JP2004181342A

JP2004181342A - Oil removing treatment method for water soluble cutting oil and oil removing treatment system therefor

Info

Publication number: JP2004181342A
Application number: JP2002350883A
Authority: JP
Inventors: Hidehiko Okada; 秀彦岡田; Kenji Obara; 健司小原; Kazunari Mihashi; 和成三橋; Hitoshi Wada; 仁和田
Original assignee: Japan Science and Technology Agency; National Institute for Materials Science
Current assignee: Japan Science and Technology Agency; National Institute for Materials Science
Priority date: 2002-12-03
Filing date: 2002-12-03
Publication date: 2004-07-02

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil removing treatment method for removing a water soluble cutting oil, which is excellent in the treatment efficiency of a trapping material, traps a large amount of the water soluble cutting oil and is reused in the trapping of the water soluble cutting oil after the water soluble cutting oil is separated. <P>SOLUTION: The trapping material is used for removing the water soluble cutting oil from a liquid tank 1 in which the water soluble cutting oil is housed. The water soluble cutting oil in the liquid tank 1 is stirred by a stirring means 2 to be adsorbed by hydrophobic magnetic particles having a hydrophobic group on the surfaces thereof and the hydrophobic magnetic particles having adsorbed the water soluble cutting oil are magnetically caught by a catching means 3 to be removed from the liquid tank 1. The water soluble cutting oil adsorbed by the hydrophobic magnetic particles is separated in a separation tank 4 and the separated hydrophobic magnetic particles are extracted by an extraction means 5. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、使用済み等の水溶性切削油からその油を捕捉して分離する水溶性切削油の油除去処理方法及び水溶性切削油の油除去処理システムに関する。
【０００２】
【従来の技術】
近年、廃棄物処理として、工作機械などで使用される使用済みの水溶性切削油においても、その処理技術が開発され、特に、使用済みの水溶性切削油から油を除去して処理する技術が開発されている。
従来、このような使用済みの水溶性切削油からその油を除去する方法として、例えば特許文献１（特開平７−３０３８９４号公報）に記載された技術が知られている。
この特許文献１において、例えば、以下の技術が紹介されている。これは、水溶性切削油に無機あるいは有機系の凝集剤を添加して、排水中に溶解している水溶性切削油を凝集分離させるのに最適なｐＨ値領域に調整をおこない固液分離させ、さらに、分離液について濾過工程後、活性炭吸着といった高度処理をおこない放流水として排出させ、固液分離工程で発生するスラッジは産業廃棄物として場外に搬出させている。
【０００３】
また、特許文献１においては、このような処理法では、水溶性切削油を因とするＣＯＤ（化学的酸素要求量）及びｎ−ヘキサン抽出物質（油分）といった水質汚濁防止法に挙げられる項目についての除去が完全ではないことから、ｐＨ５．８〜８．６範囲内・常温・常圧に於いて、微生物を用い、排水中に含まれる水溶性切削油を活性汚泥法によって短時間に分解除去する方法が記載されている。
【０００４】
【特許文献１】
特開平７−３０３８９４号公報
【０００５】
【発明が解決しようとする課題】
ところで、上記従来の方法において、前者の有機系の凝集剤を添加する方法では、濾過工程後、活性炭吸着といった高度処理を行なうので、活性炭の処理を伴うことから処理効率が悪いという問題がある。活性炭で吸着させる度に、新たな活性炭を使用しなければならないことからその分無駄が生じているという問題もある。
また、後者の微生物を用いる方法では、微生物の繁殖のためのｐＨやエアレーション等の条件管理が容易ではなく、この方法でも処理効率が悪いという問題がある。
【０００６】
本発明は、このような問題点に鑑みてなされたもので、水溶性切削油の油を除去するための捕捉材の処理効率に優れ、水溶性切削油の油の大量捕捉が可能であり、水溶性切削油の油を分離して水溶性切削油の油の捕捉に再利用させることのできる水溶性切削油の油除去処理方法及び除去システムを提供することを目的とする。
【０００７】
【課題を解決するための手段】
このような課題を解決するための本発明の技術的手段は、水溶性切削油が入れられた液槽から当該水溶性切削油の油を除去する水溶性切削油の油除去処理方法において、表面に疎水性基を備えた疎水性磁性粒子に該水溶性切削油の油を吸着させ、該水溶性切削油の油が吸着した該疎水性磁性粒子を磁気的に捕捉して液槽から除去する構成とした。
ここで対象となる水溶性の切削油は、疎水性あるいは疎水性が強い油を含むものである。
【０００８】
これにより、疎水性磁性粒子を用いて水溶性切削油の油を疎水性相互作用により吸着させて、疎水性磁性粒子を磁気的に捕捉するので、水溶性切削油の油を疎水性磁性粒子とともに捕捉することができる。疎水性磁性粒子を、洗浄や分離膜を用いることなく磁気的に処理できるので疎水性磁性粒子の処理効率に優れる。水溶性切削油の油と疎水性磁性粒子とは疎水性相互作用により吸着されているので有機溶媒にて分離することが容易である。分離した疎水性磁性粒子は、水溶性切削油の油と吸着させることができるので、再利用が可能になる。
この結果、本発明は使用済みの水溶性切削油の処理に極めて有用になる。
【０００９】
