
Here, the content of vanadium oxide is 0.1 to 25 mol%. Within this range, the glass skeleton containing vanadium as a main component is maintained, the electrical conductivity is excellent, and the functions such as chemical durability, optical properties, chemical properties, and mechanical properties are excellent.
Barium oxide is excellent in electrical conductivity and chemical durability when the content is 0.5 to 10 mol%. The chemical durability is improved as the amount becomes less than 0.5 mol%, but the tendency to vitrification is observed. Also, as the ionic radius of barium becomes larger as the amount exceeds 10 mol%, the chemical durability is reduced. There is a tendency to deteriorate.
When the content of iron oxide is 0.5 to 5 mol%, the molding temperature is reduced and the electric conductivity is improved. When the amount is less than 0.5 mol%, the contribution to electron hopping tends to be hardly obtained, and when the amount is more than 5 mol%, the chemical durability tends to decrease, which is not preferable.
Although the chemical durability improves as the amount of sodium oxide or calcium oxide decreases below the lower limit of mol%, glass production tends to be difficult and non-uniform, and as the amount exceeds the upper limit of mol%, electrical conductivity increases. Although the degree is improved, the chemical durability is deteriorated, which is not preferable.
Silicon oxide tends to have an excessively high coefficient of thermal expansion as the amount of silicon oxide becomes less than 40 mol%, and the chemical durability of glass tends to be remarkably reduced. This is not preferable because the temperature tends to be high and energy saving tends to be lacking.
With this composition, a conductive vanadate glass having a good balance between electric conductivity and chemical durability can be obtained.
[0012]
The conductive vanadate glass according to the second aspect is configured such that in the invention according to the first aspect, the glass transition temperature of the glass composition is 400 to 700 ° C.
With this configuration, the following operation is obtained in addition to the operation described in the first aspect.
(1) Since the glass transition temperature is set in a specific low temperature range, the melting temperature can be lowered when the conductive vanadate glass is applied to a lining material of a reaction vessel for manufacturing pharmaceuticals, etc. The glass lining having a high thermal expansion coefficient can be easily constructed, and is excellent in workability and economy.
(2) Since the glass transition temperature is specified in a predetermined range, when the conductive vanadate glass is subjected to an annealing treatment or the like, controllability of characteristics such as electric conductivity and chemical durability can be improved. In addition, it is possible to manufacture a semiconductor device or a sensor having small variations in quality and excellent reliability.
[0013]
Here, the glass transition temperature is preferably in the range of 300 to 700 ° C, preferably 400 to 700 ° C, and more preferably 400 to 600 ° C. This depends on the type, shape, and composition of the device or device to which the conductive vanadate glass is applied, but generally, as the glass transition temperature becomes lower than 400 ° C., the chemical durability and the mechanical durability become lower. On the contrary, as the temperature exceeds 600 ° C., the viscosity of the molten glass increases, and it tends to be difficult to form a uniform lining layer in a glass lining or the like. This is because the temperature becomes lower or the temperature becomes higher when the temperature exceeds 700 ° C.
The glass transition temperature can be set by increasing or decreasing the amount of addition of an alkali component such as sodium or potassium in the conductive vanadate glass. This addition amount can be determined based on a correlation table indicating the relationship between the addition amount experimentally obtained in advance and the glass transition temperature, a theoretical calculation, or the like.
[0014]
The conductive vanadate glass according to claim 3 is the invention according to claim 1 or 2, wherein the glass composition includes calcium oxide, sodium oxide, potassium oxide, barium oxide, boron oxide, and strontium oxide. It is configured to contain about 10 to 40 mol% of a vitrification adjusting component composed of any one or a combination of these components.
With this configuration, the following operation is obtained in addition to the operation of the first or second aspect.
(1) Since a certain amount of a vitrification-adjusting component for adjusting a melting temperature or a glass transition temperature or constructing or modifying a glass skeleton at the time of vitrification is contained, chemical durability and electric conductivity are included. Can be maintained in a proper state in which both are balanced, and are excellent in applicability as an anticorrosion coating material having electric conductivity.
(2) In particular, when calcium oxide or sodium oxide is used as a vitrification controlling component, glass cullet containing these components and coal ash from power plants can be used, and a large amount of industrial waste is discharged. Since the material can be effectively used and inexpensive raw materials can be used, the economy is also excellent.
(3) The glass transition temperature and the chemical durability of the conductive vanadate glass can be effectively adjusted by adding a vitrification adjusting component including potassium oxide, barium oxide, boron oxide, strontium oxide, etc., thereby improving the chemical durability and electric power. A conductive vanadate glass having conductivity maintained in an appropriate state can be obtained, and a material excellent in controllability such as quality characteristics can be provided.
[0015]
Here, as the vitrification adjusting component, an alkali metal, an alkaline earth metal, or the like can be applied. In addition to being a component constituting the glass skeleton in the oxide glass, it has a function of balancing chemical durability and electrical conductivity. Have.
The vitrification adjusting component is preferably in the range of 10 to 40 mol%, preferably 15 to 30 mol%. This depends on the application location of the conductive vanadate glass, but as the vitrification adjusting component is less than 15 mol%, glass formation becomes difficult. Conversely, as the content exceeds 30 mol%, chemical durability and mechanical durability increase. The strength and the like tend to decrease, and the use at a practical level tends to be difficult. This is because these tendencies become less pronounced when the amount is less than 10 mol% or more than 40 mol%.
