物理化学学报 >> 2005, Vol. 21 >> Issue (07): 746-751.doi: 10.3866/PKU.WHXB20050710

研究论文 上一篇    下一篇

构筑可控催化氧化性能催化剂用于醇的转化

纪红兵; 王乐夫; 陈清林   

  1. 华南理工大学化工与能源学院, 广州 510640
  • 收稿日期:2004-11-29 修回日期:2005-01-30 发布日期:2005-07-15
  • 通讯作者: 纪红兵 E-mail:cehbji@scut.edu.cn

Development of Catalysts with Tunable Catalytic Oxidative Performance for Alcohols Conversion

JI Hong-bing; WANG Le-fu; CHEN Qing-lin   

  1. School of Chemical and Energy Engineering, South China University of Technology, Guangzhou 510640
  • Received:2004-11-29 Revised:2005-01-30 Published:2005-07-15
  • Contact: JI Hong-bing E-mail:cehbji@scut.edu.cn

摘要: 通过金属离子替代的方法设计了催化氧化性能不同的Mg-Al-Ru-CO3类水滑石、Co-Al-Ru-CO3类水滑石和Ru-Co(OH)2-CeO2等三种催化剂. XRD实验表明钌部分替换制得的Mg-Al-Ru-CO3和Co-Al-Ru-CO3可保持水滑石的结构; 但用铈替代铝之后得到的Ru-Co(OH)2-CeO2催化剂无法保持水滑石的结构, 而是由氢氧化钴和二氧化铈的微晶组成. XPS 和Ru K-edge XAFS的测试结果证实Mg-Al-Ru-CO3催化剂中钌被等键长的6个氧原子包围, 该催化剂可有效地催化氧化醇类; Co-Al-Ru-CO3催化剂中钌被两种键长不等的6个氧原子包围, 其中短键长的Ru═O是催化氧化性能增强的原因; Ru-Co(OH)2-CeO2催化剂中钌被两种键长不等的5个氧原子包围, 其对于各类醇均有高效的催化氧化性能, 原因归功于配位数少的钌物种.

关键词: 钌, 水滑石, 醇, EXAFS, 催化氧化

Abstract: The catalytic oxidative performance of Mg-Al-Ru-CO3 hydrotalcite, Co-Al-Ru-CO3 hydrotalcite, Ru-Co(OH)2-CeO2 was well designed and tuned with substitution method. The XRD characterization presented that both the Mg-Al-Ru-CO3 catalyst and Co-Al-Ru-CO3 catalyst could keep hydrotalcite structure after the partial substitution of Al with Ru. However, after the substitution of Al with Ce, the structure of the obtained Ru-Co(OH)2-CeO2 catalyst was microcrystals of cobalt hydroxide and cerium oxide. The results of XPS and Ru K-edge XAFS suggested that the isolated Ru atom in Mg-Al-Ru-CO3 hydrotalcite was surrounded by 6 oxygen atoms with only one type of Ru-O shells, which catalyzed alcohols oxidation efficiently; the isolated Ru atom in Co-Al-Ru-CO3 hydrotalcite was surrounded by 6 oxygen atoms with two types of Ru-O shells, therein unsaturated Ru═O double bond was responsible for higher catalytic efficient for alcohols oxidation; the isolated Ru atom in Ru-Co(OH)2-CeO2 catalyst surrounded by 5 oxygen atoms with two types of Ru-O shells, therein the unsaturated coordination of Ru was the key to attain higher ability for various kinds of alcohols oxidation.

Key words: Ruthenium, Hydrotalcite, Alcohols, EXAFS, Catalytic oxidation