JP6990815B2 - Hydrogen recombination catalyst - Google Patents
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- JP6990815B2 JP6990815B2 JP2017161867A JP2017161867A JP6990815B2 JP 6990815 B2 JP6990815 B2 JP 6990815B2 JP 2017161867 A JP2017161867 A JP 2017161867A JP 2017161867 A JP2017161867 A JP 2017161867A JP 6990815 B2 JP6990815 B2 JP 6990815B2
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- 239000003054 catalyst Substances 0.000 title claims description 61
- 239000001257 hydrogen Substances 0.000 title claims description 57
- 229910052739 hydrogen Inorganic materials 0.000 title claims description 57
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims description 47
- 230000006798 recombination Effects 0.000 title claims description 36
- 238000005215 recombination Methods 0.000 title claims description 36
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 77
- 239000000843 powder Substances 0.000 claims description 71
- 229920000876 geopolymer Polymers 0.000 claims description 48
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 39
- 229910052697 platinum Inorganic materials 0.000 claims description 36
- 229910052763 palladium Inorganic materials 0.000 claims description 17
- 229910010272 inorganic material Inorganic materials 0.000 claims description 10
- 239000011147 inorganic material Substances 0.000 claims description 10
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- 239000000243 solution Substances 0.000 description 20
- 230000003197 catalytic effect Effects 0.000 description 11
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- 239000001301 oxygen Substances 0.000 description 6
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- 230000007774 longterm Effects 0.000 description 5
- IXSUHTFXKKBBJP-UHFFFAOYSA-L azanide;platinum(2+);dinitrite Chemical compound [NH2-].[NH2-].[Pt+2].[O-]N=O.[O-]N=O IXSUHTFXKKBBJP-UHFFFAOYSA-L 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
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- NWAHZABTSDUXMJ-UHFFFAOYSA-N platinum(2+);dinitrate Chemical compound [Pt+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O NWAHZABTSDUXMJ-UHFFFAOYSA-N 0.000 description 4
- 235000019353 potassium silicate Nutrition 0.000 description 4
- 230000002285 radioactive effect Effects 0.000 description 4
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- NNHHDJVEYQHLHG-UHFFFAOYSA-N potassium silicate Chemical compound [K+].[K+].[O-][Si]([O-])=O NNHHDJVEYQHLHG-UHFFFAOYSA-N 0.000 description 3
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- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
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- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 2
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- 239000002861 polymer material Substances 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
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- XHCLAFWTIXFWPH-UHFFFAOYSA-N [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[V+5].[V+5] XHCLAFWTIXFWPH-UHFFFAOYSA-N 0.000 description 1
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- INAHAJYZKVIDIZ-UHFFFAOYSA-N boron carbide Chemical compound B12B3B4C32B41 INAHAJYZKVIDIZ-UHFFFAOYSA-N 0.000 description 1
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- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
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- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
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- MHOVAHRLVXNVSD-UHFFFAOYSA-N rhodium atom Chemical compound [Rh] MHOVAHRLVXNVSD-UHFFFAOYSA-N 0.000 description 1
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- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
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Description
本発明は、含水放射性廃棄物の保管時に発生する水素の濃度を低減させるために用いられる、水素再結合触媒に関する。 The present invention relates to a hydrogen recombination catalyst used to reduce the concentration of hydrogen generated during storage of hydrous radioactive waste.
現在、福島第一原子力発電所では、廃炉に向けて、原子炉建屋等の汚染水から放射性セシウムを除去するための処理が行われている。この処理において、汚染水中に含まれる放射性セシウムは吸着塔により除去されるが、使用済みの吸着塔は放射能濃度が低下するまで長期保管されることになる。そして、この長期保管時において、吸着塔内に残留する水分が放射線により水素と酸素に分解され、保管容器内に蓄積した水素が放射性セシウムの崩壊熱による温度上昇によって引火爆発する虞があった。そこで、現在、保管容器の弁を開放し、保管容器内で発生した水素ガスが保管容器内に留まらないようにしている。しかし、この方法では放射性物質が環境中に放出される危険性があった。 Currently, at the Fukushima Daiichi Nuclear Power Station, treatment is being carried out to remove radioactive cesium from contaminated water in the reactor building, etc. toward decommissioning. In this treatment, radioactive cesium contained in the contaminated water is removed by the adsorption tower, but the used adsorption tower will be stored for a long time until the radioactive concentration decreases. During this long-term storage, the water remaining in the adsorption tower is decomposed into hydrogen and oxygen by radiation, and the hydrogen accumulated in the storage container may ignite and explode due to the temperature rise due to the decay heat of radioactive cesium. Therefore, at present, the valve of the storage container is opened so that the hydrogen gas generated in the storage container does not stay in the storage container. However, with this method, there was a risk that radioactive substances would be released into the environment.