In particular, when sodium oxide is used as the vitrification adjusting component, the content is preferably in the range of 1 to 30 mol%, more preferably 10 to 20 mol%. This depends on the content of vanadium oxide and other components, but generally, as the content of sodium oxide becomes less than 10 mol%, the melting temperature and the vitrification temperature increase, and The productivity tends to decrease, and conversely, as it exceeds 20 mol%, the chemical durability tends to decrease and the use tends to become difficult, and these tend to be less than 1 mol% or 30 mol%. Is more remarkable when the value exceeds.
[0016]
A method for producing a conductive vanadate glass according to claim 4 is the method for producing a conductive vanadate glass according to any one of claims 1 to 3, wherein vanadium, barium, and iron are used. A raw material adjustment step of mixing an alkali-containing composition such as a glass cullet crushed from a glass bottle or a coal ash discharged from a combustion device into a vanadate composition containing the same, and a heat treatment temperature of the glass transition temperature or higher by melting the mixture. Is provided.
This configuration has the following operation.
(1) Since it has a raw material adjustment step, it is possible to apply normally discarded glass bottles and coal ash discharged from thermal power plants, etc., as raw materials for the calcium, sodium, silicon, and aluminum sources of conductive vanadate glass. In addition to effective utilization of resources, the amount of waste can be reduced and the environmental protection is excellent.
(2) Since the conductive vanadate glass can be manufactured using inexpensive waste materials, it is excellent in economical efficiency.
(3) Since it has a heat treatment step of maintaining the mixture at a temperature equal to or higher than the glass transition temperature, it is possible to relax the structural distortion of the glass skeleton itself and to set properties such as electric conductivity and chemical durability within a predetermined range. Excellent in nature.
(4) Since the conductive vanadate glass is maintained at a heat treatment temperature equal to or higher than its glass transition temperature for a predetermined time, the distortion (strain) of the glass skeleton composed of vanadium, silicon, iron, aluminum, oxygen, etc. is reduced. As a result, the probability of electron hopping from vanadium tetravalent to pentavalent can be increased, the conductivity as a glass semiconductor or a protective film can be increased, and a long-life protective film, electrode, thermistor, and the like can be manufactured.
(5) The heat treatment conditions are selected by using the correspondence between the heat treatment conditions such as the heat treatment temperature and the holding time and the electrical conductivity and chemical durability of the conductive vanadate glass obtained under the heat treatment conditions. The characteristics can be arbitrarily adjusted, and a thermistor element, a conductive glass, or the like having characteristics according to the use or the use environment can be manufactured.
[0017]
Here, as the vanadate composition, a vanadate oxide containing vanadium, barium, iron, etc., for example, 15 mol% BaO.70 mol% V ₂ O ₅ ・ 15mol% Fe ₂ O ₃ Oxides having the following composition, vanadium oxide, barium oxide, iron oxide mixed at a predetermined ratio, and those obtained by pulverizing the melt to a predetermined particle size, for example, a particle size of about 1 to 500 μm, etc. Is applicable.
Examples of the alkali-containing composition include glass cullets containing sodium oxide, calcium oxide, silicon oxide, and the like, which are obtained by pulverizing a glass bottle for drinks such as juice and cola having a substantially constant component composition to, for example, 100 to 5000 μm, or a thermal power plant. For example, fly ash (coal ash) containing calcium oxide, silicon oxide, aluminum oxide, or the like discharged by the method can be used.
The mixing ratio of the glass composition is such that (a) glass cullet or silicate glass or coal ash is 35 to 95% by mass, (b) sodium oxide, 0 to 20% by mass of at least one kind of potassium, 0 to 15% by mass of (c) calcium oxide, 0 to 50% by mass of (d) silicon oxide, 0 to 30% by mass of (e) vanadium oxide, (f) ) Boron oxide is added in an amount of 0 to 10% by mass.
Here, the value of the electric conductivity of the vanadate composition tends to decrease remarkably as the amount becomes less than 5% by mass, and the chemical durability tends to decrease as the amount becomes more than 35% by mass. It is not preferred.
(A) The glass cullet, silicate glass, and coal ash tend to decrease in chemical durability as the amount becomes less than 65% by mass, and the vanadate composition becomes greater when the amount exceeds 95% by mass. This is not preferable because there is a tendency that the amount of materials is small and the softening point of glass tends to increase to lower the productivity. When glass cullet is used, the amount of electricity (cost) required for manufacturing glass can be suppressed by 10% or more, so that 75 to 90% by mass is suitably used. The addition of glass cullet also contributes to the recycling of waste. Incidentally, the prescribed amount of the glass cullet may be replaced with silicon oxide. In this case, as shown in Table 2, the glass may be designed such that the amount of silicon oxide in the manufactured glass is about 55 mol% to 75 mol%. It was also found that when the mixing ratio of glass cullet (a) and silicon oxide (b) was (a) / (b) = 40 to 60% by mass, electric conductivity and chemical durability could be remarkably improved. When glass cullet is used, a predetermined amount of sodium oxide, potassium oxide, lithium oxide, calcium oxide, or the like can be added to the system to improve electrical conductivity and chemical durability while maintaining a good balance.
