在现场形成ZnOx物种以实现高效的脱
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
概括
环保的氧化 (ZnO) 催化剂为脱 (PDH) 提供了一个可持续的替代品. 与传统方法相比,这些新型催化剂的效率显著提高.
科学领域:
- 催化剂
- 材料科学
- 化学工程
背景情况:
- 脱 (PDH) 对于生产关键工业化学物质至关重要,但目前的方法面临环境挑战.
- 现有技术使用有毒的 (Cr) 或需要有害的进行再生,因此需要更绿色的替代品.
- 基于石油的破解工艺是传统的源,突出了替代生产途径的需要.
研究的目的:
- 为脱 (PDH) 开发一种环境相容的催化剂.
- 研究支持的氧化 (ZnO) 物种的现场形成和活性.
- 将新催化剂的性能与商业标准进行比较.
主要方法:
- 使用商业ZnO和支物 (焦化物或金属氧化物) 制备支持催化剂.
- 通过在高温 (> 550°C) 上与支基 (OH) 的反应在现场形成活性ZnO物种.
- 使用补充方法进行表征,以确定活性物种及其形成机制.
- 在工业相关条件下使用ZnO-化-1催化剂和商业类型的基准测试.
主要成果:
- 活性ZnO物种通过ZnO与缺陷的支持OH组的反应在现场形成.
- 开发的ZnO-酸-1催化剂的效率大约是的三倍.
- 与商业催化剂相比,保持了类似的选择性.
- 在约400小时的运行过程中证明了催化剂的稳定性.
结论:
- 可以有效地为PDH准备环境兼容的支持ZnO催化剂.
- 涉及缺陷OH组的现场形成机制是催化剂活性的关键.
- 开发的基于ZnO的催化剂是目前PDH技术的有希望的高性能替代品.
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