このため、水素再結合触媒を備えた静的触媒式水素再結合容器を用いて、発生した水素と酸素を再結合させることが検討されている。なお、米国では、スリーマイル島原発２号機の事故で発生した燃料デブリの保管の際に、一部、白金からなる水素再結合触媒が用いらているが、国内ではまだ用いられていない。この水素再結合触媒には、大量の汚染水を処理するために大量の水素結合触媒が必要とされることから、大量生産可能であって安価であるとともに、長期安定性に優れているという特性が要求されている。 Therefore, it has been studied to recombinate generated hydrogen and oxygen by using a static catalytic hydrogen recombination vessel equipped with a hydrogen recombination catalyst. In the United States, a hydrogen recombination catalyst made of platinum is partially used for storage of fuel debris generated in the accident at Three Mile Island Nuclear Generating Unit 2, but it has not been used in Japan yet. Since this hydrogen rebonding catalyst requires a large amount of hydrogen bonding catalyst to treat a large amount of contaminated water, it can be mass-produced, is inexpensive, and has excellent long-term stability. Is required.
ところで、ジオポリマーは、アルミノケイ酸塩を基とした非晶質の無機高分子材料であり、組成の柔軟性、耐熱性、化学的安定性、耐放射線性などの優れた性質を有している。緻密で強度もあることから、構造材料の分野では、セメントの代わりとなる材料として注目されている（例えば、特許文献１、２）。また、ジオポリマーは、活性フィラーとしてのアルミナシリカ粉末と、アルカリシリカ溶液から製造される。アルミナシリカ粉末とアルカリシリカ溶液とを混合し養生すると重合反応が進み、固化することでジオポリマーが得られる。なお、原料のアルミナシリカ粉末には、フライアッシュや高炉スラグを用いることができる。
By the way, geopolymer is an amorphous inorganic polymer material based on aluminosilicate, and has excellent properties such as composition flexibility, heat resistance, chemical stability, and radiation resistance. .. Since it is dense and strong, it is attracting attention as a substitute material for cement in the field of structural materials (for example,
したがって、ジオポリマーを水素再結合触媒の担持材料として用いることができれば、大量生産可能であって安価であるとともに、長期安定性に優れた水素結合触媒が得られるものと考えられた（非特許文件１）。 Therefore, if a geopolymer can be used as a supporting material for a hydrogen rebinding catalyst, it is considered that a hydrogen bonding catalyst that can be mass-produced, is inexpensive, and has excellent long-term stability can be obtained (non-patent statement). 1).
ジオポリマーを水素再結合触媒の担持材料として用いる場合、触媒として用いられる高価な貴金属を効率よく使用して水素再結合能力を高めるために、ジオポリマーの比表面積を大きくすることが望ましい。そこで、比表面積を大きくするためには、ジオポリマーをハニカム構造体や多孔質体にすることが考えられた（非特許文献２）。しかし、構造材料として注目されるほど強度の高いジオポリマーであっても、ハニカム構造体や多孔質体にすると強度の低下は避けられない。 When the geopolymer is used as a supporting material for the hydrogen recombination catalyst, it is desirable to increase the specific surface area of the geopolymer in order to efficiently use the expensive noble metal used as the catalyst and increase the hydrogen recombination ability. Therefore, in order to increase the specific surface area, it was considered to make the geopolymer into a honeycomb structure or a porous body (Non-Patent Document 2). However, even if the geopolymer has a high strength enough to attract attention as a structural material, a decrease in strength is unavoidable when a honeycomb structure or a porous body is used.
一方、水素再結合触媒を取り扱う作業においては、作業者を放射線から防護するために、遠隔操作ロボットを用いたり、人手を介する場合においては作業を短時間で終わらせる必要があり、水素再結合触媒の取り扱いは粗雑になりやすい。このため、水素結合触媒は、粗雑な取り扱いに耐えられる一定以上の強度が要求される。 On the other hand, in the work of handling the hydrogen recombination catalyst, in order to protect the worker from radiation, it is necessary to use a remote-controlled robot or, in the case of manual intervention, to complete the work in a short time, and the hydrogen recombination catalyst. Handling tends to be crude. Therefore, the hydrogen bond catalyst is required to have a certain strength or higher that can withstand rough handling.