Further, by adding 5% by mass of boron oxide, electric conductivity and chemical durability can be improved in a well-balanced manner.
Since silicate glass contributes to improvement of chemical durability and ion conduction of sodium, potassium, lithium and the like, 80 to 90% by mass is suitably used. When silicate glass is used, the addition of 10 to 20% by mass of vanadium oxide can improve the electrical conductivity and chemical durability in a well-balanced manner. This is because electric conductivity is improved by electron conduction by hopping of valence electrons on vanadium atoms.
Since coal ash has the same effect as a glass bottle and contributes as a silicate raw material, 70 to 90% by mass is suitably used. In addition, when using coal ash, electric conductivity and chemical durability can be improved in a well-balanced manner by adding a predetermined amount to the system. Coal ash is industrial waste emitted from thermal power plants and other sources, and its effective use is important for both resource energy and environmental conservation.
(B) Sodium oxide, potassium oxide, lithium oxide and the like can lower the glass production temperature as compared with the case of using silicon oxide alone, which is energetically advantageous. In addition, sodium ions, potassium ions, lithium ions, and the like contribute to the ionic conduction of the glass, so that 5 to 15% by mass is particularly preferably used in a system using glass cullet. Thereby, electric conductivity and chemical durability can be improved in a well-balanced manner.
(C) Like other Group 2 elements of the periodic table, calcium oxide is present in the vicinity of oxygen in the gap between the glass skeletons and contributes to stabilizing the glass structure. In the system used, 5 to 10% by mass is suitably used. Electric conductivity and chemical durability can be improved in a well-balanced manner.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention is to produce a conductive vanadate glass using a glass bottle for soft drinks, coal ash discharged from a thermal power plant or the like as a part of the raw material, whereby the conductive vanadate is produced. The chemical durability and electric conductivity of the glass are appropriately adjusted.
The conductive vanadate glass according to one embodiment of the present invention is manufactured by the following manufacturing method.
First, a vanadate composition such as glassy containing vanadium adjusted to a predetermined particle size, and various glass raw materials containing components such as vanadium, calcium, sodium, silicon, and aluminum, and coal ash are selected at a predetermined ratio. Mix. This mixture is heated to a temperature equal to or higher than the melting point to be melted, subjected to a predetermined heat treatment as required, and rapidly cooled to obtain a glass composition having both predetermined chemical durability and electric conductivity.
If necessary, the glass composition is kept at a temperature of a heat treatment not lower than its glass transition temperature, not higher than its crystallization temperature or not higher than its softening temperature for a predetermined time, and the conductive composition adjusted to a predetermined electric conductivity and chemical durability is used. It is also possible to produce a hydrophilic vanadate glass. Hereinafter, an example of this manufacturing method will be described in more detail.
[0019]
The vanadate composition used as a raw material here is a vitrified raw material containing 70 mol% of vanadium oxide, 15 mol% of barium oxide, and 15 mol% of iron oxide, or a vitrification raw material composed of a mixture thereof.
This composition includes barium for three-dimensionally converting a glass skeleton made of vanadium, and iron for promoting an electron hopping effect by 3d electrons. Note that an element of the second group of the periodic table (Mg) or phosphorus pentoxide (P ₂ O ₅ The glass skeleton can also be made three-dimensional by adding ()) to vanadium pentoxide, which is the main component, as a subcomponent. Therefore, BaO in the vitreous vanadate composition is replaced with MgO or P ₂ O ₅ Or an oxide of Ca located between Ba and Mg on the periodic table can be expected to have an effect of increasing electric conductivity.
When preparing such a vanadate composition, for example, 15 mol% of reagent grade barium oxide (BaO) and vanadium pentoxide (V ₂ O ₅ ) Is 70 mol%, and iron oxide (Fe ₂ O ₃ ) Is weighed using a direct reading balance or the like so as to be 15 mol%.
This mixture is transferred to a platinum crucible or the like, and heated in an electric furnace at 1000 ° C. for 60 minutes to be melted. This is immediately quenched with ice water or the like (the outside and the bottom of the platinum crucible are immersed in ice water) to obtain a vanadate glass composition having predetermined chemical durability and electrical conductivity.
[0020]
Note that the heat treatment method includes the following two methods.
{Circle around (1)} A method in which the temperature of an electric furnace or the like is set in advance to a target temperature, and when the temperature of the electric furnace or the like becomes constant, a glass sample stored at room temperature is added. A feature of this method is that the heating time can be controlled relatively accurately. As soon as the target time has elapsed, the glass is immediately taken out of the electric furnace or the like, and the outside of the container such as a platinum crucible is rapidly cooled with ice water or the like. By performing the rapid cooling as described above, the heat treatment (heating) time from the start of heating can be accurately controlled, so that the structure of the glass can be relaxed with high accuracy. Thereby, the electric conductivity can be controlled with high precision, and the glass can be provided with required electric conductivity and chemical durability.
