アクティブサイトを超えて:エチレンダイメリゼーションのための金属有機フレームワークサポートのNi触媒の活性と選択性を調整する
Jian Liu1, Jingyun Ye2, Zhanyong Li1
1Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|August 25, 2018
まとめ
特定のリガンドを金属有機フレームワーク (MOF) に導入することで,エチレンオリゴメリゼーションにおけるニッケル触媒の選択性を正確に制御し,望ましいC4製品に優遇する. この改変は,調整されたサポート特性を介して異質な触媒を強化します.
科学分野:
- 異質な触媒
- 材料科学
- 有機金属化学
背景:
- メタル・オーガニック・フレームワーク (MOF) は,異質な触媒のための多用途の支柱です.
- MOFの特性を調整することは,触媒の活性と選択性を制御するために不可欠です.
- エチレンオリゴメリゼーションは,製品の選択性に関する課題を持つ重要な産業プロセスです.
研究 の 目的:
- NU-1000 MOFサポートのステリックと電子特性を変更する.
- エチレンオリゴメリゼーションのためのNi (II) 触媒部位に導入されたリガンドの効果を調査する.
- エチレンオリゴメリゼーションでC4種を選択的に生成する.
主な方法:
- 原子層沉積 (ALD) のようなプロセスで,ヘクサフッロアセチラセトナート (Facac-) とアセチラセトナート (Acac-) リガンドをNU-1000に導入する.
- 変更されたMOFのサポートにNi ((II) サイトをインストールします.
- 改変した触媒を用いたエチレン寡合化反応.
- 反応メカニズムを解明するための密度関数理論 (DFT) の計算.
主要な成果:
- 無修正のNU-1000サポートされたNi ((II) サイトは,C4,C6,C8,およびポリマー製品の混合物を生産しました.
- Ni-Facac-AIM-NU-1000とNi-Acac-AIM-NU-1000の両方の触媒はC4製品に対して定量的選択性を示した.
- DFTの計算では,リガンドをリガートニッケルに再配置することで,C−C結合活性化バリアが増加したことが示された.
結論:
- 構造調節サポート変形剤は,MOFに位置する異質な触媒の活性と選択性を制御する上で重要な役割を果たします.
- 分子変形剤の蒸気相配送は,触媒のサポートの簡単な,結晶学的に定義された修正を可能にします.
- MOFサポートのリガンド改変は,触媒的結果の正確な制御のための強力な戦略を提供します.
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