そこで、本発明は、ジオポリマーを含む無機材料を担持材料として用い、十分な強度と高い水素再結合能力とを有する、新規の水素再結合触媒を提供することを目的とする。 Therefore, an object of the present invention is to provide a novel hydrogen recombination catalyst having sufficient strength and high hydrogen recombination ability by using an inorganic material containing a geopolymer as a supporting material.
本発明の水素再結合触媒は、ジオポリマーを含む無機材料からなる担体と、この担体の表面に担持された無機粉末と、この無機粉末の表面に担持された触媒とからなることを特徴とする。 The hydrogen recombination catalyst of the present invention is characterized by comprising a carrier made of an inorganic material containing a geopolymer, an inorganic powder supported on the surface of the carrier, and a catalyst supported on the surface of the inorganic powder. ..
また、平均直径３～５０ｍｍの略球形状であることを特徴とする。 Further, it is characterized by having a substantially spherical shape having an average diameter of 3 to 50 mm.
また、前記無機粉末は、比表面積が４０～２００ｍ２／ｇであることを特徴とする。 Further, the inorganic powder is characterized by having a specific surface area of 40 to 200 m 2 / g.
また、前記無機粉末は、γアルミナ粉末であることを特徴とする。 Further, the inorganic powder is characterized by being a γ-alumina powder.
また、前記触媒は、白金又はパラジウムからなることを特徴とする。 Further, the catalyst is characterized by being made of platinum or palladium.
また、前記触媒は、白金又はパラジウムを含み、白金、パラジウム、又は白金とパラジウムの合計が３０質量％以上であることを特徴とする。 Further, the catalyst contains platinum or palladium, and the total amount of platinum, palladium, or platinum and palladium is 30% by mass or more.
本発明によれば、強度の高いジオポリマーを含む無機材料を担体とすることによって十分な強度を有するとともに、大きい比表面積をもつ無機粉末の表面に触媒を担持させることによって高い水素再結合能力を有する水素再結合触媒が提供される。 According to the present invention, an inorganic material containing a high-strength geopolymer is used as a carrier to have sufficient strength, and a catalyst is supported on the surface of an inorganic powder having a large specific surface area to obtain high hydrogen recombination ability. A hydrogen recombination catalyst having is provided.
本発明の水素再結合触媒は、図１に模式的に示すように、ジオポリマーを含む無機材料を担持材料としている。なお、ａは担持材料がジオポリマーのみからなるもの、ｂはジオポリマー中にジオポリマー以外の無機の骨材が存在するもの、ｃはジオポリマー以外の無機の球状体からなる中心核を有しジオポリマー層を表層に形成したものを示す。 As schematically shown in FIG. 1, the hydrogen recombination catalyst of the present invention uses an inorganic material containing a geopolymer as a supporting material. In addition, a has a support material made of only a geopolymer, b has an inorganic aggregate other than the geopolymer in the geopolymer, and c has a central core made of an inorganic sphere other than the geopolymer. The one in which the geopolymer layer was formed on the surface layer is shown.
担持材料のジオポリマーは、ゼオライトに類似した非晶質構造を有する無機高分子材料であり、ＳｉＯ４四面体及びＡｌＯ４四面体が酸素原子を介して３次元的に連結し、チャージバランスを保つため構造中に陽イオンを取り込んでいる。その硬化反応式は以下に示すようなものであるとされている。 The geopolymer of the supporting material is an inorganic polymer material having an amorphous structure similar to zeolite, and the SiO4 tetrahedron and AlO4 tetrahedron are three-dimensionally connected via oxygen atoms to maintain charge balance. Therefore, cations are incorporated into the structure. The curing reaction formula is said to be as shown below.