{Circle around (2)} A method of slowly heating the glass from room temperature. This is a method in which the heating rate of an electric furnace or the like is set to a constant (arbitrarily), heated to an intended temperature for an appropriate time, and then gradually cooled to room temperature or near room temperature at a constant rate. .
By the above methods (1) and (2), the distortion (strain) of the glass skeleton can be reduced or eliminated, and these can be combined.
For example, there is a method in which glass is put into an electric furnace which has been heated to a target temperature in advance, and after a certain period of time, cooled slowly to around room temperature.
[0021]
As the vitrification adjusting component for producing the conductive vanadate glass, glass cullet having a substantially constant composition adjusted to a predetermined particle size, coal ash discharged from a thermal power plant, or the like can be used.
Here, as glass cullet, (1) pulverized glass bottles for soft drinks (glass bottles for real gold) manufactured by Coca-Cola Laborers Co., Ltd .; The silicate glass used was applied.
Incidentally, (1) glass bottles have a chemical composition of sodium oxide: 16% by mass, calcium oxide: 10% by mass, silicon oxide: 74% by mass, and (2) silicate glass mainly contains silicon oxide. Those having a general chemical composition (silicon oxide: about 65 to 75% by mass) were used.
As a raw material such as calcium, silicon, and aluminum as a vitrification adjusting component, coal ash discharged from a thermal power plant using coal as a fuel was used. The typical chemical composition of coal ash is calcium oxide: average 4% by mass, iron oxide: average 3% by mass, aluminum oxide: average 24% by mass, silicon oxide: average 62% by mass, and other metal oxides: average 7% by mass. there were.
In addition, as a raw material serving as a sodium source of the conductive vanadate glass, sodium oxide, sodium carbonate, sodium nitrate, and the like were blended to adjust the total sodium content within a predetermined range.
In addition, in addition to the above, the raw material components to be added as vitrification components include aluminum oxide, boron oxide, potassium oxide, lithium oxide, magnesium oxide, strontium oxide, lead oxide, phosphoric acid, titanium oxide, zinc oxide, and zirconium oxide. Etc. can be applied as needed
By using aluminum oxide as a glass component, generation of silica-based devitrification can be suppressed to prevent phase separation, and chemical durability can be increased, and elastic modulus and hardness can be increased.
Boron oxide or the like itself forms a network structure and can serve as a glass, and silicate glass also serves as a network component, and is suitable for producing a glass having reduced viscosity and high chemical durability.
[0022]
Table 1 is a composition table showing a glass raw material composition in each of Examples 1 to 20 and Comparative Examples 1 to 4 in the embodiment. Mol%).
[0023]
[Table 1]

[0024]
[Table 2]

[0025]
The glass transition temperature (Tg) and the melting temperature of each sample of the glass composition prepared as described above were determined by performing differential thermal analysis (DTA), differential scanning calorimetry (DSC), and the like. They are shown in Table 3. The rate of temperature rise in the DTA measurement was set at 15 ° C. per minute.
[0026]
[Table 3]

[0027]
Heating a glass above its glass transition temperature causes cutting of the glass skeleton, reconstruction of the skeleton that forms the glass, and rearrangement of fragments. However, when the glass is heated for a long time at a temperature equal to or higher than the glass transition temperature, a crystal phase precipitates in the glass phase, and the glass phase grows, so that the glass becomes a crystallized glass (glass ceramic), and the electrical conductivity is increased. And light transmittance etc. are reduced. Therefore, the holding time at the annealing treatment temperature varies depending on the glass processing amount, the heat capacity of the heating device, and the like, but within a range where the predetermined electric conductivity can be maintained and such crystallization does not occur. For example, it is desirable to set the time in the range of 10 minutes to 180 minutes, preferably 20 to 60 minutes.
The heat treatment temperature is set in the range from the glass transition temperature to the crystallization temperature (the temperature at the high-temperature end point of the foot of the crystallization exothermic peak in the differential thermal analysis or the temperature at the center of the exothermic peak). If the heat treatment time is short, distortion (strain) of the glass skeleton can be reduced before the crystal phase is precipitated (before the crystallized glass), so that so-called structural relaxation can be caused. Conductive vanadate glass whose degree has been increased to a predetermined range can be produced.
[0028]
The electrical conductivity of a sample of the glass composition subjected to the heat treatment such as annealing was measured as follows.
At the time of measurement, a glass piece with a sample thickness of 1 mm or less of the glass composition was used, and a value was obtained at room temperature by applying a DC two-terminal method, a DC four-terminal method, or an AC four-terminal method. In this measurement, an electrode was used in which a lead wire was fixed to the glass surface using a molten metal indium or metal silver paste.
[0029]
The chemical durability of each sample was determined by placing an airtight container containing hydrochloric acid and sodium hydroxide solution of a predetermined concentration in a thermostat kept at a set temperature of 30 ° C., and weighing it in advance in this corrosive solution. The sample was immersed, the sample taken out after a predetermined time was weighed, and the elution amount was determined from the weight loss. In the present embodiment, as indicators of chemical durability, (1) the amount of elution after immersion in 20% hydrochloric acid for 72 hours, (2) the amount of elution after 240 hours in 20% hydrochloric acid, and (3) 1 molar sodium hydroxide solution The amount eluted after immersion in medium for 72 hours and the amount eluted after immersion in (4) 1 molar sodium hydroxide solution for 240 hours were measured.
