軽度な条件下で,改変されていないコバルトカルボニルによって触媒化された水酸化
Baoxin Zhang1, Christoph Kubis1, Robert Franke2,3
1Leibniz Institute for Catalysis e.V., Albert-Einstein-Str. 29a, 18059 Rostock, Germany.
Science (New York, N.Y.)
|September 8, 2022
まとめ
改変されていないコバルトカルボニルは,温和な条件下 (140°C,30barシンガス) で安定した水酸化触媒である. この発見により 表面活性剤と可塑剤の生産に より効率的な 産業路線が生まれました
科学分野:
- カタリシス
- 有機金属化学
- 産業化学
背景:
- コバルトカルボニル触媒は,工業用水酸化に不可欠であり,通常は高圧 (100~400バー) と高温 (100~250°C) を要求する.
- 既存の方法は厳しい条件で エネルギー効率とプロセスのコストに影響を及ぼします
研究 の 目的:
- 変化しないコバルトカルボニル触媒の安定性と活性性を,著しく減少した合成ガス圧力と適度な温度下で調査する.
- 改良されていないコバルトカルボニルの性能を,改良されたリガンドシステムと比較して評価する.
主な方法:
- 反応速度と触媒の振る舞いを評価するために,運動学的研究が採用された.
- 局所赤外線 (IR) スペクトロスコーピーは,主要な触媒中間物質,特にコバルトテトラカルボニル水素 (HCo ((CO)) の安定性を確認するために使用されました.
- 低シンガス圧力 (30バー) と140°Cで,分岐内オレフィンを用いて水酸化反応を行った.
主要な成果:
- 改変されていないコバルトカルボニルは140°Cと30barのシンガスで安定した触媒活性を示し,再現できないビスフォスフィン・コバルト (II) 触媒と比較できる.
- 枝分かれした内部オレフィンをアルデヒドに変換することで,高い地域選択性が得られた.
- コバルトテトラカルボニル水素 [HCo ((CO)) 4 ] の中間物質の安定性はスペクトル検査で確認された.
- 低濃度のリンとコバルト (0. 6以下) は,ビスホスフィンによる軽微な促進効果を示した.
結論:
- 改変されていないコバルトカルボニルは,工業的に重要な温和条件 (140°C,30barシンガス) の下では,堅固で活性な水酸化触媒である.
- この発見は,高圧プロセスの実行可能な代替案であり,エネルギー消費と運用コストを削減する可能性があります.
- この研究は,改変されていないコバルト触媒の有効性を強調し,特定の水酸化アプリケーションの複雑なリガンドシステムの必要性を疑問視しています.
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