ゼオライトH-モルデナイトにおけるブロンステッド酸部位の固体MAS NMR研究
Hua Huo1, Luming Peng, Zhehong Gan
1Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-3400, USA.
Journal of the American Chemical Society
|May 5, 2012
まとめ
研究者らは,高度なNMR技術を使用して,H-モルデナイトゼオライト内のブロンステッド酸部位をマッピングしました. この研究は,ゼオライト触媒の理解に不可欠な,異なる酸性サイトの位置とアクセシビリティを明らかにしています.
科学分野:
- 固体NMRスペクトロスコーピー 固体NMRスペクトロスコーピー
- 材料化学 材料化学について
- カタリシス カタリシス カタリシス
背景:
- ゼオライト,特にH-Mordenite (H-MOR) は,重要な産業用触媒である.
- ブロンステッド酸遺跡の正確な位置と性質を理解することは,それらのパフォーマンスを最適化するための鍵です.
- 以前の方法では,H-MOR.内の多様な酸性部位を完全に特徴付ける解像度が欠けていました.
研究 の 目的:
- H-モルデナイトにおけるブロンステッド酸の局所構造と分布を解明する.
- ブロンステッド酸の部位を,そのO−H距離に基づいて区別する.
- これらの酸性部位のアクセシビリティを定量化して,分子探査を行う.
主な方法:
- (17) O-(1) H二重共振NMRスペクトロスコーピーを利用しました.
- クロス・ポラライゼーション・マジック・アングル・スピニング (CPMAS) NMR,CP・ローテーション・エコー・ダブル・レゾンス (CP-REDOR) NMR,ヘテロ核相関 (HETCOR) NMRを使用しています.
- トリメチルフォスフィン吸附を用いた定量化されたサイトアクセシビリティ.
主要な成果:
- 異なるNMR技術と接触時間を用いて,異なるO-H距離を持つ特徴的なブロンステッド酸部位.
- H-モルデナイトの枠組みの中で,異なるタイプのブロンステッド酸の場所の特定の場所の提案.
- 様々なブロンステッド酸の場所のアクセシビリティを決定しました.
結論:
- この研究では,H-モルデナイトの多様なブロンステッド酸部位の地図作成に成功しました.
- NMRスペクトル,特に (17) O-(1) H二重共振は,部位の特徴化に有効です.
- (17) 化学変化の相関は,ゼオライトの研究のための場所の割り当てに役立ちます.
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