また、必要に応じ、上記水溶性切削油の油が吸着した疎水性磁性粒子から該水溶性切削油の油を分離する構成とした。水溶性切削油の油が分離した疎水性磁性粒子は、再度水溶性切削油の油と吸着させるために利用することができる。
【００１０】
更に、必要に応じ、上記疎水性磁性粒子を上記水溶性切削油が入れられた上記液槽に投入する投入工程と、上記液槽中、上記疎水性磁性粒子と上記水溶性切削油の油とを吸着させる吸着工程と、上記液槽から上記疎水性磁性粒子に吸着した水溶性切削油の油を除去する除去工程と、上記した上記疎水性磁性粒子に吸着した水溶性切削油の油を分離する分離工程と、上記分離した上記疎水性磁性粒子を抽出する抽出工程とを備えた構成とした。
【００１１】
投入工程にて、水溶性切削油の油と疎水性磁性粒子とを液槽にいれる。吸着工程にて、液槽内の撹拌を行なう。撹拌を行なうことにより水溶性切削油の油と疎水性磁性粒子とは疎水性であることから水中にて凝集し易くなり吸着する。除去工程にて、撹拌した液槽内の溶液を、捕捉手段に供給し疎水性磁性粒子の磁気的捕捉を行なう。磁気フィルタに付着した疎水性磁性粒子は、逆洗されて回収される。分離工程にて回収された疎水性磁性粒子は、有機溶媒が入れられた分離槽に供給され水溶性切削油の油が吸着している疎水性磁性粒子からは水溶性切削油の油が分離して有機溶媒中に遊離する。抽出工程にて分離槽内に遊離している疎水性磁性粒子は、磁気的に捕捉することで分離槽内から回収される。回収した疎水性磁性粒子は、再度水溶性切削油の油の捕捉に用いることができる。
【００１２】
更にまた、必要に応じ、上記吸着工程を、上記疎水性磁性粒子と上記水溶性切削油の油とを接触可能に撹拌して行なう構成とした。撹拌することで、疎水性磁性粒子と水溶性切削油の油とが凝集し、疎水性相互作用を高め吸着し易くすることができる。
また、必要に応じ、上記分離工程を、上記水溶性切削油の油が吸着した疎水性磁性粒子を有機溶媒に混合して行なう構成とした。疎水性相互作用により吸着している水溶性切削油の油と疎水性磁性粒子とは有機溶媒にて容易に分離することができる。
更に、必要に応じ、上記抽出工程を、上記疎水性磁性粒子を磁気的に吸着して行なう構成とした。疎水性磁性粒子は磁石により集めることができ、抽出を容易に行なうことができる。
【００１３】
また、上記課題を解決するため、本発明の水溶性切削油の油除去処理システムは、水溶性切削油の油を除去する水溶性切削油の油除去処理システムにおいて、上記水溶性切削油が入れられるとともに表面に疎水性基を備えた疎水性磁性粒子が入れられた液槽と、該液槽中の混合液を上記水溶性切削油の油と上記疎水性磁性粒子とが吸着可能に撹拌する撹拌手段と、上記混合液から上記水溶性切削油の油が吸着した疎水性磁性粒子を捕捉する捕捉手段と、上記捕捉され上記水溶性切削油の油が吸着した疎水性磁性粒子から該水溶性切削油の油を分離する有機溶媒の分離槽と、上記分離槽で分離した疎水性磁性粒子を抽出する抽出手段とを備えて構成した。
【００１４】
そして、必要に応じ、上記捕捉手段を、磁化装置と該磁化装置で磁化されることにより上記疎水性磁性粒子を捕捉する磁気フィルタとを備えて構成した。
また、必要に応じ、上記抽出手段を、上記分離槽にて分離した疎水性磁性粒子を磁気的に抽出する磁気抽出部を備えて構成した。
【００１５】
【発明の実施の形態】
以下、添付図面に基づいて本発明の実施の形態に係る水溶性切削油の油除去処理方法及び除去処理システムを説明する。
図１及び図２は本発明の実施の形態に係る水溶性切削油の油除去処理方法が実現される水溶性切削油の油除去処理システムの図であり、図３は本発明の実施の形態に係る水溶性切削油の油除去処理方法の処理工程を示す図である。
【００１６】
先ず、水溶性切削油の油除去処理方法において、図４に示すように、水溶性切削油の油Ｈを除去するための捕捉材として用いる疎水性磁性粒子Ｐについて説明する。
疎水性磁性粒子Ｐは、磁性粒子Ｍの表面に疎水性基Ｗを備えたものであり、粒径１０ｎｍ以上、飽和磁化が０．０３Ｔ（テスラ）以上、比抵抗が１×１０^−９Ωｃｍ以上、ペレット成形時の水滴の接触角が１００度以上であるものが好ましい。
磁性粒子は、磁性金属微粒子，磁性金属酸化物微粒子または砂鉄のうち少なくとも１つを用いた。また、磁性粒子は、粒径１０ｎｍ〜１００ｎｍであることが好ましい。粒径１０ｎｍ〜１００ｎｍの場合には、磁気的に吸着させ易く、疎水性相互作用に関わる単位表面積が増加する。
【００１７】
磁性金属微粒子としては、Ｆｅ，Ｎｉ，Ｃｏ，Ｇｄ，Ｆｅ−Ｎｉ合金，Ｆｅ−Ｐｔ合金，Ｆｅ−Ｐｄ合金，Ｆｅ−Ｎｉ−Ｍｎ合金，Ｆｅ−Ｃｏ−Ｃｒ合金，Ｍｎ−Ａｌ合金，Ｍｎ−Ｚｎ合金，Ｍｎ−Ｇａ合金，Ｍｎ−Ｃｕ−Ａｌ合金，Ｆｅ_４Ｎ，Ｍｎ_３ＣｕＮ，Ｆｅ_３ＮｉＮ，Ｆｅ_３ＰｔＮ，Ｆｅ_２Ｎ_０．７５，Ｆｅ_２Ｎ，Ｆｅ_２Ｎ，Ｎｉ_３Ｎ_１．１０，ＣｄＣｒ_２Ｓ_４，ＣｄＣｒ_２Ｓｅ，Ａｇ_０．５Ｉｎ_０．５Ｃｒ_２Ｓｅ_４，ＨｇＣｒ_２Ｓ_４，ＣｕＣｒ_２Ｓｅ_３Ｂｒ，Ｃｕ_０．５Ｉｎ_０．５Ｃｒ_２Ｓｅ_４，ＥｕＢ_６，Ｅｕ_３Ｐ_３，Ｅｕ_３Ａｓ_２，ＭｎＡｓ，ＭｎＳｂ，ＭｎＢｉ，ＣｒＴｅ_４，ＮｉＭｎＳｂ，ＰｂＭｎＳｂ等が挙げられる。
【００１８】
磁性金属酸化物微粒子としては、α−ヘマタイト，γ−ヘマタイト，マグネタイト，ＭｎＦｅ_２Ｏ_４，ＣｏＦｅ_２Ｏ_４，ＣｕＦｅ_２Ｏ_４，ＭｇＦｅ_２Ｏ_４，ＺｕＦｅ_２Ｏ_４，ＬｉＦｅ_５Ｏ_８，Ｌｉ_０．５Ｆｅ_２．５Ｏ_４，Ｆｅ−Ｃｏフェライト，Ｓｍ−Ｃｏフェライト，Ｍｎ−Ｆｅフェライト，Ｍｎ−Ｚｎ−Ｆｅフェライト，Ｍｎ−Ｍｇ−Ｆｅフェライト，Ｎｉ−Ｚｕ−Ｆｅフェライト，Ｌｉ−Ｚｕ−Ｆｅフェライト，ＭｎＦｅ_２Ｏ_４ −ＭｎＣｒ_２Ｏ_４系，Ｆｅ_３Ｏ_４ −ＦｅＣｒ_２系，ＮｉＦｅ_２Ｏ_４ −ＮｉＣｒ_２Ｏ_４系，ＣｕＦｅ_２Ｏ_４ −ＣｕＣｒ_２Ｏ_４系，Ｌｉ_０．５Ｆｅ_２．５ −Ｌｉ_０．５Ｃｒ_２．５Ｏ_４系，マンガナイト，ＣａＦｅ_４Ｏ_７，Ｔｉ_２Ｏ_３，コランダム型磁性体，イルメナイト型磁性体，Ｍｎ−Ｃｒ−Ｓｂ系，Ｙ_３Ｆｅ_５Ｏ，ハイドロキシアパタイトセラミック，フルオロアパタイトセラミック等が挙げられる。
これら磁性金属微粒子，磁性金属酸化物微粒子は、強磁性体であることが好ましく、特にフェライト化法により合成したマグネタイトがより好ましい。磁気的に捕捉され易くなり、画一化した製法により容易に得ることができるからである。
【００１９】
疎水性基Ｗは、例えば、図５に示すように、炭素数３〜３０の直鎖アルキル基（図５（１）），炭素数３〜３０の芳香族炭化水素基，フェニル基，アルキルフェニル基（図５（２）），アゾベンゼン基，アルキルアゾベンゼン基（図５（３）），シアノ基，シクロデキストリン誘導体基，フラーレン誘導体基のうち少なくとも１つである。
【００２０】
疎水性基Ｗは、例えば、炭素数３〜３０の直鎖アルキル基，炭素数３〜３０の芳香族炭化水素基，フェニル基，アルキルフェニル基，アゾベンゼン基，アルキルアゾベンゼン基，シアノ基，シクロデキストリン誘導体基，フラーレン誘導体基のうち少なくとも１つからなるシランカップリング剤（例えば、図６参照），チタンカップリング剤またはジルコニウムカップリング剤を使用して磁性粒子の表面に化学吸着させた官能基である。カップリング剤は、物質に物質本来の性質と異なる性質を付与するための試薬であり、磁性粒子の表面に本来備わらない疎水性を付与する。
【００２１】