本発明の水素再結合触媒を構成するジオポリマーを含む無機材料からなる担体は、高い強度を確保するためと製造の容易さから中実であることが好ましいが、強度を確保できれば、無機材料からなる骨材を含むことや、中空であってもよい、また、中心核に他の無機材料からなる球状体を使用することを妨げるものではない。また、担体の形状は限定されないが、取り扱いの容易さから略球形であることが好ましい。担体の大きさは限定されないが、実用上、保管容器への投入や触媒の保持を考慮すると、直径３～５０ｍｍが望ましい。 The carrier made of an inorganic material containing the geopolymer constituting the hydrogen recombination catalyst of the present invention is preferably solid in order to secure high strength and easy to manufacture, but if the strength can be ensured, the carrier made of the inorganic material is used. It does not preclude the inclusion of an aggregate, which may be hollow, and the use of spheres of other inorganic materials for the core. Further, the shape of the carrier is not limited, but it is preferably substantially spherical from the viewpoint of ease of handling. The size of the carrier is not limited, but practically, a diameter of 3 to 50 mm is desirable in consideration of loading into a storage container and holding of the catalyst.
そして、このジオポリマーを含む無機材料の表面にアルミナ粉末などの無機粉末が担持され、さらにこの無機粉末の表面に白金やパラジウムなどの触媒が担持された構造を有している。この構造により、水素再結合触媒の高い強度と大きい比表面積が確保され、その結果として高い触媒性能が得られるようになっている。 Further, it has a structure in which an inorganic powder such as alumina powder is supported on the surface of the inorganic material containing the geopolymer, and a catalyst such as platinum or palladium is supported on the surface of the inorganic powder. This structure ensures high strength and a large specific surface area of the hydrogen recombination catalyst, resulting in high catalytic performance.
本発明の水素再結合触媒を構成する無機粉末としては、例えば、アルミナ粉末、シリカ粉末、ジルコニア粉末、セリア粉末、酸化チタン粉末などの金属酸化物粉末、炭化ケイ素、炭化ホウ素などの金属炭化物粉末、窒化ケイ素、窒化ホウ素などの金属窒化物粉末が挙げられる。これらの中では、安価であって、化学的に安定、入手可能な粒径の種類が多い、ジオポリマーの原料の一種であり担体のジオポリマーとなじみやすい、などの理由から、アルミナ粉末が好適に用いられ、アルミナ粉末の中でも比表面積の大きいγアルミナ粉末がより好適に用いられる。無機粉末の粒径は、ジオポリマーとの結合（接着）力が強くなる数十～数百μｍが好ましく、入手可能な範囲では４０～２００μｍであることが好ましい。また、無機粉末の比表面積は、比表面積が大きい方が白金が分散し白金自体の粒径が小さくなり、白金の表面積も大きくなるため、大きければ大きい方が良いが、入手可能な範囲では４０～２００ｍ２／ｇであることが好ましい。 Examples of the inorganic powder constituting the hydrogen recombination catalyst of the present invention include metal oxide powders such as alumina powder, silica powder, zirconia powder, ceria powder and titanium oxide powder, and metal carbide powders such as silicon carbide and boron carbide. Examples thereof include metal nitride powders such as silicon nitride and boron nitride. Among these, alumina powder is preferable because it is inexpensive, chemically stable, has many types of particle sizes available, and is a kind of raw material for geopolymers and is easily compatible with the geopolymer of the carrier. Among the alumina powders, γ-alumina powder having a large specific surface area is more preferably used. The particle size of the inorganic powder is preferably several tens to several hundreds μm, which strengthens the bonding (adhesive) force with the geopolymer, and is preferably 40 to 200 μm within the available range. Further, as for the specific surface area of the inorganic powder, the larger the specific surface area, the more platinum is dispersed and the particle size of platinum itself becomes smaller, and the surface area of platinum also becomes larger. Therefore, the larger the specific surface area, the better. It is preferably about 200 m 2 / g.
本発明の水素再結合触媒を構成する触媒としては、例えば、白金、パラジウム、ロジウム、ルテニウムなどの貴金属、酸化チタン、酸化銅、酸化亜鉛、酸化ニッケル、酸化バナジウムなどの金属酸化物、からなるものとすることができる。これらの中では、水素再結合能力の高さから、白金又はパラジウムからなる触媒が好適に用いられる。さらに、本発明の水素再結合触媒を構成する触媒は、白金、パラジウム、又は白金とパラジウムの合計が３０質量％以上であることが望ましい。 The catalyst constituting the hydrogen recombination catalyst of the present invention includes, for example, precious metals such as platinum, palladium, rhodium and ruthenium, and metal oxides such as titanium oxide, copper oxide, zinc oxide, nickel oxide and vanadium oxide. Can be. Among these, a catalyst made of platinum or palladium is preferably used because of its high hydrogen recombination ability. Further, it is desirable that the catalyst constituting the hydrogen recombination catalyst of the present invention has platinum, palladium, or a total of platinum and palladium of 30% by mass or more.
