JP2019155292A - Water treatment chemical and water treatment method - Google Patents
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本発明は、水処理用薬剤、およびその水処理用薬剤を用いた水処理方法に関する。 The present invention relates to a water treatment agent and a water treatment method using the water treatment agent.
水処理設備においては、必要に応じて各種の殺菌処理等の水処理が行われる（例えば、特許文献１参照）。水処理設備における殺菌処理は、設備や材への影響、処理水質への影響、コスト等を検討しながら決定、実施される。殺菌剤としては、次亜塩素酸、次亜臭素酸、過酸化水素等の無機系薬剤や、有機系薬剤が使用される。また、熱水殺菌が行われることもある。 In the water treatment facility, water treatment such as various sterilization treatments is performed as necessary (see, for example, Patent Document 1). The sterilization treatment in the water treatment facility is determined and implemented while considering the influence on the equipment and materials, the influence on the treated water quality, the cost, and the like. As the disinfectant, inorganic chemicals such as hypochlorous acid, hypobromous acid, and hydrogen peroxide, and organic chemicals are used. Moreover, hot water sterilization may be performed.
例えば、純水製造工程および超純水製造工程における逆浸透膜（ＲＯ膜）装置においては、系内の微生物の増殖に伴う微生物由来のスライム等により、透過水量の低下、処理水質の悪化、通水差圧の上昇等の性能低下が引き起こされることがある。これらの微生物汚染等を抑制するために種々の殺菌剤（スライム抑制剤）が提案されている。殺菌剤としては、一般的には、無機系薬剤である次亜塩素酸等の酸化系殺菌剤や、有機系薬剤である有機窒素系殺菌剤、ハロシアノアセトアミド系殺菌剤等が知られている（例えば、特許文献２，３参照）。 For example, in a reverse osmosis membrane (RO membrane) apparatus in a pure water production process and an ultrapure water production process, a microbial-derived slime associated with the growth of microorganisms in the system causes a decrease in the amount of permeate, deterioration in the quality of treated water, Performance degradation such as an increase in water differential pressure may be caused. Various fungicides (slime inhibitors) have been proposed to suppress these microbial contaminations. As the bactericides, in general, oxidizing bactericides such as hypochlorous acid which are inorganic chemicals, organic nitrogen bactericides such as organic chemicals, halocyanoacetamide bactericides and the like are known. (For example, see Patent Documents 2 and 3).
酸化系殺菌剤の中でも次亜塩素酸は、汎用的に使用される水処理用の薬剤であるが、酸化力が強く、後段の設備や材（逆浸透膜やイオン交換樹脂等）にダメージを与えることがあるため、殺菌処理後の余剰な薬剤は、還元剤や活性炭等で処理する必要がある。また、薬剤注入により後段の塩負荷が増加する。 Among the oxidizing disinfectants, hypochlorous acid is a commonly used water treatment agent, but it has strong oxidizing power and damages equipment and materials in the subsequent stages (such as reverse osmosis membranes and ion exchange resins). Therefore, it is necessary to treat the excess drug after the sterilization treatment with a reducing agent, activated carbon or the like. Further, the salt load in the subsequent stage increases due to the drug injection.
過酸化水素は後段の塩負荷を増加させないが、例えば％オーダの高濃度での処理が必要であり、殺菌処理後の処理水について過酸化水素の分解処理が必要となる（例えば、特許文献４参照）。 Hydrogen peroxide does not increase the salt load in the latter stage, but treatment at a high concentration, for example, on the order of% is required, and hydrogen peroxide decomposition treatment is required for the treated water after sterilization treatment (for example, Patent Document 4). reference).
有機系薬剤は、処理水のＴＯＣの増加等に注意が必要である（例えば、特許文献５，６参照）。また、熱水殺菌は、設備の耐熱性や、処理コスト等に課題がある。 For organic chemicals, attention must be paid to an increase in the TOC of treated water (see, for example, Patent Documents 5 and 6). In addition, hot water sterilization has problems in heat resistance of equipment, processing costs, and the like.
以上のことから、新たな殺菌剤等の水処理用薬剤が求められている。 From the above, water treatment chemicals such as a new bactericidal agent are demanded.
ところで、次世代機能性材料として酸化グラフェンが注目されている。酸化グラフェンは抗菌性を有しており、酸化グラフェンを口腔内に存在する細菌に対する抗菌性付与材料として利用することが提案されている（特許文献７）。しかし、酸化グラフェンを、水処理用薬剤として利用する具体的な報告は見当たらない。 By the way, graphene oxide attracts attention as a next-generation functional material. Graphene oxide has antibacterial properties, and it has been proposed to use graphene oxide as a material for imparting antibacterial properties against bacteria present in the oral cavity (Patent Document 7). However, there are no specific reports on the use of graphene oxide as a water treatment agent.
本発明の目的は、新たな水処理用薬剤、およびその水処理用薬剤を用いた水処理方法を提供することにある。 An object of the present invention is to provide a new water treatment chemical and a water treatment method using the water treatment chemical.
本発明は、酸化グラフェンを含有する水処理用薬剤である。 The present invention is a water treatment agent containing graphene oxide.
前記水処理用薬剤において、前記酸化グラフェンの平面形状が、長手方向の大きさで０．１〜５０μｍの範囲であることが好ましい。 In the water treatment agent, the planar shape of the graphene oxide is preferably in the range of 0.1 to 50 μm in the longitudinal direction.
前記水処理用薬剤において、前記酸化グラフェンの酸素含有量が、２５〜６５重量％の範囲であることが好ましい。 In the water treatment agent, the oxygen content of the graphene oxide is preferably in the range of 25 to 65% by weight.
前記水処理用薬剤において、前記酸化グラフェンのＸＰＳ分析において、Ｃ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度およびＣ＝Ｏピーク強度の少なくとも１つが０．３倍以上であることが好ましい。 In the water treatment agent, in XPS analysis of the graphene oxide, it is preferable that at least one of the C—O peak intensity and the C═O peak intensity is 0.3 times or more with respect to the C—C peak intensity.
前記水処理用薬剤において、前記酸化グラフェンの厚さが、炭素原子１０層以下であることが好ましい。 In the water treatment agent, it is preferable that the graphene oxide has a thickness of 10 layers or less.
前記水処理用薬剤において、前記水処理用薬剤中の前記酸化グラフェンの含有量が、０．０１〜５０重量％の範囲であることが好ましい。 In the water treatment agent, the content of the graphene oxide in the water treatment agent is preferably in the range of 0.01 to 50% by weight.
前記水処理用薬剤において、前記水処理用薬剤のｐＨが、０〜８の範囲であることが好ましい。 In the water treatment chemical, the pH of the water treatment chemical is preferably in the range of 0-8.
前記水処理用薬剤において、前記酸化グラフェンは、硫酸に黒鉛を加えて、過マンガン酸カリウムと５０℃以下で反応させたものであることが好ましい。 In the water treatment agent, the graphene oxide is preferably obtained by adding graphite to sulfuric acid and reacting with potassium permanganate at 50 ° C. or lower.