Table 3 shows data such as electrical conductivity and chemical durability of each sample obtained as described above.
Hereinafter, Examples 1 to 20 and Comparative Examples 1 to 4 will be described with reference to Tables 1 to 3.
[0030]
(Examples 1 to 9)
As shown in Table 1, in Examples 1 to 9, the amount of the vanadate composition was fixed at 10% by mass, and the amount of the glass bottle was changed in the range of 90 to 40% by mass to oxidize the shortage. It is obtained by blending with sodium, potassium oxide, calcium oxide, and the like.
The data of Examples 1 to 9 excluding Example 5 are obtained by melting the mixture blended at the predetermined ratio at 1000 ° C. for 1 hour and then vitrifying the mixture. Shows the data obtained by melting for 1 hour.
As shown in Table 3, in Examples 2 to 6, sodium carbonate was added so that the glass transition temperature was 521 ° C or lower, and the amount of sodium oxide in the raw materials was adjusted. At this time, sodium carbonate is (Na ₂ CO ₃ → Na ₂ O + CO ₂ Due to the reaction of ↑), Na ₂ It becomes O. (Where Na ₂ O molecules do not exist alone; ⁻ ... Na ⁺ Builds ionic bonds and plays the role of network modifying ions. )
As shown in the data of Table 2, the composition of the raw materials was adjusted to adjust the content of calcium oxide and sodium oxide in the glass to a predetermined range, the arrangement of each ion in the glass was determined, and a predetermined chemical durability was obtained. A glass composition having both properties and electrical conductivity can be obtained.
[0031]
As shown in the data of chemical durability in Table 3, the chemical durability of Example 1 (conductive vanadate glass using glass bottle: 90% by mass and vanadate composition: 10% by mass as a raw material) is extremely high. You can see that. In addition, Example 2 (glass bottle: 85% by mass / vanadate composition: 10% by mass / sodium oxide: 5% by mass) and Example 3 (glass bottle: 80% by mass / vanadate composition: 10% by mass) % / Sodium oxide: 10% by mass) in practical use.
The chemical durability of Example 4 (glass bottle: 75% by mass, vanadate composition: 10% by mass, sodium oxide: 15% by mass) is not so good as compared with those of Examples 1 to 3, It can be seen that if the concentration is not so high, it can be sufficiently used.
Example 5 shows an example in which boron oxide was added as a vitrification adjusting component in an amount of 5% by mass. ^-7 S ・ cm ^-1 Although it is low in the examples, the conductive vanadate glass having the electric heating property for a heater or the like, and having a high coefficient of thermal expansion, heat resistance, and chemical durability can be obtained by adding boron oxide. I understand.
[0032]
In Example 6, as (the glass bottle: 40% by mass, the vanadate composition: 10% by mass, the sodium oxide: 10% by mass, and the silicon oxide: 40% by mass), the blending amount of the glass bottle was relatively reduced, and the amount was insufficient. In this example, an experimental example was shown in which the silicon oxide was supplemented with silicon oxide. ^-7 S ・ cm ^-1 It can be seen that the chemical durability is high and the elution amount after 72 hours in 20% HCl is as small as 0.03% by mass.
Examples 7 to 9 are based on a glass bottle: 80% by mass and a vanadate composition: 10% by mass, based on (1) 10% by mass of potassium oxide, (2) 10% by mass of calcium oxide, and (3), respectively. A mixture of 5% by mass of potassium oxide and 5% by mass of calcium oxide is blended. The elution amounts after 72 hours in 20% HCl in Examples 7 to 9 were (1) 0.08% by mass, (2) 0.10% by mass, and (3) 0.09% by mass, respectively. It can be seen that the durability is good and the device can be used for an electric device exposed to a corrosive atmosphere.
[0033]
In Comparative Example 1, the compounding amount of the vanadate composition was increased to 80% by mass, and 10% by mass of a glass bottle and 10% by mass of sodium oxide were added thereto. In this case, the electric conductivity was reduced to a predetermined level. However, the elution amount after 72 hours in 20% HCl becomes as large as 100% by mass, and the chemical durability is lowered. To maintain the chemical durability in a predetermined range, as shown in Table 3, oxidation is performed. This suggests that there is an upper limit to the amount of vanadium. The electrical conductivity was initially 16 × 10 ^-7 S ・ cm ^-1 However, it was found that the value of the electric conductivity could be adjusted by further adding a predetermined heat treatment to this.
That is, when this sample was annealed in air at 370 ° C. for 30 minutes, its electrical conductivity was 24 × 10 ^-7 S ・ cm ^-1 Increased to 25 × 10 ^-7 S ・ cm ^-1 14 × 10 after heat treatment for 2 hours ^-7 S ・ cm ^-1 Has dropped. As described above, the heat treatment time and the heat treatment temperature each have an appropriate range, and by appropriately setting these set conditions, a conductive vanadate glass having required chemical durability and electric conductivity can be manufactured.
