Alkaline Treatment of Iron-Containing MFI Zeolites. Influence on Mesoporosity Development and Iron Speciation

详细信息    查看全文

• 作者：Johan C. Groen ; Llu&iacute ; s Maldonado ; Elise Berrier ; Angelika Brü ; ckner ; Jacob A. Moulijn ; Javier P&eacute ; rez-Ram&iacute ; rez
• 刊名：Journal of Physical Chemistry B
• 出版年：2006
• 出版时间：October 19, 2006
• 年：2006
• 卷：110
• 期：41
• 页码：20369 - 20378
• 全文大小：577K
• 年卷期：v.110,no.41(October 19, 2006)
• ISSN：1520-5207

文摘

The effects of alkaline treatment on the mesoporosity development and iron speciation in Fe-MFI zeoliteshave been investigated. To this end, a variety of samples derived from different synthetic routes and havingdistinct Si/Al ratios and Fe content were treated in NaOH solutions and characterized by N₂ adsorption,SEM, TEM, UV/vis spectroscopy, and EPR. The alkaline treatment induces a significant intracrystallinemesoporosity development by framework silicon extraction and promotes disintegration of oligomeric ironspecies. Iron in framework positions has shown to provoke mesopore formation, whereas nonframework ironspecies suppresses silicon leaching and lowers the extent of extra porosity.