Sorption of nitrogen, oxygen and argon in mordenite type zeolites

Abstract

Sorption of nitrogen, oxygen and argon is studied in mordenite type zeolites having different Si/Al ratios using elution gas chromatography. Sorption isotherms of water, benzene and nitrogen show that ZM-060 is a small pore zeolite. The higher values of

<span style="font-size:12.0pt;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";mso-ansi-language:en-in;mso-fareast-language:="" en-in;mso-bidi-language:ar-sa"="" lang="EN-IN">nitrogen Henry constant, nitrogen selectivity and heats of sorption observed for ZM-060 have been attributed to the presence of Na⁺ ions in this sample. Comparison of heats of sorption of nitrogen and argon in ZM-060 with those in NaA and NaX reveal that the sorbate molecules experience higher interactions with extra-framework Na⁺<span style="font-size:12.0pt;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";mso-ansi-language:en-in;mso-fareast-language:="" en-in;mso-bidi-language:ar-sa"="" lang="EN-IN"> ion as well as lattice oxygen atoms in mordenite structure. Higher heats of sorption of nitrogen in mordenite ZM-060 have been attributed to the restricted rotational freedom of sorbed nitrogen molecules in the channels of mordenite.</span></span>