効率的なプロパンの脱水化のためのZnOx種のインサイト形成
Dan Zhao1,2, Xinxin Tian2,3, Dmitry E Doronkin4
1State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing, P. R. China.
Nature
|November 11, 2021
まとめ
環境に優しい亜鉛酸化物 (ZnO) 触媒は,プロパン脱水 (PDH) にプロペンの持続可能な代替品を提供します. これらの新しい触媒は,従来の方法と比較してプロペンの生産性が著しく高いことを示しています.
科学分野:
- カタリシス
- 材料科学
- 化学工学
背景:
- プロパン脱水 (PDH) は重要な産業用化学物質であるプロペンの生産に不可欠ですが,現在の方法は環境上の課題に直面しています.
- 既存の技術は有毒なクロム (Cr) を使用し,再生には有害な塩素を必要とし,よりグリーンな代替品が必要である.
- 石油ベースのクラッキングプロセスはプロペンの伝統的な源であり,代替生産ルートの必要性を強調しています.
研究 の 目的:
- プロパン脱水化 (PDH) のための環境に適合する触媒を開発する.
- 支持された亜鉛酸化物 (ZnO) 種のインシット形成と活動を調査する.
- 新しい触媒の性能を商業標準と比較する.
主な方法:
- 商用ZnOとサポート (ゼオライトまたは金属酸化物) を使用してサポートされた触媒の準備.
- 高い温度 (>550°C) でサポートヒドロキシル (OH) グループとの反応による活性ZnO種のインシット形成.
- 活性種とその形成メカニズムを特定するために,補完的な方法を用いて特徴づけます.
- ZnO-シリカリート-1触媒と商用アナログを用いて,工業的に重要な条件下でベンチマーク試験を行う.
主要な成果:
- 活性ZnO種は,ZnOと欠陥のあるサポートOHグループとの反応によって,in-situで形成されます.
- 開発されたZnO-シリカライト-1触媒は,プロペンの生産性が約3倍に達した.
- プロペンの選択性は,商用催化剤と比較して同じであった.
- 触媒の安定性は約400時間の動作で実証された.
結論:
- 環境に適合する ZnO 触媒はPDH 用に効果的に準備できます.
- 欠陥OH群を伴う in-situ形成メカニズムは,触媒の活動に鍵となる.
- 開発されたZnOベースの触媒は,現在のPDH技術に対して有望で高性能な代替品です.
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