[0034]
Comparative Example 2 is an example in which the glass bottle is 70% by mass and the vanadate composition is 30% by mass. In this case, since the mixing ratio of vanadium oxide and the like is not appropriate, the elution amount after immersion in hydrochloric acid of 20% concentration for 72 hours, which is an index of chemical durability, is 40.7% by mass, which is more than the practically usable limit. You can see that it is higher.
[0035]
As described above, from the data of the electrical conductivity (electrical conductivity σ) in Table 3, 10 ^-5 -10 ^-7 S ・ cm ^-1 And a relatively high electric conductivity in the range of the above, indicating that it can be applied as a glass material having excellent electric conductivity in addition to the chemical durability.
As described above, the conductive vanadate glass obtained by combining the glass bottle and the vanadate composition has extremely excellent chemical durability, and the design and control of the glass transition temperature and the like are easy. Therefore, it can be used as an antistatic material to release the static electricity in reaction vessels used in the production of pharmaceuticals, etc., utilizing this electrical conductivity and chemical durability, and also to attach shells to hot drainage pipes and the like. It can also be used as a preventive material.
[0036]
As a method for forming the conductive vanadate glass in such a case, a method such as a vacuum evaporation method, a sputtering method, or an ion plating method, or a method in which molten glass is blown onto a substrate and solidified, or the like. Method can be applied.
The conductive vanadate glass can be used as a heater for window glass of buildings and cars by applying electric heating by using the appropriate electric conductivity of the conductive vanadate glass, and is also effective in preventing fogging and preventing dew condensation. Expected to be. In this example, a glass bottle for soft drinks made by Coca-Cola Laboratories was used as a glass bottle as a raw material. However, the present invention is not limited to this, and other glass bottles can be expected to achieve the same or better results.
[0037]
(Examples 10 to 15)
In Examples 10 to 15 and Comparative Example 3, based on 10% by mass (or 30% by mass) of the vanadate composition, a vitrification adjusting component such as coal ash, sodium oxide, potassium oxide, or calcium oxide was added thereto. An experimental example in the case is shown.
Example 10 is a mixed system of coal ash: 90% by mass and vanadate composition: 10% by mass, and Example 15 is a mixed system of coal ash: 70% by mass and vanadate composition: 30% by mass. Examples 11 to 14 show a series in which a vitrification adjusting component is blended in addition to the coal ash and the vanadate composition.
In contrast, Comparative Example 3 shows data of a mixed system in which the blending ratio of coal ash: 75% by mass, the vanadate composition: 10% by mass, and sodium oxide: 15% by mass, heat treatment conditions, and the like are inappropriate. .
As in Examples 10 to 15, a glass system using coal ash, particularly Example 10 (glass of coal ash: 90% by mass, vanadate composition: 10% by mass) is used not only in hydrochloric acid but also in sodium hydroxide solution. It can be seen that the sample also shows high chemical durability.
In Example 11 (coal ash: 80% by mass, vanadate composition: 10% by mass, sodium oxide: 10% by mass) to which an alkali component and the like were added, there was no major problem in the chemical durability, but the comparison was made. As in Example 3, when the alkali component (sodium oxide) is 15% by mass or more, the elution amount in 20% hydrochloric acid increases.
As described above, the chemical durability changes depending on the composition of each raw material. In Comparative Example 3, it can be seen that the chemical durability is significantly deteriorated because the amount of sodium oxide exceeds the specified amount.
Thus, waste such as coal ash discharged from a thermal power plant or the like can be added to a vanadate composition and applied as a raw material for calcium, silicon, aluminum, or the like. Furthermore, it was revealed that conductive vanadate glass can be produced using inexpensive waste materials, and that it is excellent in economic efficiency and environmental protection.
[0038]
(Examples 16 to 20)
In Examples 16 to 20, a conductive vanadate glass was produced by blending a silicate glass used as a surface protective material of a reaction vessel (made of iron) for a pharmaceutical preparation into a vanadate composition as a part of a raw material. This is an experimental example.
The conductive vanadate glasses of Examples 16 to 20 were obtained by mixing a vanadate composition (BaO: 15 mol%, V ₂ O ₅ : 70 mol%, Fe ₂ O ₃ : 15 mol%) or a mixture of vanadium oxide at a constant mass ratio was melted at 1400 ° C for 1 hour. Table 3 shows the measurement results of evaluating the chemical durability and electric conductivity of this sample. In addition, the data in the case of only silicate glass are shown as Comparative Example 4.
[0039]
As can be seen from Table 3, the conductive vanadate glasses of Examples 16 to 19 did not show a significant difference in chemical durability as compared with those of Examples 1 to 15 and Comparative Example 4, and were used for chemical reaction vessels. It turns out that it is a level which can be used practically as a protective coating material.
In Example 18 (silicate glass: 80% by mass, vanadate composition: 20% by mass), the elution amount in 20% HCl for 72 hours was 4.35% by mass, and the chemical durability was slightly lowered. However, given the high concentration of hydrochloric acid used in the test, it is often at a level that can be used with almost no problem.
Further, Examples 16 to 20 show relatively high electric conductivity among all Examples, and can be expected to be used in a wide range of fields as a glass semiconductor.
