シングル・サイト・プラチナ・カタリストに対するヘキサン・リフォーミングのメカニズムに関する洞察
Shuchen Zhang1, Luning Chen1, Zhiyuan Qi1
1Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|September 14, 2020
まとめ
シングルサイトプラチナ触媒 (Pt1/CeO2) は,サイクル化および芳香化のためのn-ヘクサンのリフォーム選択性を著しく高めます. この進歩は,炭化水素活性化のための効率的な異質な触媒の設計のための新しい経路を提供します.
科学分野:
- 異質な触媒
- 材料科学
- 化学工学
背景:
- ハイオクタンガソリンの製造には n-ヘクサンのリフォームが不可欠です
- 炭化水素反応の選択性を制御することは,触媒の重要な課題です.
- セリア (CeO2) を支持するプラチナベースの触媒は,リフォーム反応のために広く研究されています.
研究 の 目的:
- プラチナ粒子の大きさの n-ヘクサンのリフォーム選択性への影響を調査する.
- サイクル化,芳香化,C−C結合破裂を制御する反応メカニズムを解明する.
- シングルサイトプラチナ触媒の優れた性能を示すために.
主な方法:
- シングルサイト Pt1/CeO2,Ptクラスター/CeO2,Ptナノ粒子/CeO2の合成
- 触媒構造と活性部位の特徴
- ガス相 n-ヘクサンのリフォーム反応は,様々な温度で行われます.
- 選択性と変換を決定する反応産物の分析
主要な成果:
- シングルサイトPt1/CeO2は,350 °Cでのサイクル化および芳香化に対して>86%の選択性を示した.
- Pt1/CeO2は400°Cで58.8h-1の回転頻度を示し,Ptクラスターに匹敵し,ナノ粒子に優れている.
- Ptクラスターとナノ粒子は,単一サイト触媒とは異なり,隣接する活性サイトのためにC-C結合破裂を好みました.
結論:
- シングルサイトPt1/CeO2触媒は,n-ヘクサンのリフォーミングにおけるサイクリングとアロマ化のための選択性を著しく高めます.
- シングルサイト触媒におけるリング中間物質の顕著な吸附は脱水循環と芳香化を誘発する.
- Ptサイズの役割を理解することは,炭化水素活性化のための高度な異質な触媒の設計に不可欠です.
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