本発明は、前記水処理用薬剤を用いて被処理水の水処理を行う水処理方法である。 The present invention is a water treatment method for performing water treatment of water to be treated using the water treatment chemical.
本発明は、前記水処理用薬剤を用いて被処理水の殺菌処理を行う水処理方法である。 The present invention is a water treatment method for sterilizing water to be treated using the water treatment chemical.
前記水処理方法において、前記殺菌処理における前記被処理水中の前記酸化グラフェンの濃度が、０．５〜５０ｍｇ／Ｌの範囲であることが好ましい。 In the water treatment method, the concentration of the graphene oxide in the water to be treated in the sterilization treatment is preferably in the range of 0.5 to 50 mg / L.
本発明により、新たな水処理用薬剤、およびその水処理用薬剤を用いた水処理方法を提供することができる。 According to the present invention, a new water treatment agent and a water treatment method using the water treatment agent can be provided.
本発明の実施の形態について以下説明する。本実施形態は本発明を実施する一例であって、本発明は本実施形態に限定されるものではない。 Embodiments of the present invention will be described below. This embodiment is an example for carrying out the present invention, and the present invention is not limited to this embodiment.
＜水処理用薬剤＞
本発明者らは、酸化グラフェンが適度な殺菌作用等を有し、新たな水処理用薬剤として利用できることを見出した。
<Water treatment chemicals>
The present inventors have found that graphene oxide has an appropriate bactericidal action and can be used as a new water treatment agent.
酸化グラフェンは、黒鉛（グラファイト）を特定の方法で酸化することにより得られる。黒鉛は、六角形の格子状に並んだ炭素原子で構成された炭素シートの積層体であり、例えば、Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法等によって黒鉛を酸化させることにより各炭素シートを酸化させ、酸化に伴って各炭素シートを個々に分離させ、酸化グラフェンとすることができる。なお、「酸化グラフェン」は、通常、酸化された１層の炭素シートのことを指すが、黒鉛を酸化させた場合に、必ずしも１層の炭素シートとなるとは限らず、複数の炭素シートが重なった状態となることもあり、このような酸化された炭素シートが１層または複数層（例えば、１０層以下）となっている状態を、本明細書では「酸化グラフェン」と呼ぶ。 Graphene oxide can be obtained by oxidizing graphite (graphite) by a specific method. Graphite is a laminate of carbon sheets composed of carbon atoms arranged in a hexagonal lattice. For example, each carbon sheet is oxidized by oxidizing graphite by the Hummers-Offeman method, etc. Each carbon sheet can be individually separated into graphene oxide. “Graphene oxide” usually refers to an oxidized single-layer carbon sheet, but when graphite is oxidized, it does not necessarily become a single-layer carbon sheet, and a plurality of carbon sheets overlap. In this specification, a state in which such an oxidized carbon sheet has one or more layers (for example, 10 layers or less) is referred to as “graphene oxide”.
酸化グラフェンの構造は製造方法によっても変わり、詳細な構造は明らかではないが、酸化により、例えば、エポキシ基、水酸基、スルホン酸基、カルボキシル基等の官能基が炭素シートの炭素原子に導入されていると考えられている。製造方法、原料の黒鉛、用いる酸や酸化剤の種類および量、反応時間等によって得られる酸化グラフェンの構造、性質等が異なる。 The structure of graphene oxide varies depending on the production method, and the detailed structure is not clear. However, due to oxidation, functional groups such as epoxy groups, hydroxyl groups, sulfonic acid groups, and carboxyl groups are introduced into carbon atoms of the carbon sheet. It is believed that The structure, properties, and the like of the graphene oxide obtained vary depending on the production method, raw material graphite, the type and amount of the acid and oxidizing agent used, the reaction time, and the like.
本発明の実施形態に係る水処理用薬剤は、この酸化された炭素シートが１層または複数層となっている「酸化グラフェン」を含有するものである。ただし、本実施形態に係る水処理用薬剤には、酸化グラフェンの凝集体や未剥離の黒鉛が含まれていても構わない。また、本実施形態に係る水処理用薬剤には、完全に分散しておらず、粒状の物質（例えば凝集体や黒鉛）が含まれていても構わない。これらの物質は、重量で１０％以下含まれていてもよく、好ましくは重量で１％以下含まれていてもよい。 The chemical for water treatment according to the embodiment of the present invention contains “graphene oxide” in which the oxidized carbon sheet has one or more layers. However, the water treatment agent according to the present embodiment may contain graphene oxide aggregates and unpeeled graphite. Moreover, the chemical | medical agent for water treatment which concerns on this embodiment may not be completely disperse | distributed, but a granular substance (for example, aggregate and graphite) may be contained. These substances may be contained in an amount of 10% or less by weight, and preferably 1% or less in weight.
本実施形態に係る水処理用薬剤に含まれる酸化グラフェンは、例えば、Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法（Hummers WS, Offeman R, Preparation of graphite oxide. J. Am. Chem Soc, 1958; 80: 1339.参照）で製造されるが、製造方法は、特に限定されるものではない。Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法は、一般的に、硝酸ナトリウムと、硫酸と、過マンガン酸カリウムとを含む混合液に粉末状の黒鉛を加えることにより黒鉛を酸化させ、酸化グラフェンを生じさせる方法である。Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法の他には、Ｂｒｏｄｉｅ法（Brodie BC, Sur le poids atomique du graphite. Ann. Chem. Phys, 1860; 59: 466-472.参照）、Ｓｔａｕｄｅｎｍａｉｅｒ法（Staudenmaier L, Verfahren zur darstellung der graphitsaure. Ber. Dtsch. Chem Ges, 1898; 31: 1481-1499.参照）等を用いてもよい。Ｂｒｏｄｉｅ法は、過マンガン酸カリウムの代わりに塩素酸カリウムを用いる方法であり、Ｓｔａｕｄｅｎｍａｉｅｒ法は、過マンガン酸カリウムの代わりに塩素酸カリウムを、硫酸の代わりに硫酸と硝酸の混合酸を用いる方法である。これらの方法を組み合わせたり、繰り返し行ったりすることにより、酸素含有量を増やしてもよい。Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法等によって酸化グラフェンを得た後、必要に応じて、遠心分離法、膜ろ過法等により、酸化グラフェンを濃縮、精製すればよい。 The graphene oxide contained in the water treatment agent according to the present embodiment is, for example, by the Hummers-Offeman method (see Hummers WS, Offeman R, Preparation of graphite oxide. J. Am. Chem Soc, 1958; 80: 1339.). Although manufactured, the manufacturing method is not particularly limited. The Hummers-Offeman method is generally a method in which graphite is oxidized by adding powdered graphite to a mixed solution containing sodium nitrate, sulfuric acid, and potassium permanganate to generate graphene oxide. In addition to the Hummers-Offeman method, the Brodie method (see Brodie BC, Sur le poids atomique du graphite. Ann. Chem. Phys, 1860; 59: 466-472.) And the Staudenmaier method (Staudenmaier L, Verfahren zur darstellung der graphitsaure Ber. Dtsch. Chem Ges, 1898; 31: 1481-1499.) May also be used. The Brodie method uses potassium chlorate instead of potassium permanganate, and the Staudenmeier method uses potassium chlorate instead of potassium permanganate and a mixed acid of sulfuric acid and nitric acid instead of sulfuric acid. is there. The oxygen content may be increased by combining or repeatedly performing these methods. After obtaining graphene oxide by the Hummers-Offeman method or the like, the graphene oxide may be concentrated and purified by a centrifugal separation method, a membrane filtration method, or the like, if necessary.