The system of Example 19 (silicate glass: 90% by mass, vanadium oxide: 10% by mass) and Example 20 (silicate glass: 80% by mass, vanadium oxide: 20% by mass) are composed of vanadate. This was prepared for comparison with the system using the composition (Examples 16 to 18). From the comparison of these data, it is not necessary to use the vanadate composition as a starting material, and to add the corresponding reagents and the like. It is shown that a conductive vanadate glass having a predetermined chemical durability and electrical conductivity can be produced by adjusting the overall chemical composition to a predetermined range, appropriately setting heat treatment conditions, and the like. ing.
In Example 20 in which vanadium oxide was 20% by mass, the elution amount in 20% HCl, which is an index of the chemical durability, was 29.6% by mass, which was higher than that in Examples of other systems. This is a level sufficiently applicable for an electric device used in an atmosphere having relatively low corrosiveness.
[0040]
As shown in Table 3, the glass transition temperature in Examples 1 to 20 is in the range of 484 ° C. (Example 4) to 670 ° C. (Example 10), and the softening temperature is 574 ° C. (Example 4). 819 ° C. (Example 11). From these data, it can be seen that the flowability and the like of the melted glass when the conductive vanadate glass is applied as a lining material for a reaction vessel can be secured in a favorable range, and that the workability is excellent.
As described above, the conductive vanadate glass prepared by combining the silicate glass and the vanadate composition or the vanadium oxide used in the surface of the reaction vessel for drug production at a predetermined ratio has excellent chemical durability. The design and control of the glass transition temperature and the like are also easy. Furthermore, 100,000 times (× 10 4) compared to the silicate glass shown in Comparative Example 4. ⁵ ) Or higher electrical conductivity (10 ^-7 -10 ^-4 S ・ cm ^-1 ), It can be effectively used as a heating element for energized heating, and can be used as an antistatic material for a reaction vessel for manufacturing pharmaceuticals, thereby enhancing safety during a reaction operation. It can also be used to prevent shells from adhering to hot drainage pipes, and because of its moderate conductivity, it can be used as an electric heater to prevent clouding and dew condensation on glass for buildings and cars.
[0041]
Since the conductive vanadate glass and the method for producing the same according to the embodiment of the present invention are configured as described above, they have the following functions.
(1) An electrically conductive protective coating material for a chemical reaction vessel used in a corrosive environment, an electrode material, a solid electrolyte, and the like, which can form a glass skeleton excellent in electric conductivity and chemical durability. Chemical durability as a sensor such as a thermistor can be maintained.
(2) Waste such as coal ash discharged from glass bottles and thermal power plants can be used as a raw material for conductive vanadate glass, such as silicon, calcium, and sodium, to enable effective use of resources and to reduce the amount of waste. Reduces environmental protection.
(3) The glass skeleton can be formed under predetermined conditions, the electric conductivity can be improved by the electron hopping effect, the chemical durability can be improved by controlling the chemical potential of the glass surface, and the productivity can be controlled by controlling the melting temperature and glass transition temperature. There are advantages such as improvement of
(4) Since it is vitreous, structural changes due to intercalation such as generation of an intercalation compound can be reduced as compared with a crystalline material having a layered structure, and stable performance can be maintained.
(5) It is easy to form a thin film as compared with a crystalline material, and it is easy to form a film into a complicated shape and the like, and is excellent in workability. Application as is possible.
(6) Since a predetermined amount of vanadium, silicon, iron, calcium, sodium, etc., which is effective in adjusting electric conductivity and chemical durability, is contained, appropriateness in which both chemical durability and electric conductivity are balanced. State can be maintained.
(7) Since the conductive vanadate glass can be manufactured using inexpensive waste materials, it is economically excellent.
(8) A heat treatment condition is selected by using a correspondence relationship between heat treatment conditions such as a heat treatment temperature and a holding time and electric conductivity and chemical durability of the conductive vanadate glass obtained by the heat treatment condition. Since the characteristics can be arbitrarily adjusted, it is possible to manufacture an electrically conductive material having characteristics according to the application and the use environment.
[0042]
【The invention's effect】
According to the conductive vanadate glass of the first aspect, the following effects are obtained.
(1) Since the glass composition contains a predetermined amount of vanadium oxide, a glass skeleton excellent in electric conductivity and chemical durability can be formed. In this case, chemical durability as a protective coating material such as a lining for a chemical reaction vessel used in the above or an electrode material, a solid electrolyte, a sensor such as a thermistor can be maintained.
(2) Since the electric conductivity and the chemical durability are set within predetermined ranges, it is easy to design when applied to a protective coating, a thermistor, and an electrode element of a reaction vessel or the like exposed to an acid or an alkali, and the design is flexible. Excellent in nature.
(3) Since the glass composition can contain barium, iron, calcium, sodium and the like in addition to vanadium, the glass skeleton can be formed under a predetermined condition, and (1) the difference in ionic value is utilized. There are advantages such as improvement of electric conductivity by electron hopping effect, (2) improvement of chemical durability by controlling chemical potential of glass surface, and (3) improvement of productivity by controlling melting temperature and glass transition temperature.
(4) Since it is vitreous, structural changes due to intercalation such as generation of an intercalation compound can be reduced as compared with a crystalline material having a layered structure, and stable performance can be maintained.
