レドックス活性金属有機フレームワークによるCl2とBr2の可逆捕獲と放出
Yuri Tulchinsky1, Christopher H Hendon1, Kirill A Lomachenko2,3
1Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|March 29, 2017
まとめ
この研究は,塩素やブロミンなどの有毒な元素ハロゲンを安全に貯蔵し放出するための新しい金属有機フレームワーク (MOF) を提示しています. この材料は,再酸化メカニズムを使用して,これらの危険な化学物質を反転的に吸収し,放出し,産業の安全性を高めます.
科学分野:
- 材料科学
- 無機化学
- 化学工学
背景:
- 塩素とブロムは非常に有毒で腐食性があり,揮発性があり,貯蔵と輸送に重大な課題があります.
- これらのハロゲンを扱う現在の方法は不十分であり,より安全な代替品の開発が必要である.
- メタル・オーガニック・フレームワーク (MOF) は,調節可能な構造と高い表面積により,化学品の貯蔵のための固体材料としての可能性を秘めています.
研究 の 目的:
- 塩素とブロムの安全な貯蔵とオンデマンドの放出のための堅固な固体材料を開発する.
- コバルトベースのアゾラートMOFの可逆ハロゲン捕獲と放出のための使用を調査する.
- 有害なハロゲンの化学貯蔵と熱的放出のためのリドックス駆動メカニズムを実証する.
主な方法:
- 協調的に不飽和のCO2イオンを含む堅固なアゾラート金属有機フレーム (MOF) の合成
- 塩素とブロムによるCo (II) からCo (III) の定量的酸化により,安定したCo (III) -ハロゲン結合が形成される.
- 熱処理により,Co (III) -ハロゲン結合の同解分裂を誘導し,元素ハロゲンを放出し,Co (II) を再生する.
- MOFの構造的整合性,結晶性,および多孔性の評価
主要な成果:
- 元素ハロゲンは,MOFで定量的に酸化したCo (II) イオンを,末端のCo (III) -ハロゲン結合を持つ安定したCo (III) 種に変換する.
- 熱処理は,Co (III) -ハロゲン結合の割れとCo (II) 再生によって元素ハロゲンを成功裏に放出しました.
- MOFは優れた再利用性を示し,3つの酸化減少サイクルにわたって構造と多孔性を保持しました.
- この材料は,元素ハロゲンの可逆化学貯蔵と熱的放出に有効であることが証明された.
結論:
- コバルト基の新しいMOFは,塩素とブロムの安全で可逆的な貯蔵とオンデマンドの放出を可能にします.
- 材料は,Co (II) /Co (III) 変換とハロゲン結合を含むリドックスメカニズムで動作する.
- このMOF技術は,化学産業における安全性の向上と,他の危険なガスの捕獲に有望な解決策を提供します.
関連する概念動画
Extraction: Advanced Methods
1.2K
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
1.2K
Oxidation-Reduction Reactions
76.4K
Oxidation–Reduction Reactions
76.4K
Metal-Ligand Bonds
25.1K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
25.1K
Redox Reactions
59.2K
Oxidation-reduction or redox reactions involve the transfer of electrons from one molecule or atom to another. When an atom gains an electron, another atom must lose an electron, meaning oxidation and reduction must occur together. Since the redox occurs in pairs, the atom that gets oxidized is also called the reducing agent or reductant, and the atom that is reduced is also called the oxidizing agent or oxidant. A straightforward way to remember the definitions of oxidation and reduction is...
59.2K
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
12.2K
Chlorination and bromination are important classes of electrophilic aromatic substitutions, where benzene reacts with chlorine or bromine in the presence of a Lewis acid catalyst to give halogenated substitution products. A Lewis acid such as aluminium chloride or ferric chloride catalyzes the chlorination, and ferric bromide catalyzes the bromination reactions. During the bromination of alkenes, bromine polarizes and becomes electrophilic. However, in the bromination of benzene, the bromine...
12.2K
Ionic Bonding and Electron Transfer
51.9K
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
51.9K