以上のように、本発明の水素再結合触媒は、強度の高いジオポリマーを含む無機材料を担持材料とすることによって十分な強度を有するとともに、大きい比表面積をもつ無機粉末の表面に触媒を担持させることによって高い水素再結合能力を有する。本発明の水素再結合触媒を含水性放射性廃棄物を貯蔵する保管容器内に設置することにより、水の放射線分解により発生した水素と酸素を再結合させ、水に戻すことにより容器内の水素濃度の上昇を抑制することができる。 As described above, the hydrogen recombination catalyst of the present invention has sufficient strength by using an inorganic material containing a high-strength geopolymer as a supporting material, and supports the catalyst on the surface of an inorganic powder having a large specific surface area. It has a high hydrogen recombination ability by making it. By installing the hydrogen recombination catalyst of the present invention in a storage container for storing water-containing radioactive waste, hydrogen and oxygen generated by radiolysis of water are recombined and returned to water to concentrate the hydrogen in the container. Can be suppressed from rising.
本発明の水素再結合触媒は、例えば、以下の手順で得ることができる。 The hydrogen recombination catalyst of the present invention can be obtained, for example, by the following procedure.
はじめに、触媒が担持された無機粉末を作製する。なお、触媒が担持された無機粉末は、無機粉末や触媒の種類に応じて、公知の方法によって作製することができる。 First, an inorganic powder on which a catalyst is supported is prepared. The inorganic powder on which the catalyst is supported can be produced by a known method depending on the type of the inorganic powder or the catalyst.
つぎに、ジオポリマーの原料である、活性フィラーとしてのアルミナシリカ粉末と、アルカリシリカ溶液を混合して、ジオポリマー溶液を作製する。アルミナシリカ粉末には、メタカオリンとマイクロシリカ（シリカフューム）を混合したものが好適に用いられる。マイクロシリカの代わりに、二酸化ケイ素を含有するフライアッシュ、高炉スラグ、下水汚泥などを用いてもよい。また、アルカリシリカ溶液には、ケイ酸カリウム溶液、水酸化カリウム、水を混合したものが好適に用いられる。ケイ酸カリウム溶液の代わりにケイ酸ナトリウム溶液（水ガラス）を用いてもよく、水酸化カリウムの代わりに水酸化ナトリウムを用いてもよい。 Next, the alumina silica powder as an active filler, which is a raw material of the geopolymer, and the alkaline silica solution are mixed to prepare a geopolymer solution. As the alumina silica powder, a mixture of metakaolin and microsilica (silica fume) is preferably used. Instead of microsilica, fly ash containing silicon dioxide, blast furnace slag, sewage sludge, or the like may be used. Further, as the alkali silica solution, a mixture of potassium silicate solution, potassium hydroxide and water is preferably used. A sodium silicate solution (water glass) may be used instead of the potassium silicate solution, and sodium hydroxide may be used instead of potassium hydroxide.
そして、このジオポリマー溶液を型に流し込んで養生し、表面が完全に固化していないジオポリマーを型から取り出す。養生の条件は、例えば、７０～９０℃で２０～５０分間とするのが好ましい。 Then, this geopolymer solution is poured into a mold and cured, and the geopolymer whose surface is not completely solidified is taken out from the mold. The curing conditions are preferably, for example, 70 to 90 ° C. for 20 to 50 minutes.
そして、このジオポリマーの表面に、触媒が担持された無機粉末を付着させることにより、ジオポリマーの表面に触媒が担持された無機粉末をコーティングする。 Then, the catalyst-supported inorganic powder is coated on the surface of the geopolymer by adhering the catalyst-supported inorganic powder to the surface of the geopolymer.
その後、養生して、ジオポリマーを完全に固化させる。養生の条件は、例えば、７０～９０℃で１～３日間とするのが好ましい。 It is then cured to completely solidify the geopolymer. The curing conditions are preferably, for example, 70 to 90 ° C. for 1 to 3 days.
または、同様の手順で、ジオポリマーの表面に、触媒が担持されていない無機粉末を付着させ、コーティングと養生を行った後に、触媒を担持させてもよい。 Alternatively, the catalyst may be supported on the surface of the geopolymer in the same procedure after the inorganic powder on which the catalyst is not supported is attached and coated and cured.
以上の手順により、本発明の水素再結合触媒を得ることができる。 By the above procedure, the hydrogen recombination catalyst of the present invention can be obtained.