(5) When applied to a cathode electrode for a secondary battery or the like, the electromotive force changes stepwise due to the presence of two phases in a crystalline material, but the electromotive force is almost constant in a vitreous material. Moreover, since the chemical diffusion coefficient can be increased, higher energy density can be obtained.
(6) Compared to crystalline ones, it can be easily formed into a thin film, can be reduced in size and weight, and is excellent in practicality, economy, functionality, and design.
(7) Since it is made of glass, it is easy to form a film into a complicated shape and the like, and it is excellent in workability, and can be used as a film forming material for various forms of semiconductor elements and reaction vessels.
[0043]
According to the conductive vanadate glass of the second aspect, the following effect is obtained in addition to the effect of the first aspect.
(1) Since the glass transition temperature is set in a specific low temperature range, when the conductive vanadate glass is applied to the lining of a reaction vessel for manufacturing pharmaceuticals, etc., the working temperature can be lowered, and the glass can be reduced. The lining can be easily installed, and the workability and economy are excellent.
(2) Since the glass transition temperature is specified in a predetermined range, when the conductive vanadate glass is subjected to an annealing treatment or the like, controllability of characteristics such as electric conductivity and chemical durability can be improved. In addition, it is possible to manufacture a semiconductor device or a sensor having small variations in quality and excellent reliability.
[0044]
According to the conductive vanadate glass of the third aspect, the following effects are obtained in addition to the effects of the first or second aspect.
(1) Since a certain amount of a vitrification adjusting component for adjusting a melting temperature or a glass transition temperature or constructing or modifying a glass skeleton during vitrification is contained, both chemical durability and electric conductivity are improved. Can be maintained in a proper state in which it is balanced, and is excellent in applicability as an anticorrosion coating material having electric conductivity.
(2) In particular, when calcium oxide, sodium oxide, silicon oxide, aluminum oxide, or the like is used as a vitrification adjusting component, glass cullet containing these components or coal ash from a power plant can be used. Industrial waste discharged in large quantities can be effectively used, and economical efficiency is achieved because inexpensive raw materials are used.
(3) The glass transition temperature and the chemical durability of the conductive vanadate glass can be effectively adjusted by adding a vitrification adjusting component including potassium oxide, barium oxide, boron oxide, strontium oxide, etc., thereby improving the chemical durability and electric power. A conductive vanadate glass having conductivity maintained in an appropriate state can be obtained, and a material excellent in controllability such as quality characteristics can be provided.
[0045]
According to the method for producing a conductive vanadate glass according to the fourth aspect, the following effects are obtained.
(1) Since it has a raw material adjustment step, it is possible to apply coal ash and the like discharged from a normally discarded glass bottle or a thermal power plant as a raw material to be a source of calcium, sodium, silicon, and aluminum of conductive vanadate glass. In addition, resources can be effectively used, and the amount of waste is reduced, resulting in excellent environmental protection.
(2) Since the conductive vanadate glass can be manufactured using inexpensive waste materials, it is excellent in economical efficiency.
(3) Since it has a heat treatment step of maintaining the mixture at a temperature equal to or higher than the glass transition temperature, it is possible to relax the structural distortion of the glass skeleton itself and to set properties such as electric conductivity and chemical durability within a predetermined range. Excellent in nature.
(4) Since the conductive vanadate glass is maintained at a heat treatment temperature equal to or higher than its glass transition temperature for a predetermined period of time, the distortion (strain) of the glass skeleton composed of vanadium, silicon, iron, aluminum, oxygen, etc. is reduced. Thus, the probability of electron hopping from vanadium tetravalent to pentavalent can be increased, the conductivity as a glass semiconductor or a protective film can be increased, and a long-life protective film, electrode, thermistor, and the like can be manufactured.
(5) A heat treatment condition is selected by using a correspondence relationship between heat treatment conditions such as a heat treatment temperature and a holding time and electric conductivity and chemical durability of the conductive vanadate glass obtained by the heat treatment condition. The characteristics can be arbitrarily adjusted, and a thermistor element, a conductive glass, or the like having characteristics according to the use or the use environment can be manufactured.

Claims (4)

It consists of a glass composition containing 0.1 to 25 mol% of vanadium oxide, has an electric conductivity of 10 ⁻⁸ to 10 ⁻⁴ S · cm ⁻¹ at room temperature, and elutes after immersion in 20% hydrochloric acid at room temperature for 72 hours. A conductive vanadate glass having an amount of 35% by mass or less. The conductive vanadate glass according to claim 1, wherein the glass transition temperature is 400 to 700 ° C. The glass composition contains 10 to 40 mol% of a vitrification adjusting component composed of any one of calcium oxide, sodium oxide, potassium oxide, barium oxide, boron oxide, and strontium oxide, or a combination of these components. The conductive vanadate glass according to claim 1 or 2, wherein The method for producing a conductive vanadate glass according to any one of claims 1 to 3, wherein a glass cullet or a combustion device obtained by crushing a glass bottle or the like into a vanadate composition containing vanadium, barium, or iron. A raw material adjustment step of mixing an alkali-containing composition such as coal ash discharged from coal, and a heat treatment step of melting the mixture and maintaining the mixture at a heat treatment temperature of a glass transition temperature or higher. Glass manufacturing method.