在燃烧制成的WOx/ZrO2上促进布伦斯特德酸的形成,用于葡萄糖转化
Wenwen Zhang1, Zichun Wang1, Aleksei Marianov1
1School of Engineering, Macquarie University, 2109, Sydney, NSW, Australia.
ChemSusChem
|July 24, 2024
概括
火焰喷雾热解 (FSP) 产生优质的酸氧化物催化剂,具有增强的布伦斯特酸位 (BAS) 和更高的BAS与易斯酸位 (B/L) 比率. 这些先进的催化剂显著改善了将葡萄糖转化为5-氧甲基 (HMF).
科学领域:
- 不同质的催化剂.
- 材料科学是一种材料科学.
- 表面化学 表面化学
背景情况:
- 酸-氧化物 (WOx/ZrO2) 催化剂对于生物质转化至关重要.
- 传统的浸泡方法通常会产生低于最佳的酸位分布.
- 优化布伦斯特德和易斯酸位点 (B/L) 的比率是催化效率的关键.
研究的目的:
- 合成高度布伦斯特酸位 (BAS) 和高B/L比的WOx/ZrO2催化剂.
- 为了研究催化剂合成方法对酸位属性和分散的影响.
- 评估这些催化剂在将葡萄糖脱水为5-基甲基 (HMF) 的性能.
主要方法:
- 用于催化剂合成的单阶段火焰喷雾热解 (FSP).
- 与通过常规浸 (IM) 制备的催化剂进行比较.
- 酸位点 (BAS和易斯酸位点 - LAS) 和它们的比率的表征.
- 催化测试葡萄糖脱水到HMF.
主要成果:
- 与IM (~50%BAS,B/L~1) 相比,FSP合成产生了具有显著更高BAS (~80%) 和B/L比率 (~4) 的WOx/ZrO2.
- 在FSP催化剂中,WOx物种表现出极好的表面分散,形成3DZr-WOx集群.
- 确定B/L比为葡萄糖转换的关键因素,而不是总酸度.
- 最佳的FSP-WOx/ZrO2催化剂实现了近100%的葡萄糖转化和56-69%的HMF选择性.
结论:
- 火焰喷雾热解是一种有效的方法,用于生产具有定制酸性质的高活性WOx/ZrO2催化剂.
- 高的B/L比对于高效的葡萄糖脱水至HMF至关重要.
- FSP-WOx/ZrO2催化剂的性能与HMF生产的同质催化剂相当.
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