以下、本発明の水素再結合触媒について具体的に説明する。なお、本発明は以下の実施例に限定されるものではなく、種々の変形実施が可能である。 Hereinafter, the hydrogen recombination catalyst of the present invention will be specifically described. The present invention is not limited to the following examples, and various modifications can be carried out.
［アルミナ粉末への白金の担持］
アルミナ粉末を白金硝酸塩溶液中に浸漬して白金硝酸塩溶液と混合し、その後、乾燥させて大気中で焼成することで、表面に白金を担持させたアルミナ粉末を作製した。白金材料として、ジニトロジアンミン白金（II）硝酸溶液（Ｐｔ（ＮＨ３）２（ＮＯ２）２／ＨＮＯ３）を用いた。白金を担持するアルミナ粉末として、比表面積の大きなγアルミナ粉末を用いた。比較のため、白金を担持させるアルミナ粉末を３種類準備した。それぞれのアルミナ粉末の物性は、表１に示すとおりであった。
[Supporting platinum on alumina powder]
Alumina powder was immersed in a platinum nitrate solution, mixed with the platinum nitrate solution, then dried and calcined in the air to prepare an alumina powder having platinum supported on its surface. As a platinum material, a dinitrodiammine platinum (II) nitric acid solution (Pt (NH 3 ) 2 (NO 2 ) 2 / HNO 3 ) was used. As the alumina powder supporting platinum, γ-alumina powder having a large specific surface area was used. For comparison, three types of alumina powder supporting platinum were prepared. The physical characteristics of each alumina powder are as shown in Table 1.
図２に示すように、使用するアルミナ粉末に対して白金が０．１～１質量％となるように水で希釈したジニトロジアンミン白金（II）硝酸溶液を準備し、アルミナ粉末をこの白金硝酸塩溶液中に浸漬した。そして、分散媒にエタノールを用い、アルミナ粉末と白金硝酸塩水溶液を、回転数５２０回／分のボールミルにより１０分間混合した。混合した試料を乾燥機により９０℃で４時間乾燥させた後、粉砕し、大気雰囲気で５００℃で３時間焼成することにより、白金を担持させたアルミナ粉末を得た。 As shown in FIG. 2, a dinitrodiammine platinum (II) nitric acid solution diluted with water so that platinum is 0.1 to 1% by mass with respect to the alumina powder to be used is prepared, and the alumina powder is used as this platinum nitrate solution. Soaked in. Then, ethanol was used as the dispersion medium, and the alumina powder and the platinum nitrate aqueous solution were mixed for 10 minutes by a ball mill at a rotation speed of 520 times / min. The mixed sample was dried at 90 ° C. for 4 hours by a dryer, pulverized, and calcined at 500 ° C. for 3 hours in an air atmosphere to obtain an alumina powder carrying platinum.
［白金担持アルミナ粉末のジオポリマー担体への担持］
略球形のジオポリマー担体を作製し、その表面に、白金を担持したアルミナ粉末をコーティングした。ジオポリマー担体の原料の配合割合を表２に示す。コーティングは、ジオポリマー担体の養生中であってジオポリマーが完全に固化する前に、ジオポリマー担体の表面にアルミナ粉末を付着させることにより行った。
[Supporting platinum-supported alumina powder on a geopolymer carrier]
A substantially spherical geopolymer carrier was prepared, and the surface thereof was coated with an alumina powder carrying platinum. Table 2 shows the mixing ratio of the raw materials of the geopolymer carrier. The coating was performed by adhering alumina powder to the surface of the geopolymer carrier during curing of the geopolymer carrier and before the geopolymer was completely solidified.
図３に示すように、ケイ酸カリウム、純水、水酸化カリウム、マイクロシリカ、メタカオリンを表２に示す配合比率で配合、混合してジオポリマー溶液を作製し、このジオポリマー溶液を略球形の型に流し込んだ。７０℃で２０～５０分間養生した後、表面が完全に固化していないジオポリマーを型から取り出し、このジオポリマーの表面に白金担持アルミナ粉末を付着させることにより、ジオポリマーの表面に白金担持アルミナ粉末をコーティングした。その後、７０℃で１～３日間養生して、ジオポリマーを完全に固化させ、白金担持アルミナ粉末を担持させたジオポリマー担体、すなわち、本発明の水素再結合触媒を得た。実際に得られた本発明の水素再結合触媒の外観を図４に示す。 As shown in FIG. 3, potassium silicate, pure water, potassium hydroxide, microsilica, and metacaolin are blended and mixed at the blending ratios shown in Table 2 to prepare a geopolymer solution, and the geopolymer solution is substantially spherical. I poured it into a mold. After curing at 70 ° C. for 20 to 50 minutes, the geopolymer whose surface is not completely solidified is removed from the mold, and platinum-supported alumina powder is adhered to the surface of the geopolymer, whereby platinum-supported alumina is attached to the surface of the geopolymer. The powder was coated. Then, it was cured at 70 ° C. for 1 to 3 days to completely solidify the geopolymer, and a geopolymer carrier carrying platinum-supported alumina powder, that is, the hydrogen recombination catalyst of the present invention was obtained. The appearance of the hydrogen recombination catalyst of the present invention actually obtained is shown in FIG.