具体的には、ｎ−オクタデシルトリクロロシラン，ｎ−オクタデシルジクロロシラン，ｎ−オクタデシルジメトキシクロロシラン，ｎ−オクチルジクロロメトキシシラン，ｎ−オクチルジメトキシクロロシラン，ｎ−オクチルトリメトキシシラン，ｎ−オクチルトリエトキシシラン，ｎ−オクチルジエトキシクロロシラン，ｎ−オクチルジクロロエトキシシラン，ｎ−ブチルトリクロロシラン，ｎ−ブチルジクロロメトキシシラン，ｎ−ブチルジメトキシクロロシラン，ｎ−ブチルジエトキシクロロシラン，ｔｅｒｔ−ブチルトリクロロシラン，ｔｅｒｔ−ブチルジクロロメトキシシラン，ｔｅｒｔ−ブチルジメトキシクロロシラン，ｔｅｒｔ−ブチルジエトキシクロロシラン，ｎ−トリアコンチルトリクロロシラン，ｎ−トリアコンチルジクロロメトキシシラン，ｎ−トリアコンチルトリクロロメトキシシラン，ｎ−トリアコンチルジクロロメチルシラン，ｎ−トリアコンチルジメチルクロロシラン，フェニルトリクロロシラン，ジフェニルジクロロシラン，トリフェニルクロロシラン，フェニルトリエトキシシラン，ジフェニルジエトキシシラン，トリフェニルエトキシシラン，ｎ−オクタデシルジフェニルクロロシラン，ｎ−オクチルジフェニルクロロシラン，ｎ−ブチルジフェニルクロロシラン，ｎ−オクタデシルジフェニルメトキシシラン，ｎ−オクチルジフェニルメトキシシラン，ｎ−ブチルジフェニルメトキシシラン，シアノプロピルトリメトキシシラン，ｎ−（３−トリエトキシプロピル）−４−フェニルアゾベンアミド，４−オクチル−４’−ジクロロメチルシリルプロピル−アゾベンゼン，ジメチルクロロシリルフラーレン等が挙げられる。
【００２２】
次に、水溶性切削油の油除去処理方法について説明する。
ここで除去対象とする水溶性切削油は、疎水性もしくは疎水性が強い油を含むもので、例えば、図７に示すように、ＪＩＳＫ２２４１のＡ１種，Ａ２種として掲げられるものである。例えば、図４に示す直鎖型シリコーンオイルを含む水溶性切削油がある。
詳しくは、水溶性切削油はいくつかの種類に分類される。例えば、エマルジョン型水溶性切削油は、主に鉱物系，パラフィン系，ナフテン系の油と界面活性剤を混合したものであるが、動植物油を混合する場合もある。使用時は水で希釈（１０〜５０倍）し、乳白色の水中油形のエマルジョン化する。また、乳化剤（石油スルフォン酸塩、硫酸化油）カップリング剤を含む。長時間使用すると劣化し、油の分離，被削材に錆が生じたり、腐敗を起こすため、錆止め剤や殺菌剤も添加している。
また、セミケミカル型のソリュブル型半合成油は、合成切削油と乳化油を混合しエマルジョン型より油は少ないが界面活性剤が多いタイプである。これらが例として挙げられるがこれらに限定されるものではない。
【００２３】
本発明の実施の形態に係る水溶性切削油の油除去処理方法は、図１に示す水溶性切削油の油除去処理システムＳにおいて実現される。そのため、実施の形態に係る水溶性切削油の油除去処理方法は、水溶性切削油の油除去処理システムＳの作用において説明する。
【００２４】
水溶性切削油の油除去処理システムＳは、水溶性切削油を含む水溶液が入れられるとともに表面に疎水性基Ｗを備えた疎水性磁性粒子Ｐが入れられた液槽１と、液槽１中の混合液を水溶性切削油の油Ｈと疎水性磁性粒子Ｐとが吸着可能に撹拌する撹拌手段２と、混合液から水溶性切削油の油Ｈが吸着した疎水性磁性粒子Ｐを捕捉する捕捉手段３と、捕捉され水溶性切削油の油Ｈが吸着した疎水性磁性粒子Ｐから水溶性切削油の油Ｈを分離する有機溶媒が入れられた分離槽４と、分離槽４で分離した疎水性磁性粒子Ｐを抽出する抽出手段５とを備えて構成した。
【００２５】
液槽１は、例えば水溶性切削油の水溶液が収容される容器であればよく、特に限定されるものではない。
【００２６】
撹拌手段２は、特に限定されることなく水溶性切削油の油Ｈと疎水性磁性粒子Ｐを十分に混合することができるものであればよい。撹拌手段２には、液槽１内の溶液を回転させることができる棒状体を用いることができる。
【００２７】
捕捉手段３は、図２に示すように、液槽１と分離槽４との間の流路Ｘに設けられ、磁化装置６と磁化装置６で磁化されることにより疎水性磁性粒子Ｐを捕捉する磁気フィルタ７とを備えている。
【００２８】
磁化装置６は超伝導マグネットであり流路Ｘ内部に設けられた磁気フィルタ７の部分の流路Ｘ外部を覆うように設置している。
磁気フィルタ７は、磁性細線Ｌからなる多層メッシュで形成され磁化装置６により生じた磁場により生じる磁力線に対して磁性細線Ｌが直角になるように配置される（図２（２）参照）。従って、磁化の際に磁性細線Ｌの表面近傍に磁気勾配が生じる。
磁性細線Ｌは、付着する磁化物質の物理量に応じて付着し易い大きさ（直径）であればよい。磁性細線Ｌの材質としては、磁化されるものであればよいが必要に応じて消磁化できる軟磁性材料の強磁性体が好ましい。
【００２９】
捕捉手段３では、捕捉した疎水性磁性粒子Ｐを回収する逆洗処理も行なう。逆洗処理では、疎水性磁性粒子Ｐが付着した磁気フィルタ７を消磁化して水で洗浄して磁気フィルタ７に付着した疎水性磁性粒子Ｐを除去している。
【００３０】
分離槽４は、水溶性切削油の油Ｈが吸着した疎水性磁性粒子Ｐから水溶性切削油の油Ｈを分離することができる有機溶媒が入れられる容器であればよい。有機溶媒としては、アセトニトリル，メチルアルコール，エチルアルコール，アセトン等が挙げられる。
【００３１】
抽出手段５は、分離槽４にて分離した疎水性磁性粒子Ｐを磁気的に抽出する磁気抽出部を備えて構成した。磁気抽出部は、分離槽４に接続し超伝導マグネットを用いて固液分離を行ない疎水性磁性粒子Ｐを吸着するようにしている。
【００３２】
従って、本発明の水溶性切削油の油除去処理システムＳによれば、図３に示す処理工程に従って、疎水性磁性粒子Ｐを用いて例えば使用済みの水溶性切削油の油Ｈを除去することができ、かつ用いた疎水性磁性粒子Ｐを再利用可能にする。
【００３３】
（投入工程）
水溶性切削油が溶解した水溶液の入った液槽１に疎水性磁性粒子Ｐを投入する。
【００３４】
（吸着工程）
液槽１内の撹拌を行なう。撹拌を行なうことにより水溶性切削油の油Ｈと疎水性磁性粒子Ｐとは疎水性であることから水中にて凝集し易くなり疎水性相互作用により吸着する。
図４に示すように、疎水性磁性粒子Ｐの表面にカップリング剤により化学吸着している疎水性基Ｗ（例えば、オクタデシル基）には、水溶性切削油の油Ｈが疎水性相互作用する。疎水性磁性粒子Ｐと水溶性切削油の油Ｈとは、疎水性相互作用により吸着が行なわれる。
【００３５】
（除去工程）
撹拌した液槽１内の溶液を、捕捉手段３に供給し疎水性磁性粒子Ｐの磁気的捕捉を行なう。磁気的捕捉は、磁化された磁気フィルタ７に液槽１内の溶液を供給することにより磁化されている疎水性磁性粒子Ｐが磁気フィルタ７に付着することにより行なわれる。磁気フィルタ７に付着した疎水性磁性粒子Ｐは、逆洗されて回収される。
【００３６】
（分離工程）
回収された疎水性磁性粒子Ｐは、有機溶媒が入れられた分離槽４に供給され水溶性切削油の油Ｈが吸着している疎水性磁性粒子Ｐからは水溶性切削油の油Ｈが分離して有機溶媒中に遊離する。水溶性切削油の油Ｈは、溶解度のより高い有機溶媒に溶けるので、有機溶媒の介在により疎水性磁性粒子Ｐより脱離されるためである。
【００３７】
（抽出工程）
分離槽４内に遊離している疎水性磁性粒子Ｐは、磁気的に捕捉することで分離槽４内から回収される。回収された疎水性磁性粒子Ｐは、再度水溶性切削油の油Ｈの捕捉に用いることができる。
【００３８】
以下、本発明の水溶性切削油の油除去処理方法の実施例について説明する。
［実施例１］
（疎水性磁性粒子Ｐの調製）
０．５モルの硫酸鉄（ＩＩ）水和物と０．５モルの硫酸鉄（ＩＩＩ）水和物を夫々６０℃の水５００ｍｌに溶解させた後混合して混合溶液にした。