本実施形態に係る水処理用薬剤において、酸化グラフェンは、濃硫酸等の硫酸に黒鉛を加えて、過マンガン酸カリウムと５０℃以下で反応させたものであることが好ましい。すなわち、酸化グラフェンは、Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法、またはＨｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法を修正した方法で製造されたものであることが好ましい。この方法は、酸化グラフェンの製造に数日から１週間程度を要するＢｒｏｄｉｅ法やＳｔａｕｄｅｎｍａｉｅｒ法に比べて、製造時間の短縮が可能であり、ＣｌＯ２の生成を避けられることから安全性が高く、過剰に酸化されていない酸化グラフェンが得られるという利点がある。また、反応温度を５０℃以下とすることで、過剰な酸化が抑制される。「過剰な酸化反応が抑制される」ことは、反応を制御して、所望の特性の酸化グラフェンを得ることができることを意味し、酸化グラフェンの収率が高まり、酸化グラフェンの品質のばらつきが少なくなり、酸化グラフェンの品質が高まる。「過剰に酸化された」酸化グラフェンとは、原料の黒鉛から剥離された平面シート状の酸化グラフェンが酸化ダメージを受けることを意味し、例えば、酸化によって、平面シート形状が崩れ、シート形状分布が広がり、小さくなったり、穴のあいたシート形状の酸化グラフェンが得られることになる。 In the water treatment agent according to the present embodiment, the graphene oxide is preferably obtained by adding graphite to sulfuric acid such as concentrated sulfuric acid and reacting with potassium permanganate at 50 ° C. or lower. That is, it is preferable that the graphene oxide is manufactured by the Hummers-Offeman method or a method obtained by modifying the Hummers-Offeman method. Compared with the Brodie method and the Staudenmeier method, which require several days to a week or so for the production of graphene oxide, this method can reduce the production time and avoids the generation of ClO 2 , which is highly safe and excessive. There is an advantage that non-oxidized graphene oxide can be obtained. Moreover, excessive oxidation is suppressed by making reaction temperature 50 degrees C or less. “Suppressing excessive oxidation reaction” means that the reaction can be controlled to obtain graphene oxide having the desired characteristics, and the yield of graphene oxide is increased, and there is little variation in the quality of graphene oxide. This improves the quality of graphene oxide. “Over-oxidized” graphene oxide means that the planar sheet-like graphene oxide peeled from the raw graphite is subject to oxidative damage. For example, the planar sheet shape collapses due to oxidation, and the sheet shape distribution is A sheet-shaped graphene oxide that is widened, reduced, or has holes is obtained.
酸化グラフェンの平面形状は、長手方向の大きさで０．１〜５０μｍの範囲であることが好ましく、０．５〜３０μｍの範囲であることがより好ましく、１〜１０μｍの範囲であることがさらに好ましい。酸化グラフェンの平面形状が長手方向の大きさで０．１μｍ未満であると、Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法等による反応後の遠心分離法、膜ろ過法等による濃縮、精製において酸化グラフェンを分離、除去しにくい場合があり、また、水処理薬剤として使用した後の被処理水中に添加された酸化グラフェンの膜ろ過法等による固液分離において酸化グラフェンを分離、除去しにくい場合がある。酸化グラフェンの平面形状が長手方向の大きさで５０μｍを超えると、凝集してしまい、平面状に剥離した表面積が高い酸化グラフェンの表面積が小さくなり、期待する水処理効果が得られない場合がある。同様の化学組成（酸化度）で、同じ重量濃度の場合、小粒径の方がエッジ効果により、単位重量あたりの粒子のエッジの割合が増え、エッジ周辺に官能基が多く存在し易くなり、官能基の密度が増えることから、殺菌効果等が高くなると考えられる。原料の違い、製造方法の違い、製造のしやすさ、濃縮のしやすさ、溶媒への分散、凝集のしやすさ、水処理後の後処理のしやすさ等を考慮して、水処理用薬剤に含有される酸化グラフェンの大きさを適宜決定してもよい。なお、酸化グラフェンの長手方向の大きさは、酸化グラフェンのＳＥＭ観察において、３０個の粒子を任意に選択し、選択した３０個の粒子について測定した長手方向の大きさの平均値として求めたものである。なお、用いる酸化グラフェン中に、長手方向の大きさが上記範囲に含まれないものが全体の１〜３０重量％程度は含まれていてもよい。 The planar shape of graphene oxide is preferably in the range of 0.1 to 50 μm in terms of the size in the longitudinal direction, more preferably in the range of 0.5 to 30 μm, and further in the range of 1 to 10 μm. preferable. When the planar shape of graphene oxide is less than 0.1 μm in the longitudinal direction, it is difficult to separate and remove graphene oxide in the concentration and purification by the centrifugal method after the reaction by the Hummers-Offeman method, the membrane filtration method, etc. In some cases, it is difficult to separate and remove graphene oxide in solid-liquid separation by membrane filtration or the like of graphene oxide added to water to be treated after being used as a water treatment chemical. When the planar shape of the graphene oxide exceeds 50 μm in the longitudinal direction, the graphene aggregates, and the surface area of the graphene oxide having a high surface area exfoliated in a planar shape is reduced, so that the expected water treatment effect may not be obtained. . In the case of the same chemical composition (oxidation degree) and the same weight concentration, the small particle size has an edge effect, the ratio of the edge of the particle per unit weight increases, and there are more functional groups around the edge. Since the density of the functional group is increased, it is considered that the bactericidal effect is enhanced. Water treatment considering differences in raw materials, production methods, ease of production, ease of concentration, dispersion in solvent, ease of aggregation, ease of post-treatment after water treatment, etc. You may determine suitably the magnitude | size of the graphene oxide contained in the chemical | medical agent. In addition, the longitudinal size of graphene oxide was obtained as an average value of the longitudinal sizes measured for 30 selected particles in an SEM observation of graphene oxide. It is. In addition, the graphene oxide to be used may contain about 1 to 30% by weight of the whole in which the size in the longitudinal direction is not included in the above range.
