選択的なメタノール・カルボニル化から,異質な原子分散型ReO4/SiO2触媒による酸性化
Ji Qi1, Jordan Finzel1, Hossein Robatjazi1
1Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93117, United States.
Journal of the American Chemical Society
|July 22, 2020
まとめ
この研究は,メタノールをエセティック酸に炭素化するために,原子的に分散したシリカ上のレニウムを用いた新しい異質な触媒を導入し,高選択性および腐食性ハライドなしで活性化します.
科学分野:
- カタリシス
- 材料科学
- 化学工学
背景:
- メタノルを酸性酸に炭素化するには,通常,腐食性ハライドプロモーターを持つ均質な触媒を使用します.
- このプロセスのための効率的な異質な触媒の開発は,産業用アプリケーションにとって極めて重要です.
研究 の 目的:
- メタノールをエステル酸に炭素化するためのハライドフリーで異質な触媒を開発する.
- 原子的に分散した酸化レニウムの性能とメカニズムを研究する.
主な方法:
- トリエタノアミンを使用してSiO2上に原子分散のReO4を合成する.
- AC-STEM,UV-VISスペクトロスコーピー,XASを用いた特徴づけ
- 反応性測定,運動分析,現地FTIR,そして現地XAS.
主要な成果:
- SiO2に原子的に分散したReO4は, >93%のエセティック酸への選択性を示し, >60%の変換を示した.
- 触媒はガス相メタノール炭化で60時間安定した性能を示した.
- Rh プロモーターの追加により,選択性がさらに高められ,>96%となった.
結論:
- 惰性SiO2に原子的に分散したReO4は,酸生成のための有望なハライドフリー異質な触媒です.
- 提案されたメカニズムはメタノール活性化とCO挿入を含む.
- この研究は,アルコールの炭化化における新しい異質な触媒の道を開く.
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