PHYSISORPTION OF ARGON, NITROGEN AND OXYGEN BY MCM-41, A MODEL MESOPOROUS ADSORBENT

Adsorption isotherms of argon, nitrogen and oxygen have been determine d at 77 K on a sample of MCM-41, a novel form of aluminosilicate. All the isotherms are Type IV in the IUPAC classification. The argon and o xygen isotherms exhibit well defined hysteresis loops, whereas the nit rogen isotherm is completely reversible. This unusual character is att ributed to capillary condensation taking place within a narrow range o f tubular pores of effective width 3.3-4.3 nm. MCM-41 shows considerab le promise as a model mesoporous adsorbent.