次いで、得られた混合溶液に６ｍｏｌ／Ｌの水酸化ナトリウムをｐＨが１１になるまで加えた後、６０℃で１時間撹拌しマグネタイトが合成された混濁液を得た。
この混濁液を磁石を用いてデカンデーションした。デカンデーションは、塩分を除去するために上澄み液のｐＨが７になるまで繰り返した。
次いで、脱水するために、上澄み液を極力取り除き６０℃で１週間乾燥後更に減圧法にて２４時間乾燥して、目的とするマグネタイトを得た。
マグネタイトの表面処理のため、等圧滴下漏斗に脱水トルエン５０ｍｌをとり５ｍｌのｎ−オクタデシルトリクロロシランを添加した。次いで、三口フラスコに乾燥済のマグネタイト５ｇ及び５ｍｌのトリエチルアミンを添加して窒素雰囲気下で４８時間撹拌した。
図７には、マグネタイトにシランカップリング剤であるｎ−オクタデシルトリクロロシランを処理させた場合の反応状態が示される。
マグネタイトとｎ−オクタデシルトリクロロシランとをトリエチルアミン及び脱水トルエン中で反応させることによりｎ−オクタデシルトリクロロシラン化マグネタイトが得られる。
得られた溶液を、遠心分離してデカンデーションにて数回トルエンで洗浄後、テトラヒドロフラン、メタノールで順次洗浄した。
最後に、アセトンで洗浄後、上澄み液を極力取り除き減圧乾燥して疎水性磁性粒子Ｐを得た。
【００３９】
（疎水性磁性粒子Ｐの評価）
得られた疎水性磁性粒子Ｐを加重２５００Ｎ／ｃｍ^２でペレットにし、表面に水滴を滴下して疎水性の評価を行なった。ペレットへの吸収は全くなく水滴は球になって撥水性を示した。
比較例として、上記マグネタイト（表面処理を施していないもの）を用いてペレットを形成したものを用いた。これについて、同様に疎水性の評価を行なうと、水滴は球にならずペレット表面にしみ込みペレット内部を通過するのみで、撥水性は認められなかった。
以上から、疎水性磁性粒子Ｐの表面が疎水性を有していることが明らかであることを確認できた。
【００４０】
（水溶性切削油の油Ｈの除去）
得られた２ｇの疎水性磁性粒子Ｐを、２０ｍｌの２倍に希釈した使用済み水溶性切削油水溶液に添加した。添加後、十分に撹拌すると白濁していた使用済み切削油水溶液が透明になった。従って、疎水性磁性粒子Ｐに使用済み水溶性切削油が吸着し処理水を浄化することができた。
【００４１】
（水溶性切削油の油Ｈの分離）
処理液を磁気分離し上澄み液を取り除いた。残った沈殿物にメタノールを１０ｍｌ添加しよく撹拌した。撹拌後、溶液の臭いが切削油の臭いになっていた。従って、疎水性磁性粒子Ｐより吸着した使用済み水溶性切削油およびその腐敗物を抽出することができ、疎水性磁性粒子Ｐ表面を洗浄することができた。使用後に洗浄した上記の疎水性磁性粒子Ｐを用い、再び２倍に希釈した使用済み水溶性切削油水溶液に添加・撹拌した。処理済み溶液は、白濁から透明になり浄化できた。従って、再利用可能であることがわかる。
【００４２】
［実施例２］
磁性粒子に砂鉄を用い、砂鉄の表面処理のため、等圧滴下漏斗に脱水トルエン５０ｍｌをとり５ｍｌのｎ−オクタデシルトリクロロシランを添加した。次いで、三口フラスコに乾燥済のマグネタイト５ｇ及び５ｍｌのトリエチルアミンを添加して窒素雰囲気下で４８時間撹拌した。
得られた溶液を、遠心分離してデカンデーションにて数回トルエンで洗浄後、テトラヒドロフラン、メタノールで順次洗浄した。
最後に、アセトンで洗浄後、上澄み液を極力取り除き減圧乾燥して疎水性磁性粒子Ｐを得た。
【００４３】
（疎水性磁性粒子Ｐの評価）
実施例１と同様にペレットを形成して、疎水性の試験を行なった結果実施例１と同様の効果が得られた。
【００４４】
【発明の効果】
以上説明したように、本発明の水溶性切削油の油除去処理方法及び除去処理システムによれば、表面に疎水性基を備えた疎水性磁性粒子に水溶性切削油の油を吸着させ、水溶性切削油の油が吸着した疎水性磁性粒子を磁気的に捕捉して液槽から除去する構成としたので、疎水性磁性粒子を用いて水溶性切削油の油を疎水性相互作用により吸着させて、疎水性磁性粒子を磁気的に捕捉することができ、水溶性切削油の油を疎水性磁性粒子とともに捕捉することができる。捕捉した疎水性磁性粒子は、洗浄や分離膜により除去することなく磁気的に除去できるので処理効率に優れている。また、水溶性切削油の油と疎水性磁性粒子とは疎水性相互作用により吸着されているので有機溶媒にて分離させることを容易にすることができる。この結果、本発明は使用済みの水溶性切削油の処理に極めて有用になる。
【００４５】
また、水溶性切削油の油が吸着した疎水性磁性粒子から水溶性切削油の油を分離する構成とした場合には、分離した疎水性磁性粒子を水溶性切削油の油と吸着させるために再利用させることができる。
更に、疎水性磁性粒子を水溶性切削油が入れられた液槽に投入する投入工程と、水溶性切削油の油含有水中、疎水性磁性粒子と水溶性切削油の油とを吸着させる吸着工程と、液槽から疎水性磁性粒子に吸着した水溶性切削油の油を除去する除去工程と、疎水性磁性粒子に吸着した水溶性切削油の油から水溶性切削油の油を分離する分離工程と、分離した上記疎水性磁性粒子を抽出する抽出工程とを備えた構成とした場合には、水溶性切削油の油の捕捉処理、疎水性磁性粒子からの水溶性切削油の油の分離処理及び疎水性磁性粒子を再利用するための抽出処理を効率良く行なうことができる。
【００４６】
更にまた、吸着工程を、疎水性磁性粒子と水溶性切削油の油とを接触可能に撹拌して行なう構成とした場合には、撹拌という容易な操作ですることで疎水性磁性粒子と水溶性切削油の油とを凝集させ、疎水性相互作用により吸着し易くすることができる。
また、分離工程を、水溶性切削油の油が吸着した疎水性磁性粒子を有機溶媒に混合して行なう構成とした場合には、疎水性相互作用により吸着している水溶性切削油の油と疎水性磁性粒子とは有機溶媒にて容易に分離することができる。
更に、抽出工程を、疎水性磁性粒子を磁気的に吸着して行なう構成とした場合には、磁石で疎水性磁性粒子を集めて再利用させることができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る水溶性切削油の油除去処理方法が実現される水溶性切削油の油除去処理システムの図である。
【図２】本発明の実施の形態に係る水溶性切削油の油除去処理方法が実現される水溶性切削油の油除去処理システムの捕捉手段を示し、（１）は捕捉手段の構成を示す図であり、（２）は磁気フィルタを示す図である。
【図３】本発明の実施の形態に係る水溶性切削油の油除去処理方法の処理工程を示す図である。
【図４】本発明の実施の形態に係る水溶性切削油の油除去処理方法における水溶性切削油の油の捕捉状態を示す図である。
【図５】本発明の実施の形態に係る水溶性切削油の油除去処理方法で用いる疎水性磁性粒子の疎水性基を示す図である。
【図６】水溶性切削油の規格例を示す図である。
【図７】本発明の実施例における疎水性磁性粒子の調製例を示す図である。
【符号の説明】
Ｓ水溶性切削油の油除去処理システム
Ｐ疎水性磁性粒子
Ｍ磁性粒子
Ｗ疎水性基
Ｈ水溶性切削油の油
１液槽
２撹拌手段
３捕捉手段
４分離槽
５抽出手段
６磁化装置
７磁気フィルタ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a water-soluble cutting oil removal method and a water-soluble cutting oil removal treatment system that captures and separates water-soluble cutting oil from used water.