酸化グラフェンの厚さは、炭素原子１０層以下であることが好ましく、５層以下であることがより好ましく、１層であることがさらに好ましい。酸化グラフェンの厚さは、炭素原子１０層で約１０ｎｍの厚さとなる。酸化グラフェンの厚さが１０層を超えると、十分な殺菌性能を示さない場合がある。炭素原子１０層酸化グラフェンの厚さが薄い（層数が少ない）ほど、酸化グラフェンの単位重量（モル）あたりの表面積が大きくなり、殺菌効果（殺菌効率）等が高くなる。一方、酸化グラフェンの厚さを薄くする（層をより剥離する）ためには、よりエネルギーをかける必要がある。また、酸化グラフェンの保管中に凝集する可能性もあるが、凝集が発生した場合に、再度剥離するための処理を行うことや、凝集を抑制するために、分散剤を添加することは、コストの増加につながる。また、純水製造用の殺菌剤等の水処理用薬剤として使用する場合、分散剤の添加は余計な負荷となる可能性がある。なお、酸化グラフェンの厚さは、ＡＦＭ（原子間力顕微鏡）によりタッピングモードで、任意に選択した１０個の粒子について測定した厚さの平均値として求めたものである。なお、用いる酸化グラフェン中に、厚さが１０層を超えるものが全体の０〜２０重量％程度は含まれていてもよい。 The thickness of graphene oxide is preferably 10 layers or less, more preferably 5 layers or less, and even more preferably 1 layer. The thickness of graphene oxide is about 10 nm with 10 layers of carbon atoms. When the thickness of the graphene oxide exceeds 10 layers, sufficient sterilization performance may not be exhibited. The thinner the carbon atom 10-layer graphene oxide (the smaller the number of layers), the larger the surface area per unit weight (mole) of graphene oxide and the higher the bactericidal effect (bactericidal efficiency). On the other hand, in order to reduce the thickness of the graphene oxide (more peel the layer), it is necessary to apply more energy. In addition, there is a possibility of aggregation during storage of graphene oxide, but when aggregation occurs, it is costly to perform a treatment for peeling again and to add a dispersant to suppress aggregation. Leads to an increase in Moreover, when using it as chemical | medical agents for water treatments, such as a disinfectant for pure water manufacture, addition of a dispersing agent may become an extra load. The thickness of graphene oxide is obtained as an average value of thicknesses measured for 10 arbitrarily selected particles in the tapping mode by AFM (Atomic Force Microscope). In addition, the graphene oxide to be used may include about 0 to 20 wt% of the total thickness exceeding 10 layers.
酸化グラフェンの酸素含有量は、２５〜６５重量％の範囲であることが好ましく、３０〜６０重量％の範囲であることがより好ましく、４５〜６０重量％の範囲であることがさらに好ましい。酸化グラフェンの酸素含有量が２５重量％未満であると、酸化グラフェンが凝集する場合があり、６５重量％を超えると、酸化グラフェンの合成が困難となる場合がある。同様のサイズの場合、酸化度が高い方が酸化性の官能基の割合が多くなり、殺菌効果等が高くなる。酸化性の官能基の割合は酸素含有量によって規定することができる。酸化グラフェンの酸化度は酸化グラフェンの製造のときの酸化条件等で調整することができる。製造コストや水処理用薬剤の使用目的等に応じて酸化条件は適宜決定してもよい。酸化グラフェンの酸素含有量は、ＣＨＮ有機元素分析で求めたＣ，Ｈ，Ｎの値を１００％から引いた値である。 The oxygen content of graphene oxide is preferably in the range of 25 to 65% by weight, more preferably in the range of 30 to 60% by weight, and still more preferably in the range of 45 to 60% by weight. When the oxygen content of graphene oxide is less than 25% by weight, graphene oxide may aggregate, and when it exceeds 65% by weight, synthesis of graphene oxide may be difficult. In the case of the same size, the higher the degree of oxidation, the higher the proportion of oxidizing functional groups, and the higher the bactericidal effect and the like. The proportion of the oxidizable functional group can be defined by the oxygen content. The degree of oxidation of graphene oxide can be adjusted by the oxidation conditions during the production of graphene oxide. The oxidation conditions may be appropriately determined according to the manufacturing cost, the purpose of use of the water treatment chemical, and the like. The oxygen content of graphene oxide is a value obtained by subtracting the C, H, and N values obtained by CHN organic element analysis from 100%.
酸化グラフェンの酸素含有量に関連し、酸化グラフェンのＸＰＳ分析において、Ｃ−Ｃ（グラフェン骨格の炭素−炭素の結合）ピーク強度に対して、Ｃ−Ｏ（官能基の炭素−酸素の一重結合）ピーク強度およびＣ＝Ｏ（官能基の炭素−酸素の二重結合）ピーク強度の少なくとも１つが大きいことが好ましい。酸化グラフェンのＸＰＳ分析において、Ｃ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度およびＣ＝Ｏピーク強度の少なくとも１つが０．３倍以上であることが好ましく、０．７倍以上であることがより好ましい。Ｃ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度およびＣ＝Ｏピーク強度の両方が０．３倍未満以下であると、親水性が低いため凝集する場合がある。なお、ＸＰＳ分析において、Ｃ−Ｃピークは、２８５ｅＶ付近に、Ｃ−Ｏピークは、２８６ｅＶ付近に、Ｃ＝Ｏピークは、２８８ｅＶ付近に現れる。 In relation to the oxygen content of graphene oxide, in the XPS analysis of graphene oxide, C—O (carbon-oxygen single bond of functional group) versus C—C (carbon-carbon bond of graphene skeleton) peak intensity It is preferable that at least one of the peak intensity and the C = O (carbon-oxygen double bond of functional group) peak intensity is large. In XPS analysis of graphene oxide, it is preferable that at least one of the C—O peak intensity and the C═O peak intensity is 0.3 times or more, and 0.7 times or more with respect to the C—C peak intensity. Is more preferable. When both the C—O peak intensity and the C═O peak intensity are less than 0.3 times or less than the C—C peak intensity, the hydrophilicity is low and aggregation may occur. In XPS analysis, the C—C peak appears near 285 eV, the C—O peak appears near 286 eV, and the C═O peak appears near 288 eV.
本実施形態に係る水処理用薬剤は、酸化グラフェンを含有するものであり、例えば、酸化グラフェンの溶液、分散液、ペースト、粉末、粒状ペレット等の形態とすることができる。溶液および分散液の溶媒としては、水や、メタノール等のアルコール、ジメチルスルホキシド（ＤＭＳＯ）、Ｎ，Ｎ−ジメチルホルムアミド（ＤＭＦ）、Ｎ−メチル−２−−ピロリドン（ＮＭＰ）等の極性有機溶媒等が挙げられる。 The chemical for water treatment according to the present embodiment contains graphene oxide, and can be in the form of, for example, a graphene oxide solution, dispersion, paste, powder, granular pellets, and the like. Examples of the solvent for the solution and the dispersion include water, alcohols such as methanol, polar organic solvents such as dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP). Is mentioned.