［電子顕微鏡観察］
透過型電子顕微鏡（ＴＥＭ）を用いて、表面に白金を担持したアルミナ粉末の観察を行った。得られたＴＥＭ像を図５に示す。また、表面に白金を担持したアルミナ粉末の電子線回折を行った。そして、得られた電子線回折像から半径を測り、半径の逆数から面間隔であるｄ値を求め、白金の化学状態の同定を行った。電子線回折像を図６に、得られたｄ値、アルミナのカードデータ、白金のカードデータを、それぞれ表３、表４、表５に示す。その結果、電子線回析像から白金の（２００）面に対応するｄ値が得られ、金属の白金が存在していることが確認された。
[Electron microscope observation]
Using a transmission electron microscope (TEM), the alumina powder supporting platinum on the surface was observed. The obtained TEM image is shown in FIG. In addition, electron diffraction of alumina powder supporting platinum on the surface was performed. Then, the radius was measured from the obtained electron diffraction image, the d value, which is the surface spacing, was obtained from the reciprocal of the radius, and the chemical state of platinum was identified. The electron diffraction image is shown in FIG. 6, and the obtained d value, the alumina card data, and the platinum card data are shown in Tables 3, 4, and 5, respectively. As a result, the d value corresponding to the (200) plane of platinum was obtained from the electron beam diffraction image, and it was confirmed that the metallic platinum was present.
［触媒性能の評価］
実施例１で得られた表面に白金を担持したアルミナ粉末について、触媒性能の評価を行った。評価条件は、以下のとおりであった。
サンプル量：２５０ｍｇ
ガス組成：１．０％－Ｈ２、１．０％－Ｏ２、残り－Ａｒ
ガス流量：５０ｃｃ／分（総量）
昇温速度：１０℃／分
図７に、表面に白金を担持したアルミナ粉末の触媒性能の評価結果を示す（◆、■、×）。水素を酸素と結合させた割合を示す水素転化率が高い値を示し、水素再結合触媒として良好な触媒性能を持つことが示された。
[Evaluation of catalyst performance]
The catalytic performance of the alumina powder obtained in Example 1 in which platinum was supported on the surface was evaluated. The evaluation conditions were as follows.
Sample amount: 250 mg
Gas composition: 1.0% -H 2 , 1.0% -O 2 , remaining -Ar
Gas flow rate: 50cc / min (total amount)
Temperature rise rate: 10 ° C./min Figure 7 shows the evaluation results of the catalytic performance of the alumina powder carrying platinum on the surface (◆, ■, ×). The hydrogen conversion rate, which indicates the ratio of hydrogen bonded to oxygen, was high, indicating that it has good catalytic performance as a hydrogen recombination catalyst.
［アルミナ粉末へのパラジウムの担持］
ジニトロジアンミン白金（II）硝酸溶液（Ｐｔ（ＮＨ３）２（ＮＯ２）２/ＨＮＯ３）の代わりにジニトロジアンミンパラジウム（II）硝酸溶液（Ｐｄ（ＮＨ３）２（ＮＯ２）２/ＨＮＯ３）を用い、使用するアルミナ粉末に対してパラジウムが０．１質量％となるようにし、焼成温度を５５０℃としたほかは実施例１と同様にして、表面にパラジウムを担持させたアルミナ粉末を作製した。
[Supporting palladium on alumina powder]
Dinitrodiammine Palladium (II) Nitric Acid Solution (Pd (NH 3 ) 2 (NO 2 ) 2 / HNO 3 ) Instead of Dinitrodiammine Platinum (II) Nitric Acid Solution (Pt (NH 3 ) 2 (NO 2 ) 2 / HNO 3 ) ) Was used to make the amount of palladium 0.1% by mass with respect to the alumina powder used, and the firing temperature was set to 550 ° C. Made.
