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控制金属氧化物可降解性,以有效激活碳化合物中的C-H键

Guo-Qing Yang^1,2, Yiming Niu³, Vita A Kondratenko²

¹Key Laboratory of Syngas Conversion of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.

Angewandte Chemie (International ed. in English)

|September 13, 2023

概括

研究人员开发了一种简单的水性氨处理方法,以准确准备金属氧化物催化剂. 这种pH控制的方法调整了活性位点,提高了脱等反应中的催化剂性能.

科学领域:

催化剂是一种催化剂.
材料科学材料科学材料科学
化学工程是化学工程的重要组成部分.

背景情况:

对催化剂结构和活性位点的精确控制对于设计高性能催化剂至关重要.
现有的催化剂制备方法可能很复杂,缺乏微调能力.

研究的目的:

引入一种简单的,可调节pH值的方法,用于准确制备支和散装金属氧化物催化剂.
为了证明该方法在控制催化剂特性,如活性点度和可减少性方面的适用性.
在关键的工业反应中验证使用这种方法制备的催化剂的性能.

主要方法:

在水性氨溶液中利用金属氧化物的溶解和同时沉.
通过调整溶液的pH,精确控制协调不和Al位点的度.
将该方法应用于VOx-Al2O3和CeO2-ZrO2-Al2O3催化剂系统.
评估乙基氧化脱和非氧化甲脱过程中的催化剂性能.

主要成果:

水性氨处理方法允许精确控制催化剂制备.
调整溶液的pH值有效地改变了协调不和Al位点的度,影响了V-O-Al键强度和VOx可还原性.
该方法成功控制了大量CeO2-ZrO2-Al2O3催化剂的可还原性.
制备的催化剂在乙基转化为 styrene 和转化为 propene 的过程中显示出显著的应用潜力.

结论:

已经开发出一种使用水性氨处理制备金属氧化物催化剂的简单而精确的方法.
这种可调节pH的方法为控制催化剂结构和性能提供了一种多功能策略.
该方法可扩展到各种可溶于氨溶液的金属氧化物催化剂,在催化中具有广泛的适用性.

关键词:

C−H 激活方式脱水化的过程可降解性可降解性量身定制催化剂结构瓦纳氧化物瓦纳氧化物

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