水処理用薬剤中の酸化グラフェンの含有量は、製造コスト、輸送コストや取り扱い等を考慮して、適切な濃度に調整すればよく、特に制限はないが、０．０１〜５０重量％の範囲であることが好ましく、０．１〜５０重量％の範囲であることがより好ましく、０．５〜３０重量％の範囲であることがさらに好ましく、１〜１０重量％の範囲であることが特に好ましい。水処理用薬剤が粉体の場合は、酸化グラフェンの含有量は１００重量％であってもよい。水処理用薬剤中の酸化グラフェンの含有量が０．１重量％未満であると、コスト的に不利になる場合がある。水処理用薬剤としては、酸化グラフェンは高濃度の方が望ましいが、５０重量％よりも濃度が高いと、濃縮操作にエネルギーがかかり、製造コストが高くなる場合や、長期保管で分散状態が不安定になるような場合があるため、必要以上に高濃度としなくてもよい。また、次亜塩素酸等の他の薬剤と混合して、複合薬剤として使用してもよい。 The content of graphene oxide in the water treatment agent may be adjusted to an appropriate concentration in consideration of production costs, transportation costs, handling, etc., and is not particularly limited, but is in the range of 0.01 to 50% by weight. Preferably in the range of 0.1 to 50% by weight, more preferably in the range of 0.5 to 30% by weight, and particularly preferably in the range of 1 to 10% by weight. preferable. When the water treatment chemical is a powder, the content of graphene oxide may be 100% by weight. If the content of graphene oxide in the water treatment chemical is less than 0.1% by weight, it may be disadvantageous in cost. As a water treatment agent, graphene oxide is desirable to have a high concentration. However, if the concentration is higher than 50% by weight, energy is applied to the concentration operation, resulting in an increase in production cost or a long-term storage and a poor dispersion state. Since it may become stable, the concentration need not be higher than necessary. Further, it may be mixed with other drugs such as hypochlorous acid and used as a combined drug.
水処理用薬剤のｐＨは、０〜８の範囲であることが好ましく、１〜７の範囲であることがより好ましく、３〜７の範囲であることがさらに好ましい。水処理用薬剤のｐＨが０未満であると、酸化グラフェンが十分剥離しない場合があり、８を超えると、凝集する場合がある。酸化グラフェンには、通常、酸化性官能基が存在するために、水溶液または分散液は酸性を示すが、安定的な分散状態を維持するため、必要に応じてｐＨ調整を行ってもよい。水処理用薬剤として使用する点で、ｐＨ調整は塩酸（ＨＣｌ）等の無機酸、水酸化ナトリウム（ＮａＯＨ）等の無機アルカリで行うことが好ましい。 The pH of the water treatment agent is preferably in the range of 0-8, more preferably in the range of 1-7, and even more preferably in the range of 3-7. If the pH of the water treatment agent is less than 0, graphene oxide may not be sufficiently peeled off, and if it exceeds 8, it may aggregate. Since graphene oxide usually has an oxidizing functional group, the aqueous solution or dispersion shows acidity, but pH may be adjusted as necessary to maintain a stable dispersion state. In terms of use as a water treatment chemical, pH adjustment is preferably performed with an inorganic acid such as hydrochloric acid (HCl) or an inorganic alkali such as sodium hydroxide (NaOH).
酸化グラフェンを含む水処理用薬剤の希釈条件は、純水で希釈した場合の導電率が被処理水の導電率以下（例えば１００μＳ／ｃｍ以下）となるような濃度であることが好ましい。また、次亜塩素酸等の酸化系殺菌剤にはないマイルドな条件で殺菌処理等の水処理を行う場合、酸化還元電位（ＯＲＰ）が次亜塩素酸等の酸化系殺菌剤での処理条件よりも低い（例えば、３００ｍＶ（ＮＨＥ）以下である）ことが好ましい。 The condition for diluting the water treatment agent containing graphene oxide is preferably a concentration such that the conductivity when diluted with pure water is less than or equal to the conductivity of the water to be treated (for example, 100 μS / cm or less). In addition, when water treatment such as sterilization is performed under mild conditions that are not found in oxidizing sterilizers such as hypochlorous acid, the oxidation-reduction potential (ORP) is a treatment condition with oxidizing sterilizers such as hypochlorous acid. Is preferably lower (for example, 300 mV (NHE) or less).
＜水処理用薬剤を用いた水処理方法＞
本実施形態に係る水処理方法は、上記水処理用薬剤を用いて被処理水の水処理を行う方法である。水処理としては、上記水処理用薬剤を用いて被処理水の処理を行うものであればよく、特に制限はないが、例えば、殺菌処理、吸着処理、凝集剤または凝集助剤として凝集処理、ＣＯＤ除去剤としてＣＯＤ除去処理、界面活性剤除去剤として界面活性剤除去処理等に用いられる。なお、本実施形態に係る水処理方法には、水処理用薬剤を改質剤として用いて改質した逆浸透膜等の膜を用いて水処理を行う水処理方法も含まれる。
<Water treatment method using chemicals for water treatment>
The water treatment method according to the present embodiment is a method for performing water treatment of water to be treated using the water treatment chemical. The water treatment is not particularly limited as long as the water to be treated is treated using the above water treatment agent, but for example, sterilization treatment, adsorption treatment, flocculation treatment as a flocculating agent or flocculating aid, It is used for COD removal treatment as a COD removal agent, surfactant removal treatment as a surfactant removal agent, and the like. The water treatment method according to the present embodiment includes a water treatment method in which water treatment is performed using a membrane such as a reverse osmosis membrane modified using a water treatment agent as a modifier.
酸化グラフェンを含む水処理用薬剤を希釈して、被処理水の殺菌処理等の水処理を行ってもよい。水処理用薬剤を被処理水に直接注入してもよいが、事前に希釈操作を行ってから、希釈液を被処理水に注入してもよい。 You may dilute the chemical | medical agent for water treatment containing a graphene oxide, and perform water treatments, such as a disinfection process of to-be-processed water. Although the chemical for water treatment may be directly injected into the water to be treated, the dilution liquid may be injected into the water to be treated after performing a dilution operation in advance.
殺菌処理における被処理水中の酸化グラフェンの濃度は、０．５〜５０ｍｇ／Ｌの範囲であることが好ましく、１〜１０ｍｇ／Ｌの範囲であることがより好ましい。被処理水中の酸化グラフェンの濃度が０．５ｍｇ／Ｌより低いと、十分な殺菌効果が得られない場合がある。被処理水中の酸化グラフェンの濃度が５０ｍｇ／Ｌよりも高いと、処理コストが高くなる場合がある。また、殺菌処理後の処理水の後処理の負荷が高くなる場合がある。 The concentration of graphene oxide in the water to be treated in the sterilization treatment is preferably in the range of 0.5 to 50 mg / L, and more preferably in the range of 1 to 10 mg / L. If the concentration of graphene oxide in the water to be treated is lower than 0.5 mg / L, a sufficient bactericidal effect may not be obtained. When the concentration of graphene oxide in the water to be treated is higher than 50 mg / L, the treatment cost may increase. Moreover, the post-processing load of the treated water after sterilization may become high.