［触媒性能の評価］
実施例３で得られた表面にパラジウムを担持したアルミナ粉末について、触媒性能の評価を行った。評価条件は、実施例２と同様とした。
[Evaluation of catalyst performance]
The catalytic performance of the alumina powder obtained in Example 3 on which palladium was supported on the surface was evaluated. The evaluation conditions were the same as in Example 2.
図７に、表面にパラジウムを担持したアルミナ粉末の触媒性能の評価結果を示す（▲、＋）。水素を酸素と結合させた割合を示す水素転化率が高い値を示し、水素再結合触媒として良好な触媒性能を持つことが示された。 FIG. 7 shows the evaluation results of the catalytic performance of the alumina powder supporting palladium on the surface (▲, +). The hydrogen conversion rate, which indicates the ratio of hydrogen bonded to oxygen, was high, indicating that it has good catalytic performance as a hydrogen recombination catalyst.
［アルミナ粉末への白金とパラジウムの担持］
ジニトロジアンミン白金（II）硝酸溶液（Ｐｔ（ＮＨ３）２（ＮＯ２）２/ＨＮＯ３）とジニトロジアンミンパラジウム（II）硝酸溶液（Ｐｄ（ＮＨ３）２（ＮＯ２）２/ＨＮＯ３）の両方を用い、使用するアルミナ粉末に対して白金とパラジウムの合計が０．１質量％となるようにし、焼成温度を５５０℃としたほかは実施例１と同様にして、表面に白金とパラジウムを担持させたアルミナ粉末を作製した。
[Support of platinum and palladium on alumina powder]
Dinitrodiammine platinum (II) nitric acid solution (Pt (NH 3 ) 2 (NO 2 ) 2 / HNO 3 ) and dinitrodiammine palladium (II) nitric acid solution (Pd (NH 3 ) 2 (NO 2 ) 2 / HNO 3 ) Using both, platinum and palladium were applied to the surface in the same manner as in Example 1 except that the total of platinum and palladium was 0.1% by mass with respect to the alumina powder used and the firing temperature was 550 ° C. A supported alumina powder was prepared.
［触媒性能の評価］
実施例５で得られた表面に白金とパラジウムを担持したアルミナ粉末について、触媒性能の評価を行った。評価条件は、実施例２と同様とした。
[Evaluation of catalyst performance]
The catalytic performance of the alumina powder obtained in Example 5 on which platinum and palladium were supported was evaluated. The evaluation conditions were the same as in Example 2.
図７に、表面に白金とパラジウムを担持したアルミナ粉末の触媒性能の評価結果を示す（●）。水素を酸素と結合させた割合を示す水素転化率が高い値を示し、水素再結合触媒として良好な触媒性能を持つことが示された。 FIG. 7 shows the evaluation results of the catalytic performance of the alumina powder supporting platinum and palladium on the surface (●). The hydrogen conversion rate, which indicates the ratio of hydrogen bonded to oxygen, was high, indicating that it has good catalytic performance as a hydrogen recombination catalyst.
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| JP2011500494A (en) | 2007-10-18 | 2011-01-06 | コミッサリア ア ロンネルジー アトミック エ オ ゾンネルジー ザルテルナティーフ | Process for the preparation of geopolymers with controlled porosity, the resulting geopolymers and their various uses |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008543701A (en) | 2005-05-09 | 2008-12-04 | コーニング インコーポレイテッド | Geopolymer composite and structure formed therefrom |
| JP2011500494A (en) | 2007-10-18 | 2011-01-06 | コミッサリア ア ロンネルジー アトミック エ オ ゾンネルジー ザルテルナティーフ | Process for the preparation of geopolymers with controlled porosity, the resulting geopolymers and their various uses |
| JP2011230064A (en) | 2010-04-28 | 2011-11-17 | Hitachi-Ge Nuclear Energy Ltd | Hydrogen and oxygen recombination catalyst, recombination apparatus, and nuclear plant |
Non-Patent Citations (1)
| Title |
|---|
| 放射性廃棄物、容器内で長期安全保管 長岡技科大など研究，日本経済新聞，日本経済新聞社，2017年02月11日，https://www.nikkei.com/article/dgxlasfb10H10_q7a210c1l21000/，[online],[令和３年４月２７日検索] |
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