Influence of the Si/Al Framework Ratio on the Microporosity of Dealuminated Mordenite as Determined from N₂ Adsorption

Abstract

Dealuminated mordenites depicting SiO₂/Al₂O₃ molar ratios in the range 10‐206 were analyzed through adsorption methods. The Type I‐IV hybrid shape of the N₂ adsorption isotherms at 76 K on dealuminated mordenites indicated rather high micropore contents, though some amount of mesopores of slit‐like geometry was also present. Micropore volumes and sizes were measured through α_S, t, and DA‐plots, as well as by the NLDFT approach. Results indicated that mordenite dealumination caused micropore opening and widening as well as the emergence of further slit‐like mesopores; even though a slight structural collapse toward creation of mesopore zones occurred at high dealumination extents.

Keywords:

• Dealuminated mordenite
• high‐resolution α_s
• plots
• supermicropores
• ultramicropores
• Dubinin‐Astakhov

Acknowledgements

Thanks are given to:

1. The Benemérita Universidad Autónoma de Puebla, México, (VIEP‐BUAP) for financial support through grant II 118102; and

2. Consejo Nacional de Ciencia y Tecnología (CONACYT), Mexico through project 47631‐F.