ボロン窒素ナノチューブのO-O種はプロパン酸化脱水のためにオレフィンを増やす
Panpan Li1, Xuejing Zhang2, Jingnan Wang3
1Department of Physics, School of Science, Beijing Jiaotong University, Beijing 100044, P. R. China.
Journal of the American Chemical Society
|March 22, 2022
まとめ
ボロン-酸素-窒素ナノチューブ (BONNT) は,O-O種で酸化プロパン脱水化 (OPDH) の性能を大幅に向上させる. これらの新種の触媒は,従来の酸ナノチューブ (BNNT) に比べて優れた活性,選択性,および安定性を示しています.
科学分野:
- 材料科学
- カタリシス
- 化学工学
背景:
- ボロン・ニトリド (BN) は,酸化プロパン脱水化 (OPDH) のカタリストとして知られています.
- 酸素を含有するボロン種,例えばBO·およびB(OH) O3-は,通常,OPDHのBN触媒の活性部位とみなされる.
研究 の 目的:
- O-O種で濃縮された新しいボロン-酸素-窒素ナノチューブ (BONNT) 触媒を開発する.
- OPDHに対するBONNTの強化された触媒活性,選択性,および安定性を調査する.
主な方法:
- 漸進的置換戦略を用いたBONNTの合成
- BONNTのOPDHに対する触媒試験を525 °Cで行う.
- 475°Cで150時間の長期安定性試験
- プロパンと酸素の代替処理を含む実験分析
- 反応メカニズムの解明のための理論的計算.
主要な成果:
- BONNTは525°Cでプロパン変換率64.4%とオレフィン生産率48.6%を達成し,BNNTを2.8倍上回った.
- BONNTは,475°Cでの150時間の反応後でも,持続的な高オレフィン産出を示した.
- B ((OH) O3-とO-O種は,BNNTのB ((OH) O3-センターとは異なり,BONNTの活性センターとして識別された.
結論:
- BONNTの共存するB ((OH) O3-とO-O種は,OPDHの活性センターとして作用する.
- O-O種は,エネルギーバリアが低い脱水経路を通じてプロピレン (C3=) とエチレン (C2=) を生産する上でより効果的です.
- BONNTはOPDHの非常に活発で選択的で安定した触媒であり,BNNTよりも著しい改善をもたらします.
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