次亜塩素酸等の酸化系殺菌剤による殺菌処理後は、還元剤や活性炭等による後処理が必要である。一方、本発明の実施形態に係る水処理方法において、酸化グラフェンは次亜塩素酸等の酸化系殺菌剤よりも酸化剤としてはマイルドであり、後段の設備や材（逆浸透膜やイオン交換樹脂等）に対する酸化劣化の程度を抑制することができる。また、酸化グラフェンは精密ろ過膜（ＭＦ膜）等を用いたろ過等で除去することができるため、後段の塩負荷の増加を抑制することができる。 After sterilization with an oxidizing sterilizer such as hypochlorous acid, post-treatment with a reducing agent or activated carbon is necessary. On the other hand, in the water treatment method according to the embodiment of the present invention, graphene oxide is milder as an oxidizing agent than an oxidizing disinfectant such as hypochlorous acid, and subsequent equipment and materials (reverse osmosis membrane and ion exchange resin) Etc.) can be suppressed. In addition, since graphene oxide can be removed by filtration using a microfiltration membrane (MF membrane) or the like, it is possible to suppress an increase in subsequent salt load.
以下、実施例および比較例を挙げ、本発明をより具体的に詳細に説明するが、本発明は、以下の実施例に限定されるものではない。 Hereinafter, although an example and a comparative example are given and the present invention is explained more concretely in detail, the present invention is not limited to the following examples.
［酸化グラフェン１の合成］
Ｈｕｍｍｅｒｓ−Ｏｆｆｅｍａｎ法を修正した方法である、文献（Naoki Morimoto et.al., Tailoring the oxygen content of graphite and reduced graphene oxide for specific applications, Nature Scientific Reports, 6:21715, DOI:10.1038/srep21715）に記載の方法で、黒鉛の３重量倍の過マンガン酸カリウムを用いて酸化グラフェン１を合成した。
[Synthesis of Graphene Oxide 1]
Described in the literature (Naoki Morimoto et.al., Tailoring the oxygen content of graphite and reduced graphene oxide for specific applications, Nature Scientific Reports, 6: 21715, DOI: 10.1038 / srep21715), which is a modified version of the Hummers-Offeman method. In this manner, graphene oxide 1 was synthesized using potassium permanganate 3 times as much as graphite.
得られた酸化グラフェン１のＳＥＭ写真を図１に、ＸＰＳ装置（光電子分光装置、日本電子株式会社製、ＪＰＳ−９０３０）によりＸＰＳ分析を行った結果を図３に示す。得られた酸化グラフェン１の平面形状は、長手方向の大きさで１０μｍであった。ＸＰＳ分析においてＣ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度は、１倍、Ｃ＝Ｏピーク強度は、０．１倍であった。酸素含有量は、５０重量％であった。酸化グラフェンの厚さは、炭素原子１０層以下であった。 The SEM photograph of the obtained graphene oxide 1 is shown in FIG. 1, and the results of XPS analysis using an XPS apparatus (photoelectron spectrometer, JPS-9030, JPS-9030) are shown in FIG. The planar shape of the obtained graphene oxide 1 was 10 μm in the size in the longitudinal direction. In XPS analysis, the C—O peak intensity was 1 time and the C═O peak intensity was 0.1 times the C—C peak intensity. The oxygen content was 50% by weight. The thickness of the graphene oxide was 10 carbon atoms or less.
なお、酸化グラフェンの長手方向の大きさは、ＳＥＭ（株式会社日立ハイテクノロジーズ製、Ｓ−５２００）を用いた酸化グラフェンのＳＥＭ観察において、３０個の粒子について測定した長手方向の大きさの平均値として求めた。酸化グラフェンの酸素含有量は、ＣＨＮ有機元素分析で求めたＣ，Ｈ，Ｎの値を１００％から引いた値として求めた。酸化グラフェンの厚さは、ＳＰＭ（走査型プローブ顕微鏡、株式会社島津製作所製、ＳＰＭ−９７００ＨＴ）によりタッピングモード条件で、１０個の粒子について測定した厚さの平均値として求めた。 In addition, the size in the longitudinal direction of graphene oxide is the average value of the size in the longitudinal direction measured for 30 particles in SEM observation of graphene oxide using SEM (manufactured by Hitachi High-Technologies Corporation, S-5200). As sought. The oxygen content of graphene oxide was determined as a value obtained by subtracting the C, H, and N values obtained by CHN organic elemental analysis from 100%. The thickness of the graphene oxide was determined as an average value of thicknesses measured for 10 particles under a tapping mode condition using an SPM (scanning probe microscope, manufactured by Shimadzu Corporation, SPM-9700HT).
［酸化グラフェン２の合成（高酸化品）］
上記文献に記載の方法で、黒鉛の５重量倍の過マンガン酸カリウムを用いて酸化グラフェン２を合成した。
[Synthesis of graphene oxide 2 (highly oxidized product)]
Graphene oxide 2 was synthesized by the method described in the above-mentioned document using potassium permanganate 5 times as much as graphite.
得られた酸化グラフェン２についてＸＰＳ装置（光電子分光装置、日本電子株式会社製、ＪＰＳ−９０３０）によりＸＰＳ分析を行った結果を図３に示す。得られた酸化グラフェン２の平面形状は、長手方向の大きさで１０μｍであった。ＸＰＳ分析においてＣ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度は、２倍、Ｃ＝Ｏピーク強度は、０．６倍であった。酸素含有量は、６０重量％であった。酸化グラフェンの厚さは、炭素原子１０層以下であった。 FIG. 3 shows the results of XPS analysis of the obtained graphene oxide 2 using an XPS apparatus (photoelectron spectrometer, JPS-9030, JPS-9030). The planar shape of the obtained graphene oxide 2 was 10 μm in the longitudinal direction. In XPS analysis, the C—O peak intensity was doubled and the C═O peak intensity was 0.6 times the C—C peak intensity. The oxygen content was 60% by weight. The thickness of the graphene oxide was 10 carbon atoms or less.
［酸化グラフェン３の合成（小粒径品）］
酸化グラフェン１を、高圧式ホモジナイザーを用いて１ｗｔ％分散液、１５０ＭＰａの条件で粉砕して、酸化グラフェン３を合成した。
[Synthesis of graphene oxide 3 (small particle size product)]
Graphene oxide 1 was pulverized using a high-pressure homogenizer under the conditions of 1 wt% dispersion and 150 MPa to synthesize graphene oxide 3.
得られた酸化グラフェン３のＳＥＭ写真を図２に示す。得られた酸化グラフェン３の平面形状は、長手方向の大きさで１μｍであった。ＸＰＳ分析においてＣ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度は、１倍、Ｃ＝Ｏピーク強度は、０．１倍であった。酸素含有量は、５０重量％であった。酸化グラフェンの厚さは、炭素原子１０層以下であった。 An SEM photograph of the obtained graphene oxide 3 is shown in FIG. The planar shape of the obtained graphene oxide 3 was 1 μm in the longitudinal direction. In XPS analysis, the C—O peak intensity was 1 time and the C═O peak intensity was 0.1 times the C—C peak intensity. The oxygen content was 50% by weight. The thickness of the graphene oxide was 10 carbon atoms or less.