[0002]
[Prior art]
In recent years, as a waste treatment, a processing technology has been developed for used water-soluble cutting oil used in machine tools and the like. In particular, a technology for removing oil from used water-soluble cutting oil and treating it has been developed. Is being developed.
Conventionally, as a method of removing such used water-soluble cutting oil from the used water-soluble cutting oil, for example, a technique described in Patent Document 1 (Japanese Patent Application Laid-Open No. 7-303894) is known.
In this Patent Document 1, for example, the following technology is introduced. This is achieved by adding an inorganic or organic coagulant to the water-soluble cutting oil, adjusting the pH value to the optimal pH range for coagulating and separating the water-soluble cutting oil dissolved in the wastewater, and performing solid-liquid separation. Further, after the filtration step, the separated liquid is subjected to advanced treatment such as activated carbon adsorption and discharged as effluent, and sludge generated in the solid-liquid separation step is carried out as industrial waste outside the plant.
[0003]
Further, in Patent Document 1, in such a treatment method, items listed in the water pollution prevention method such as COD (chemical oxygen demand) and n-hexane extractable substance (oil component) due to water-soluble cutting oil are described. Because of the incomplete removal of water, the water-soluble cutting oil contained in the wastewater is decomposed and removed in a short time by activated sludge using microorganisms at pH 5.8 to 8.6, at normal temperature and normal pressure. A method is described.
[0004]
[Patent Document 1]
JP-A-7-303894
[0005]
[Problems to be solved by the invention]
By the way, in the above-mentioned conventional method, in the former method of adding an organic coagulant, there is a problem that the treatment efficiency is low because the treatment of the activated carbon is performed after the filtration step because the treatment involves the advanced treatment such as the adsorption of the activated carbon. There is also a problem that a new activated carbon has to be used every time adsorption is performed with activated carbon, so that waste is generated.
Further, in the latter method using microorganisms, it is not easy to control conditions such as pH and aeration for propagation of microorganisms, and there is a problem that this method also has poor treatment efficiency.
[0006]
The present invention has been made in view of such problems, is excellent in the processing efficiency of the trapping material for removing the oil of the water-soluble cutting oil, it is possible to capture a large amount of oil of the water-soluble cutting oil, An object of the present invention is to provide a method and system for removing oil from a water-soluble cutting oil, which can separate the oil of the water-soluble cutting oil and reuse the oil for capturing the oil of the water-soluble cutting oil.
[0007]
[Means for Solving the Problems]
The technical means of the present invention for solving such a problem is an oil removal treatment method for a water-soluble cutting oil, which removes the oil of the water-soluble cutting oil from a liquid tank containing the water-soluble cutting oil. The oil of the water-soluble cutting oil is adsorbed on the hydrophobic magnetic particles having a hydrophobic group, and the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed are magnetically captured and removed from the liquid tank. Configuration.
Here, the target water-soluble cutting oil includes oil having hydrophobicity or strong hydrophobicity.
[0008]
As a result, the oil of the water-soluble cutting oil is adsorbed by the hydrophobic interaction using the hydrophobic magnetic particles, and the hydrophobic magnetic particles are magnetically captured. Can be captured. Since the hydrophobic magnetic particles can be magnetically processed without using a washing or separation membrane, the processing efficiency of the hydrophobic magnetic particles is excellent. Since the oil of the water-soluble cutting oil and the hydrophobic magnetic particles are adsorbed by hydrophobic interaction, they can be easily separated with an organic solvent. The separated hydrophobic magnetic particles can be adsorbed with the water-soluble cutting oil, so that they can be reused.
As a result, the present invention is extremely useful for treating used water-soluble cutting oil.
[0009]
Further, if necessary, the oil of the water-soluble cutting oil is separated from the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed. The hydrophobic magnetic particles from which the oil of the water-soluble cutting oil has been separated can be used again to adsorb the oil of the water-soluble cutting oil.
[0010]
Further, if necessary, a charging step of charging the hydrophobic magnetic particles into the liquid tank containing the water-soluble cutting oil, and in the liquid tank, the hydrophobic magnetic particles and the oil of the water-soluble cutting oil. An adsorbing step of adsorbing water, a removing step of removing water-soluble cutting oil adsorbed on the hydrophobic magnetic particles from the liquid tank, and separating the water-soluble cutting oil adsorbed on the hydrophobic magnetic particles. And an extraction step of extracting the separated hydrophobic magnetic particles.
[0011]
In the charging step, the oil of the water-soluble cutting oil and the hydrophobic magnetic particles are put into a liquid tank. In the adsorption step, stirring in the liquid tank is performed. By agitation, the oil of the water-soluble cutting oil and the hydrophobic magnetic particles are hydrophobic and easily aggregate and adsorb in water. In the removing step, the solution in the stirred liquid tank is supplied to a capturing means to magnetically capture the hydrophobic magnetic particles. The hydrophobic magnetic particles attached to the magnetic filter are backwashed and collected. The hydrophobic magnetic particles collected in the separation step are supplied to a separation tank containing an organic solvent, and water-soluble cutting oil is separated from the hydrophobic magnetic particles to which the water-soluble cutting oil is adsorbed. To be released in organic solvents. The hydrophobic magnetic particles released in the separation tank in the extraction step are collected from the separation tank by being magnetically captured. The collected hydrophobic magnetic particles can be used again for capturing the oil of the water-soluble cutting oil.
[0012]
Further, if necessary, the adsorption step is performed by stirring the hydrophobic magnetic particles and the oil of the water-soluble cutting oil so as to be in contact with each other. By stirring, the hydrophobic magnetic particles and the oil of the water-soluble cutting oil are aggregated, and the hydrophobic interaction can be enhanced to facilitate the adsorption.
Further, if necessary, the separation step is performed by mixing hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed with an organic solvent. The oil of the water-soluble cutting oil adsorbed by the hydrophobic interaction and the hydrophobic magnetic particles can be easily separated with an organic solvent.
Further, if necessary, the extraction step is performed by magnetically adsorbing the hydrophobic magnetic particles. The hydrophobic magnetic particles can be collected by a magnet and can be easily extracted.
[0013]
Further, in order to solve the above-mentioned problem, an oil removal treatment system for a water-soluble cutting oil according to the present invention is an oil removal treatment system for a water-soluble cutting oil for removing oil of a water-soluble cutting oil, wherein the water-soluble cutting oil is added. And a liquid tank containing hydrophobic magnetic particles having a hydrophobic group on its surface, and a mixture in the liquid tank is stirred so that the oil of the water-soluble cutting oil and the hydrophobic magnetic particles can be adsorbed. Agitating means, capturing means for capturing the hydrophobic magnetic particles to which the water-soluble cutting oil oil is adsorbed from the liquid mixture, and water-soluble from the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed. The apparatus was provided with an organic solvent separation tank for separating the oil of the cutting oil, and extraction means for extracting the hydrophobic magnetic particles separated in the separation tank.
[0014]
If necessary, the capturing means is provided with a magnetizing device and a magnetic filter that captures the hydrophobic magnetic particles by being magnetized by the magnetizing device.
Further, if necessary, the extraction means is provided with a magnetic extraction unit for magnetically extracting the hydrophobic magnetic particles separated in the separation tank.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an oil removal treatment method and a removal treatment system for a water-soluble cutting oil according to an embodiment of the present invention will be described with reference to the accompanying drawings.
1 and 2 are diagrams of a water-soluble cutting oil oil removal treatment system that realizes a water-soluble cutting oil oil removal treatment method according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. It is a figure which shows the processing process of the oil removal processing method of water-soluble cutting oil concerning this.
