摘要
本文运用ＴＰＤ－ＭＳ、ＴＰＲ等方法研究了Ａｇ／γ－Ａｌ_２Ｏ_３催化剂的氧脱附和还原性能。结果表明，Ａｇ／γ－Ａｌ_２Ｏ_３催化剂表面银物相由Ａｇ０和Ａｇ＋（Ａｇ２Ｏ）组成，其中Ａｇ＋所占比例随负载量增加而减少。Ａｇ／γ－Ａｌ_２Ｏ_３催化剂有三个脱氧峰，并且随着Ａｇ负载量的增加，脱氧峰从高温向低温依次出现。低温脱氧峰（３７０℃）归属为结晶态Ａｇ２Ｏ的分解，高温脱氧峰（６５０和８００℃）为分散在γ－Ａｌ_２Ｏ_３表面并且与Ａｌ_２Ｏ_３发生相互作用的Ａｇ_２Ｏ的分解。ＴＰＲ有三个还原峰；高温峰（２３０℃）为结晶态Ａｇ_２Ｏ的还原，低温峰（１００和１２０℃）为分散在γ－Ａｌ_２Ｏ_３表面的Ａｇ_２Ｏ的还原。
In this paper, the desorption properties of surface oxygen and the reducibilities of catalysts were investigated by means of TPD-MS,TPR,etc.The surface compositions of Ag/γ-Al2O3 are Ag0 and Ag+(Ag2O),Ag0 content is directly proportional to the amount of supported Ag.TPD spectra of catalysts show three peaks at 370,650 and 800℃, respectively,which are associated with the decomposition of the particulate Ag2O phase,the dispersed Ag2O phase(Ⅰ) and the dispersed Ag2O phase(Ⅱ). The Ag oxide-support interaction of the dispersed Ag2O phase(Ⅱ) is stronger than that of the dispered Ag2O phase(Ⅰ) TPR spectra of Ag/γ-Al2O3 catalysts show three peaks at 100,120 and 370℃ which are associated with the dispersed Ag2O phase(Ⅱ).the dispersed Ag2O phase(Ⅱ) and particulate Ag2O phase.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1996年第3期198-201,共4页
Journal of Fuel Chemistry and Technology
基金
浙江省教委资助
关键词
催化剂
TPR
TPD
银
三氧化二铝
Ag/γ-Al_2O_3 catalysts,oxygen desorption ,reducibities