［酸化グラフェン４］
Ａｌｄｒｉｃｈ社製の酸化グラフェン試薬（製品番号：７９４３４１−５０ＭＬ、ロット番号：ＭＫＣ０１７２Ｖ、炭素原子層：１５〜２０層、酸素含有量：４〜１０％、水分散液（酸化グラフェン濃度：１ｍｇ／ｍＬ））を、酸化グラフェン４として用いた。酸化グラフェン４の平面形状は、ＳＥＭ観察において長手方向の大きさで１μｍであった。ＸＰＳ分析においてＣ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度は、０．１倍、Ｃ＝Ｏピーク強度は、０．０４倍であった。
[Graphene oxide 4]
Graphene oxide reagent manufactured by Aldrich (product number: 794341-50ML, lot number: MKC0172V, carbon atom layer: 15-20 layer, oxygen content: 4-10%, aqueous dispersion (graphene oxide concentration: 1 mg / mL) ) Was used as graphene oxide 4. The planar shape of the graphene oxide 4 was 1 μm in the longitudinal direction in SEM observation. In XPS analysis, the C—O peak intensity was 0.1 times and the C═O peak intensity was 0.04 times the C—C peak intensity.
＜実施例＞
下記模擬水を被処理水として、酸化グラフェンの殺菌効果を確認した。水処理用薬剤として、酸化グラフェン１、酸化グラフェン２、酸化グラフェン３のそれぞれについて酸化グラフェンの含有量が１重量％となるように水に分散させた水分散液を用いた。酸化グラフェン４については、購入した試薬をそのまま水処理用薬剤として用いた。被処理水に水処理用薬剤を添加し、室温（２０〜３０℃）で放置し、所定時間経過後の一般細菌数を測定した。実験条件を以下に示し、結果を表１に示す。
<Example>
The sterilization effect of graphene oxide was confirmed using the following simulated water as treated water. As a water treatment agent, an aqueous dispersion was used in which each of graphene oxide 1, graphene oxide 2, and graphene oxide 3 was dispersed in water so that the content of graphene oxide was 1% by weight. For graphene oxide 4, the purchased reagent was used as a water treatment chemical as it was. A water treatment chemical was added to the water to be treated and allowed to stand at room temperature (20 to 30 ° C.), and the number of general bacteria after a predetermined time was measured. Experimental conditions are shown below, and the results are shown in Table 1.
（実験条件）
被処理水：相模原市南区西大沼（オルガノ株式会社開発センター内）の井戸水に普通ブイヨンを添加し、一般細菌数が１０６ＣＦＵ／ｍＬとなるよう調整した模擬水
水処理用薬剤：被処理水中の酸化グラフェンの濃度が１ｍｇ／Ｌ（実施例２では１０ｍｇ／Ｌ）となるよう添加
評価方法：薬剤添加後２時間、２４時間、４８時間後の一般細菌数を生物簡易測定器具（三愛石油製、サンアイバイオチェッカー）により測定
(Experimental conditions)
Water to be treated: Simulated water in which normal bouillon was added to well water in Nishionuma, Minami-ku, Sagamihara City (organo Co., Ltd. development center) to adjust the general bacterial count to 10 6 CFU / mL. Addition so that the concentration of graphene oxide in water is 1 mg / L (10 mg / L in Example 2) Evaluation method: The number of general bacteria after 2 hours, 24 hours, and 48 hours after the addition of the drug Manufactured by Sun Eye Bio Checker)
［実施例１］
酸化グラフェン１を含有する水処理用薬剤を、被処理水中の酸化グラフェンの濃度が１ｍｇ／Ｌとなるよう添加して、殺菌効果を確認した。結果を表１に示す。
[Example 1]
The chemical | medical agent for water treatment containing the graphene oxide 1 was added so that the density | concentration of the graphene oxide in to-be-processed water might be 1 mg / L, and the bactericidal effect was confirmed. The results are shown in Table 1.
［実施例２］
酸化グラフェン１を含有する水処理用薬剤を、被処理水中の酸化グラフェンの濃度が１０ｍｇ／Ｌとなるよう添加した以外は、実施例１と同様にして、殺菌効果を確認した。結果を表１に示す。
[Example 2]
The bactericidal effect was confirmed in the same manner as in Example 1 except that the water treatment chemical containing graphene oxide 1 was added so that the concentration of graphene oxide in the water to be treated was 10 mg / L. The results are shown in Table 1.
［実施例３］
酸化グラフェン１の代わりに酸化グラフェン２を含有する水処理用薬剤を用いた以外は、実施例１と同様にして、殺菌効果を確認した。結果を表１に示す。
[Example 3]
The bactericidal effect was confirmed in the same manner as in Example 1 except that a water treatment chemical containing graphene oxide 2 was used instead of graphene oxide 1. The results are shown in Table 1.
［実施例４］
酸化グラフェン１の代わりに酸化グラフェン３を含有する水処理用薬剤を用いた以外は、実施例１と同様にして、殺菌効果を確認した。結果を表１に示す。
[Example 4]
The bactericidal effect was confirmed in the same manner as in Example 1 except that a water treatment chemical containing graphene oxide 3 was used instead of graphene oxide 1. The results are shown in Table 1.
［実施例５］
酸化グラフェン１の代わりに酸化グラフェン４を含有する水処理用薬剤を用いた以外は、実施例１と同様にして、殺菌効果を確認した。結果を表１に示す。
[Example 5]
The bactericidal effect was confirmed in the same manner as in Example 1 except that a water treatment chemical containing graphene oxide 4 was used instead of graphene oxide 1. The results are shown in Table 1.
なお、酸化グラフェン１，２，３の水分散液（純水希釈液）における、酸化グラフェンの濃度（ｐｐｍ）と酸化還元電位（ｍＶ（ＮＨＥ））との関係を図４に示し、酸化グラフェンの濃度（ｐｐｍ）と導電率（μＳ／ｃｍ）との関係を図５に示し、酸化グラフェンの濃度（ｐｐｍ）とｐＨとの関係を図６に示す。 FIG. 4 shows the relationship between the graphene oxide concentration (ppm) and the oxidation-reduction potential (mV (NHE)) in an aqueous dispersion (pure water dilution) of graphene oxide 1, 2, and 3. FIG. 5 shows the relationship between concentration (ppm) and electrical conductivity (μS / cm), and FIG. 6 shows the relationship between graphene oxide concentration (ppm) and pH.