[0016]
First, in the method of removing oil from water-soluble cutting oil, hydrophobic magnetic particles P used as a trapping material for removing oil H from water-soluble cutting oil will be described with reference to FIG.
The hydrophobic magnetic particles P are provided with hydrophobic groups W on the surface of the magnetic particles M, and have a particle diameter of 10 nm or more, a saturation magnetization of 0.03 T (tesla) or more, and a specific resistance of 1 × 10 ^-9 It is preferable that the contact angle of a water droplet at the time of forming a pellet is 100 degrees or more.
As the magnetic particles, at least one of magnetic metal fine particles, magnetic metal oxide fine particles, and iron sand was used. The magnetic particles preferably have a particle size of 10 nm to 100 nm. When the particle size is 10 nm to 100 nm, the magnetic particles are easily magnetically adsorbed, and the unit surface area related to the hydrophobic interaction increases.
[0017]
Examples of the magnetic metal fine particles include Fe, Ni, Co, Gd, Fe-Ni alloy, Fe-Pt alloy, Fe-Pd alloy, Fe-Ni-Mn alloy, Fe-Co-Cr alloy, Mn-Al alloy, Mn- Zn alloy, Mn-Ga alloy, Mn-Cu-Al alloy, Fe ₄ N, Mn ₃ CuN, Fe ₃ NiN, Fe ₃ PtN, Fe ₂ N _0.75 , Fe ₂ N, Fe ₂ N, Ni ₃ N _1.10 , CdCr ₂ S ₄ , CdCr ₂ Se, Ag _0.5 In _0.5 Cr ₂ Se ₄ , HgCr ₂ S ₄ , CuCr ₂ Se ₃ Br, Cu _0.5 In _0.5 Cr ₂ Se ₄ , EuB ₆ , Eu ₃ P ₃ , Eu ₃ As ₂ , MnAs, MnSb, MnBi, CrTe ₄ , NiMnSb, PbMnSb, and the like.
[0018]
As the magnetic metal oxide fine particles, α-hematite, γ-hematite, magnetite, MnFe ₂ O ₄ , CoFe ₂ O ₄ , CuFe ₂ O ₄ , MgFe ₂ O ₄ , ZuFe ₂ O ₄ , LiFe ₅ O ₈ , Li _0.5 Fe _2.5 O ₄ , Fe-Co ferrite, Sm-Co ferrite, Mn-Fe ferrite, Mn-Zn-Fe ferrite, Mn-Mg-Fe ferrite, Ni-Zu-Fe ferrite, Li-Zu-Fe ferrite, MnFe ₂ O ₄ -MnCr ₂ O ₄ System, Fe ₃ O ₄ -FeCr ₂ System, NiFe ₂ O ₄ -NiCr ₂ O ₄ System, CuFe ₂ O ₄ -CuCr ₂ O ₄ System, Li _0.5 Fe _2.5 −Li _0.5 Cr _2.5 O ₄ System, manga night, CaFe ₄ O ₇ , Ti ₂ O ₃ , Corundum type magnetic material, ilmenite type magnetic material, Mn-Cr-Sb system, Y ₃ Fe ₅ O, hydroxyapatite ceramic, fluoroapatite ceramic, and the like.
These magnetic metal fine particles and magnetic metal oxide fine particles are preferably ferromagnetic substances, and more preferably magnetite synthesized by a ferrite method. This is because it is easily magnetically captured and can be easily obtained by a uniform manufacturing method.
[0019]
As shown in FIG. 5, the hydrophobic group W is, for example, a linear alkyl group having 3 to 30 carbon atoms (FIG. 5A), an aromatic hydrocarbon group having 3 to 30 carbon atoms, a phenyl group, an alkylphenyl group. Group (FIG. 5 (2)), azobenzene group, alkylazobenzene group (FIG. 5 (3)), cyano group, cyclodextrin derivative group, and fullerene derivative group.
[0020]
The hydrophobic group W is, for example, a linear alkyl group having 3 to 30 carbon atoms, an aromatic hydrocarbon group having 3 to 30 carbon atoms, a phenyl group, an alkylphenyl group, an azobenzene group, an alkylazobenzene group, a cyano group, a cyclodextrin. A functional group chemically adsorbed on the surface of magnetic particles using a silane coupling agent (for example, see FIG. 6), a titanium coupling agent, or a zirconium coupling agent comprising at least one of a derivative group and a fullerene derivative group. is there. The coupling agent is a reagent for imparting a property different from the intrinsic property of the substance to the substance, and imparts a hydrophobic property not originally provided to the surface of the magnetic particle.
[0021]
Specifically, n-octadecyltrichlorosilane, n-octadecyldichlorosilane, n-octadecyldimethoxychlorosilane, n-octyldichloromethoxysilane, n-octyldimethoxychlorosilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-octyldiethoxychlorosilane, n-octyldichloroethoxysilane, n-butyltrichlorosilane, n-butyldichloromethoxysilane, n-butyldimethoxychlorosilane, n-butyldiethoxychlorosilane, tert-butyltrichlorosilane, tert-butyldichloro Methoxysilane, tert-butyldimethoxychlorosilane, tert-butyldiethoxychlorosilane, n-triacontyltrichlorosilane, n-triacontyldi Loromethoxysilane, n-triacontyltrichloromethoxysilane, n-triacontyldichloromethylsilane, n-triacontyldimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, triphenylchlorosilane, phenyltriethoxysilane, diphenyldiethoxy Silane, triphenylethoxysilane, n-octadecyldiphenylchlorosilane, n-octyldiphenylchlorosilane, n-butyldiphenylchlorosilane, n-octadecyldiphenylmethoxysilane, n-octyldiphenylmethoxysilane, n-butyldiphenylmethoxysilane, cyanopropyltrimethoxy Silane, n- (3-triethoxypropyl) -4-phenylazobenamide, 4-octyl-4'-dichloromethylsilyl Propyl - azobenzene, dimethylchlorosilyl fullerene, and the like.
[0022]
Next, an oil removal treatment method for the water-soluble cutting oil will be described.
The water-soluble cutting oil to be removed here contains oil having a high hydrophobicity or hydrophobicity. For example, as shown in FIG. 7, the oils are listed as A1 and A2 in JIS K2241. For example, there is a water-soluble cutting oil containing a linear silicone oil shown in FIG.
Specifically, water-soluble cutting oils are classified into several types. For example, the emulsion type water-soluble cutting oil is mainly a mixture of a mineral, paraffin, or naphthenic oil and a surfactant, but may be a mixture of animal and vegetable oils. When used, it is diluted with water (10- to 50-fold) to form a milky white oil-in-water emulsion. It also contains an emulsifier (petroleum sulfonate, sulfated oil) coupling agent. It deteriorates when used for a long time, causes oil separation, causes rust on the work material, and causes decay. Therefore, a rust inhibitor and a disinfectant are also added.
Further, the semi-chemical type soluble semi-synthetic oil is a type in which a synthetic cutting oil and an emulsified oil are mixed and the amount of the surfactant is larger than that of the emulsion type. These are given as examples, but not limited thereto.
[0023]
An oil removal processing method for a water-soluble cutting oil according to an embodiment of the present invention is realized in an oil removal processing system S for a water-soluble cutting oil shown in FIG. Therefore, the oil-removal processing method for water-soluble cutting oil according to the embodiment will be described in the operation of the oil-removal processing system S for water-soluble cutting oil.
[0024]
The oil removal treatment system S for a water-soluble cutting oil includes a liquid tank 1 in which an aqueous solution containing a water-soluble cutting oil is put and hydrophobic magnetic particles P having a hydrophobic group W on its surface are put. A stirring means 2 for stirring the mixed solution of the water-soluble cutting oil oil H and the hydrophobic magnetic particles P so that the oil H and the hydrophobic magnetic particles P can be adsorbed, and trapping the hydrophobic magnetic particles P to which the water-soluble cutting oil oil H is adsorbed from the mixed solution. The separation means 4 separates the trapping means 3, a separation tank 4 containing an organic solvent for separating the water-soluble cutting oil H from the hydrophobic magnetic particles P to which the water-soluble cutting oil H is adsorbed. Extraction means 5 for extracting the hydrophobic magnetic particles P is provided.
