化学選択性アルキン/オレフィン分離のためのゼオライト孔内部の制御
Yuchao Chai1, Xue Han2, Weiyao Li2
1School of Materials Science and Engineering and National Institute for Advanced Materials, Nankai University, Tianjin 300350, China.
Science (New York, N.Y.)
|May 30, 2020
まとめ
この研究は,ポリマー生産に不可欠な低いオレフィンからアルキン不純物を非常に選択的に除去するために,ニッケルサポートされたファウジャサイト (Ni@FAU) ゼオライトを使用する新しい方法を導入しています.
科学分野:
- 材料科学
- カタリシス
- 分離科学
背景:
- 高純度ポリマーグレードの低オレフィンを作るには,アルキン不純素の効率的な除去が不可欠です.
- 既存の分離方法は,高い選択性と効率性を達成する上で課題に直面しています.
研究 の 目的:
- ゼオライトの孔内を制御するための新しい戦略を開発し,アルキンの吸収と分離を向上させる.
- アルキンをオレフィンから分離するために,ファウザサイト (FAU) ゼオライト内の閉じ込められたニッケル (II) 部位の性能を調査する.
主な方法:
- 孤立した開いたニッケル (II) サイトをFAUゼオライトの6つ構成のリング内に閉じ込めます.
- アセチレン/エチレン,プロピーネ/プロピーネ,ブチネ/1,3-ブタジエンの混合物の吸収と分離を Ni@FAU で試験する.
- 結合メカニズムを解明するために,in situ 中性子 difraktion と inelastic 中性子 scattering を利用する.
主要な成果:
- Ni@FAUは,環境条件下で顕著なアルキンの吸収を示した.
- アセチレン/エチレンで100度,プロピネ/プロピレンで92度,ブチネ/1,3-ブタディーネで83度という前例のないダイナミック分離選択性を達成した.
- メタステーブルな[Ni (II) (C2H2) ]複合体によるアセチレンの化学選択的および可逆的結合を特定した.
結論:
- 限られた金属部位を介してゼオライトの孔内化学を制御することは,工業的な分離のための強力なアプローチを提供します.
- スケーラブルなゼオライトベースの吸着剤は,石油化学産業における挑戦的な浄化プロセスに重要な可能性を秘めています.
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