［比較例１］
水処理用薬剤として、酸化グラフェン１を含有する水処理用薬剤の代わりに次亜塩素酸を用いた以外は、実施例１と同様にして、殺菌効果を確認した。次亜塩素酸は、被処理水中の全塩素濃度が１ｍｇ／Ｌとなるよう添加した。全塩素濃度は、ハンナインスツルメンツ社の残留塩素計ＨＩ９６７１１多項目水質分析計ＤＲ／４０００を用いて、全塩素測定法（ＤＰＤ（ジエチル−ｐ−フェニレンジアミン）法）により測定した値（ｍｇ／Ｌ ａｓＣｌ２）である。結果を表１に示す。
[Comparative Example 1]
The bactericidal effect was confirmed in the same manner as in Example 1 except that hypochlorous acid was used in place of the water treatment agent containing graphene oxide 1 as the water treatment agent. Hypochlorous acid was added so that the total chlorine concentration in the water to be treated was 1 mg / L. The total chlorine concentration is a value (mg / L asCl) measured by a total chlorine measurement method (DPD (diethyl-p-phenylenediamine) method) using a residual chlorine meter HI96711 multi-item water quality analyzer DR / 4000 of Hanna Instruments. 2 ). The results are shown in Table 1.
実施例の酸化グラフェンを含有する水処理用薬剤により、殺菌効果が得られることがわかった。比較例１の次亜塩素酸は、殺菌効果には優れるが、殺菌処理の後段の設備や材（逆浸透膜やイオン交換樹脂等）にダメージを与え、殺菌処理の後段の塩負荷が増加してしまうが、実施例の酸化グラフェンを含有する水処理用薬剤は次亜塩素酸よりも酸化剤としてはマイルドであり、後段の設備や材に対する酸化劣化の程度を抑制することができ、また、酸化グラフェンは精密ろ過膜（ＭＦ膜）等を用いたろ過等で除去することができるため、殺菌処理の後段の塩負荷の増加を抑制することができる。 It was found that the bactericidal effect was obtained by the water treatment chemical containing graphene oxide of the example. The hypochlorous acid of Comparative Example 1 is excellent in sterilization effect, but damages the equipment and materials (such as reverse osmosis membrane and ion exchange resin) at the later stage of the sterilization process, and increases the salt load at the later stage of the sterilization process. However, the water treatment agent containing graphene oxide of the example is milder as an oxidizing agent than hypochlorous acid, and can suppress the degree of oxidative deterioration of the subsequent equipment and materials, Since graphene oxide can be removed by filtration using a microfiltration membrane (MF membrane) or the like, an increase in salt load after the sterilization treatment can be suppressed.
以上の通り、酸化グラフェンを含有する新たな水処理用薬剤が得られ、酸化グラフェンを含有する水処理用薬剤を用いて、殺菌処理等の水処理が可能であることがわかった。 As described above, a new water treatment agent containing graphene oxide was obtained, and it was found that water treatment such as sterilization treatment was possible using the water treatment agent containing graphene oxide.
Claims (11)
前記酸化グラフェンの平面形状が、長手方向の大きさで０．１〜５０μｍの範囲であることを特徴とする水処理用薬剤。 The water treatment agent according to claim 1,
The water treatment agent, wherein the planar shape of the graphene oxide is in the range of 0.1 to 50 µm in the longitudinal direction.
前記酸化グラフェンの酸素含有量が、２５〜６５重量％の範囲であることを特徴とする水処理用薬剤。 The chemical for water treatment according to claim 1 or 2,
An oxygen content of the graphene oxide is in the range of 25 to 65% by weight.
前記酸化グラフェンのＸＰＳ分析において、Ｃ−Ｃピーク強度に対して、Ｃ−Ｏピーク強度およびＣ＝Ｏピーク強度の少なくとも１つが０．３倍以上であることを特徴とする水処理用薬剤。 The water treatment agent according to claim 3,
In the XPS analysis of the graphene oxide, at least one of the C—O peak intensity and the C═O peak intensity is 0.3 times or more with respect to the C—C peak intensity.
前記酸化グラフェンの厚さが、炭素原子１０層以下であることを特徴とする水処理用薬剤。 It is the chemical | medical agent for water treatment of any one of Claims 1-4,
The water treatment agent, wherein the graphene oxide has a thickness of 10 or less carbon atoms.
前記水処理用薬剤中の前記酸化グラフェンの含有量が、０．０１〜５０重量％の範囲であることを特徴とする水処理用薬剤。 It is the chemical | medical agent for water treatment of any one of Claims 1-5,
Content of the said graphene oxide in the said chemical | medical agent for water treatment is the range of 0.01 to 50 weight%, The chemical | medical agent for water treatment characterized by the above-mentioned.
前記水処理用薬剤のｐＨが、０〜８の範囲であることを特徴とする水処理用薬剤。 It is a chemical | medical agent for water treatment of any one of Claims 1-6,
The water treatment chemical, wherein the pH of the water treatment chemical is in the range of 0 to 8.
前記酸化グラフェンは、硫酸に黒鉛を加えて、過マンガン酸カリウムと５０℃以下で反応させたものであることを特徴とする水処理用薬剤。 It is the chemical | medical agent for water treatment of any one of Claims 1-7,
The water treatment agent, wherein the graphene oxide is obtained by adding graphite to sulfuric acid and reacting with potassium permanganate at 50 ° C. or lower.
前記殺菌処理における前記被処理水中の前記酸化グラフェンの濃度が、０．５〜５０ｍｇ／Ｌの範囲であることを特徴とする水処理方法。 The water treatment method according to claim 10,
The water treatment method, wherein a concentration of the graphene oxide in the water to be treated in the sterilization treatment is in a range of 0.5 to 50 mg / L.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103272560A (en) * | 2013-05-30 | 2013-09-04 | 河北工业大学 | Novel composite water treatment material and preparation method thereof |
| US20140263090A1 (en) * | 2013-03-15 | 2014-09-18 | Stephen A. Yencho | High Flow Rate Fluid Disinfection System |
| US20160038885A1 (en) * | 2014-08-08 | 2016-02-11 | University Of Southern California | High performance membranes for water reclamation using polymeric and nanomaterials |
| JP2017036191A (en) * | 2015-08-12 | 2017-02-16 | 株式会社東芝 | Graphene derivative and use thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
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| CN103272560A (en) * | 2013-05-30 | 2013-09-04 | 河北工业大学 | Novel composite water treatment material and preparation method thereof |
| US20160038885A1 (en) * | 2014-08-08 | 2016-02-11 | University Of Southern California | High performance membranes for water reclamation using polymeric and nanomaterials |
| JP2017036191A (en) * | 2015-08-12 | 2017-02-16 | 株式会社東芝 | Graphene derivative and use thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2022051556A (en) * | 2020-09-18 | 2022-03-31 | シーピーケイ インテリオール プロダクツ インコーポレイテッド | Graphene-based antiviral polymer |
| JP7333806B2 (en) | 2020-09-18 | 2023-08-25 | シーピーケイ インテリオール プロダクツ インコーポレイテッド | Graphene-based antiviral polymer |
| US11878635B2 (en) | 2020-09-18 | 2024-01-23 | Cpk Interior Products Inc. | Graphene-based antiviral polymer |
| US11807753B2 (en) | 2020-10-28 | 2023-11-07 | Cpk Interior Products Inc. | Thermoplastic polyolefin-based slush powder compositions |
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