[0025]
The liquid tank 1 is not particularly limited as long as it is a container that stores, for example, an aqueous solution of a water-soluble cutting oil.
[0026]
The stirring means 2 is not particularly limited as long as it can sufficiently mix the oil H of the water-soluble cutting oil and the hydrophobic magnetic particles P. As the stirring means 2, a rod-like body capable of rotating the solution in the liquid tank 1 can be used.
[0027]
As shown in FIG. 2, the capturing means 3 is provided in a flow path X between the liquid tank 1 and the separation tank 4, and captures the hydrophobic magnetic particles P by being magnetized by the magnetizing device 6 and the magnetizing device 6. And a magnetic filter 7.
[0028]
The magnetizing device 6 is a superconducting magnet and is installed so as to cover the outside of the flow path X at a portion of the magnetic filter 7 provided inside the flow path X.
The magnetic filter 7 is formed of a multilayer mesh composed of the magnetic thin wires L, and is arranged such that the magnetic thin wires L are perpendicular to magnetic lines of force generated by the magnetic field generated by the magnetizing device 6 (see FIG. 2 (2)). Therefore, a magnetic gradient is generated near the surface of the magnetic wire L during magnetization.
The magnetic fine wire L may have a size (diameter) that can be easily attached according to the physical quantity of the attached magnetic substance. The material of the magnetic wire L may be any material as long as it can be magnetized, but a ferromagnetic material of a soft magnetic material that can be demagnetized as necessary is preferable.
[0029]
The capturing means 3 also performs a backwashing process for recovering the captured hydrophobic magnetic particles P. In the backwashing process, the magnetic filter 7 to which the hydrophobic magnetic particles P are attached is demagnetized and washed with water to remove the hydrophobic magnetic particles P attached to the magnetic filter 7.
[0030]
The separation tank 4 may be a container in which an organic solvent capable of separating the water-soluble cutting oil H from the hydrophobic magnetic particles P to which the water-soluble cutting oil H is adsorbed is put. Examples of the organic solvent include acetonitrile, methyl alcohol, ethyl alcohol, acetone and the like.
[0031]
The extraction means 5 was provided with a magnetic extraction part for magnetically extracting the hydrophobic magnetic particles P separated in the separation tank 4. The magnetic extraction unit is connected to the separation tank 4 and performs solid-liquid separation using a superconducting magnet to adsorb the hydrophobic magnetic particles P.
[0032]
Therefore, according to the water-soluble cutting oil removal processing system S of the present invention, for example, the used water-soluble cutting oil oil H is removed using the hydrophobic magnetic particles P according to the processing steps shown in FIG. And the used hydrophobic magnetic particles P can be reused.
[0033]
(Input process)
The hydrophobic magnetic particles P are charged into a liquid tank 1 containing an aqueous solution in which a water-soluble cutting oil is dissolved.
[0034]
(Adsorption process)
The liquid tank 1 is stirred. By performing the stirring, the oil H of the water-soluble cutting oil and the hydrophobic magnetic particles P are hydrophobic, so that they are easily aggregated in water and adsorbed by hydrophobic interaction.
As shown in FIG. 4, a water-soluble cutting oil H interacts with a hydrophobic group W (for example, an octadecyl group) chemically adsorbed on the surface of the hydrophobic magnetic particles P by a coupling agent. . The hydrophobic magnetic particles P and the water-soluble cutting oil H are adsorbed by hydrophobic interaction.
[0035]
(Removal process)
The solution in the stirred liquid tank 1 is supplied to the capturing means 3 to magnetically capture the hydrophobic magnetic particles P. The magnetic capture is performed by supplying the solution in the liquid tank 1 to the magnetized magnetic filter 7 so that the magnetized hydrophobic magnetic particles P adhere to the magnetic filter 7. The hydrophobic magnetic particles P attached to the magnetic filter 7 are backwashed and collected.
[0036]
(Separation process)
The collected hydrophobic magnetic particles P are supplied to a separation tank 4 containing an organic solvent, and water-soluble cutting oil H is separated from the hydrophobic magnetic particles P on which the water-soluble cutting oil H is adsorbed. To be released in an organic solvent. This is because the oil H of the water-soluble cutting oil is dissolved in the organic solvent having a higher solubility, and thus is desorbed from the hydrophobic magnetic particles P by the interposition of the organic solvent.
[0037]
(Extraction process)
The hydrophobic magnetic particles P released in the separation tank 4 are collected from the separation tank 4 by being magnetically captured. The collected hydrophobic magnetic particles P can be used again for capturing the oil H of the water-soluble cutting oil.
[0038]
Hereinafter, an example of the oil removal treatment method of the water-soluble cutting oil of the present invention will be described.
[Example 1]
(Preparation of hydrophobic magnetic particles P)
0.5 mol of iron (II) sulfate hydrate and 0.5 mol of iron (III) sulfate hydrate were each dissolved in 500 ml of water at 60 ° C. and mixed to form a mixed solution.
Next, 6 mol / L sodium hydroxide was added to the obtained mixed solution until the pH reached 11, and the mixture was stirred at 60 ° C. for 1 hour to obtain a turbid liquid in which magnetite was synthesized.
This turbid liquid was decanted using a magnet. The decantation was repeated until the pH of the supernatant was 7 to remove the salt.
Next, for dehydration, the supernatant liquid was removed as much as possible and dried at 60 ° C. for 1 week, followed by drying under reduced pressure for 24 hours to obtain the desired magnetite.
For surface treatment of magnetite, 50 ml of dehydrated toluene was placed in a constant-pressure dropping funnel, and 5 ml of n-octadecyltrichlorosilane was added. Next, 5 g of dried magnetite and 5 ml of triethylamine were added to the three-necked flask, and the mixture was stirred under a nitrogen atmosphere for 48 hours.
FIG. 7 shows a reaction state when magnetite is treated with n-octadecyltrichlorosilane as a silane coupling agent.
By reacting magnetite with n-octadecyltrichlorosilane in triethylamine and dehydrated toluene, n-octadecyltrichlorosilanated magnetite is obtained.
The obtained solution was centrifuged, washed several times with toluene by decantation, and then washed sequentially with tetrahydrofuran and methanol.
Finally, after washing with acetone, the supernatant was removed as much as possible and dried under reduced pressure to obtain hydrophobic magnetic particles P.
[0039]
(Evaluation of hydrophobic magnetic particles P)
The obtained hydrophobic magnetic particles P were weighed at 2500 N / cm. ² , And water droplets were dropped on the surface to evaluate hydrophobicity. There was no absorption in the pellets, and the water droplets became spheres and showed water repellency.
As a comparative example, one obtained by forming a pellet using the above magnetite (without surface treatment) was used. In the same manner, when the hydrophobicity was evaluated, water droplets did not become spheres but only penetrated into the pellet surface and passed through the inside of the pellet, and no water repellency was observed.
From the above, it was confirmed that the surface of the hydrophobic magnetic particles P was apparently hydrophobic.
[0040]
(Removal of oil H from water-soluble cutting oil)
2 g of the obtained hydrophobic magnetic particles P were added to a used water-soluble cutting oil aqueous solution diluted to twice 20 ml. After the addition, when sufficiently stirred, the used cutting oil aqueous solution which had become cloudy became transparent. Therefore, the used water-soluble cutting oil was adsorbed on the hydrophobic magnetic particles P, and the treated water could be purified.
[0041]
(Separation of oil H in water-soluble cutting oil)
The treatment liquid was subjected to magnetic separation, and the supernatant was removed. 10 ml of methanol was added to the remaining precipitate, followed by thorough stirring. After the stirring, the odor of the solution became the odor of the cutting oil. Therefore, the used water-soluble cutting oil and its decay adsorbed from the hydrophobic magnetic particles P could be extracted, and the surface of the hydrophobic magnetic particles P could be washed. Using the above-mentioned hydrophobic magnetic particles P washed after use, they were again added to a used water-soluble cutting oil aqueous solution diluted twice and stirred. The treated solution turned from cloudy to clear and could be purified. Therefore, it can be seen that it can be reused.
