エチレンオリゴメリゼーションのためのメタルロセンの触媒の活性と選択性に対する微孔構造内の閉じ込めの影響に関する計算による研究
Hervé Toulhoat1, Mireille Lontsi Fomena, Theodorus de Bruin
1Direction Scientifique, IFP Energies nouvelles, Rueil-Malmaison, France. herve.toulhoat@ifpenergiesnouvelles.fr
Journal of the American Chemical Society
|February 10, 2011
まとめ
ゼオライトに閉じ込められることは,エチレンオリゴメリゼーションのためのメタルロゼン触媒の性能を変化させます. シミュレーションにより,毛穴のサイズが活性と選択性に影響を及ぼすことが明らかになり,アルファオクテンのような特定の製品の収穫量を最適化することができます.
科学分野:
- 異質なカタリシス
- 材料科学 材料科学とは
- コンピューティング・ケミストリー
背景:
- メタロセンの触媒は,エチレンオリゴメリゼーションに不可欠です.
- ゼオリック構造は,触媒反応のための調整可能な環境を提供します.
- 閉じ込め効果を理解することは,触媒設計の鍵です.
研究 の 目的:
- ゼオライトの閉じ込めがメタルロセンの触媒の活性と選択性に与える影響を調査する.
- エチレンオリゴメリゼーションにおける構造-性能関係を探求する.
- 対象となる製品形成のための最適なゼオライト孔のサイズを特定します.
主な方法:
- グランド・カノニカル・モンテカルロ (GCMC) のシミュレーションで,ゲストとホストの相互作用をモデル化します.
- 様々なゼオライトフレームワーク (MAZ,AET,DON,FAU,VFI) の研究.
- 触媒活動と選択性を予測するためのマイクロキネティックモデリング.
主要な成果:
- ゼオライトの孔のサイズに依存する,アドソルプションエンタルピーと分子体積の間の線形相関が確立されました.
- 小孔での吸収を制限するステリック排除効果が実証されています.
- アルファオクテンの増産を含む,閉じ込めによる触媒活性と選択性の有意な変化が予測されています.
結論:
- ゼオライトの孔の大きさは,エチレンオリゴメリゼーションにおけるメタルロセンの触媒の振る舞いに重大な影響を及ぼします.
- 閉じ込めの効果は,製品の選択性を制御するために活用することができます.
- シミュレーションは,最適化された閉じられた触媒システムを設計するための経路を提供します.
関連する概念動画
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Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
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