[0042]
[Example 2]
Using iron sand for the magnetic particles, for surface treatment of the iron sand, 50 ml of dehydrated toluene was taken in a constant-pressure dropping funnel, and 5 ml of n-octadecyltrichlorosilane was added. Next, 5 g of dried magnetite and 5 ml of triethylamine were added to the three-necked flask, and the mixture was stirred under a nitrogen atmosphere for 48 hours.
The obtained solution was centrifuged, washed several times with toluene by decantation, and then washed sequentially with tetrahydrofuran and methanol.
Finally, after washing with acetone, the supernatant was removed as much as possible and dried under reduced pressure to obtain hydrophobic magnetic particles P.
[0043]
(Evaluation of hydrophobic magnetic particles P)
A pellet was formed in the same manner as in Example 1, and a hydrophobicity test was performed. As a result, the same effect as in Example 1 was obtained.
[0044]
【The invention's effect】
As described above, according to the method and system for removing oil from a water-soluble cutting oil of the present invention, the oil of the water-soluble cutting oil is adsorbed on the hydrophobic magnetic particles having hydrophobic groups on the surface, and The hydrophobic magnetic particles to which the oil of the hydrophobic cutting oil is adsorbed are magnetically captured and removed from the liquid tank, so the oil of the water-soluble cutting oil is adsorbed by the hydrophobic interaction using the hydrophobic magnetic particles. Thus, the hydrophobic magnetic particles can be magnetically captured, and the oil of the water-soluble cutting oil can be captured together with the hydrophobic magnetic particles. The captured hydrophobic magnetic particles can be magnetically removed without being removed by washing or a separation membrane, so that the treatment efficiency is excellent. In addition, since the oil of the water-soluble cutting oil and the hydrophobic magnetic particles are adsorbed by the hydrophobic interaction, separation with an organic solvent can be facilitated. As a result, the present invention is extremely useful for treating used water-soluble cutting oil.
[0045]
In addition, in the case where the oil of the water-soluble cutting oil is separated from the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed, the separated hydrophobic magnetic particles are adsorbed with the oil of the water-soluble cutting oil. Can be reused.
Further, a charging step of charging the hydrophobic magnetic particles into a liquid tank containing a water-soluble cutting oil, and an adsorption step of adsorbing the hydrophobic magnetic particles and the water-soluble cutting oil in water containing oil of the water-soluble cutting oil. A removing step of removing water-soluble cutting oil adsorbed on the hydrophobic magnetic particles from the liquid tank, and a separating step of separating water-soluble cutting oil from the water-soluble cutting oil adsorbed on the hydrophobic magnetic particles And an extraction step of extracting the separated hydrophobic magnetic particles, the oil trapping process of the water-soluble cutting oil, the separation process of the oil of the water-soluble cutting oil from the hydrophobic magnetic particles. In addition, the extraction process for reusing the hydrophobic magnetic particles can be efficiently performed.
[0046]
Furthermore, if the adsorption step is configured to stir so that the hydrophobic magnetic particles and the water-soluble cutting oil can be brought into contact with each other, the hydrophobic magnetic particles and the water-soluble The oil of the cutting oil can be agglomerated and easily adsorbed by hydrophobic interaction.
When the separation step is performed by mixing the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed with the organic solvent, the separation of the oil of the water-soluble cutting oil adsorbed by the hydrophobic interaction is performed. It can be easily separated from the hydrophobic magnetic particles with an organic solvent.
Further, when the extraction step is performed by magnetically adsorbing the hydrophobic magnetic particles, the hydrophobic magnetic particles can be collected and reused by a magnet.
[Brief description of the drawings]
FIG. 1 is a diagram of a water-soluble cutting oil oil removal processing system that realizes a water-soluble cutting oil oil removal processing method according to an embodiment of the present invention.
FIG. 2 shows a trapping means of a water-soluble cutting oil oil removal treatment system for realizing a water-soluble cutting oil removal treatment method according to an embodiment of the present invention, and (1) shows a configuration of the trapping means. It is a figure and (2) is a figure which shows a magnetic filter.
FIG. 3 is a diagram illustrating processing steps of an oil removal processing method for a water-soluble cutting oil according to an embodiment of the present invention.
FIG. 4 is a diagram showing a state of catching oil of the water-soluble cutting oil in the oil-removing method of the water-soluble cutting oil according to the embodiment of the present invention.
FIG. 5 is a view showing hydrophobic groups of hydrophobic magnetic particles used in the method for removing oil from a water-soluble cutting oil according to the embodiment of the present invention.
FIG. 6 is a diagram showing a standard example of a water-soluble cutting oil.
FIG. 7 is a diagram showing a preparation example of hydrophobic magnetic particles in an example of the present invention.
[Explanation of symbols]
S Water-soluble cutting oil removal system
P hydrophobic magnetic particles
M magnetic particles
W hydrophobic group
H Water-soluble cutting oil
1 liquid tank
2 Stirring means
3 Capture means
4 Separation tank
5 Extraction means
6 Magnetization device
7 Magnetic filter

Claims

An oil removal treatment method for a water-soluble cutting oil for removing oil of the water-soluble cutting oil from a liquid tank containing the water-soluble cutting oil,
The oil of the water-soluble cutting oil is adsorbed on the hydrophobic magnetic particles having a hydrophobic group on the surface, and the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed are magnetically captured and removed from the liquid tank. An oil removal treatment method for a water-soluble cutting oil.

An oil removal method for a water-soluble cutting oil, comprising separating the water-soluble cutting oil from the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed.

A charging step of charging the hydrophobic magnetic particles into the liquid tank containing the water-soluble cutting oil,
In the liquid tank, an adsorption step of adsorbing the hydrophobic magnetic particles and the oil of the water-soluble cutting oil,
A removing step of removing the oil of the water-soluble cutting oil adsorbed on the hydrophobic magnetic particles from the liquid tank,
A separation step of separating the oil of the water-soluble cutting oil adsorbed on the hydrophobic magnetic particles described above,
An extraction step of extracting the separated hydrophobic magnetic particles,
3. The method for removing oil from a water-soluble cutting oil according to claim 1, wherein the method comprises:

4. The method for removing oil from a water-soluble cutting oil according to claim 3, wherein the adsorbing step is performed by stirring the hydrophobic magnetic particles and the oil of the water-soluble cutting oil so as to be able to contact each other.

5. The method for removing oil from a water-soluble cutting oil according to claim 3, wherein the separation step is performed by mixing hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed with an organic solvent.

6. The oil removal treatment method for a water-soluble cutting oil according to claim 3, wherein the extraction step is performed by magnetically adsorbing the hydrophobic magnetic particles.

In a water-soluble cutting oil oil removal treatment system that removes oil from a water-soluble cutting oil,
A liquid tank containing the water-soluble cutting oil and hydrophobic magnetic particles having a hydrophobic group on the surface, and a mixed liquid in the liquid tank is mixed with the oil of the water-soluble cutting oil and the hydrophobic magnetic particles. A stirrer for stirring so as to adsorb it
Capture means for capturing the hydrophobic magnetic particles to which the water-soluble cutting oil is adsorbed from the mixed solution,
A separation tank of an organic solvent for separating the oil of the water-soluble cutting oil from the hydrophobic magnetic particles to which the oil of the water-soluble cutting oil is adsorbed and captured,
An oil removal treatment system for a water-soluble cutting oil, comprising: an extraction unit for extracting the hydrophobic magnetic particles separated in the separation tank.

8. The oil removal of a water-soluble cutting oil according to claim 7, wherein said capturing means is provided with a magnetizing device and a magnetic filter which captures said hydrophobic magnetic particles by being magnetized by said magnetizing device. Processing system.

9. The oil removal treatment of a water-soluble cutting oil according to claim 7, wherein said extraction means is provided with a magnetic extraction unit for magnetically extracting hydrophobic magnetic particles separated in said separation tank. system.