Quantification of ammonia binding sites in Davison (Type 3A) zeolite desiccant : a solid-state Nitrogen-15 MAS NMR spectroscopy investigation.

Alam, Todd Michael ; Holland, Gregory P. ; Cherry, Brian Ray

Sandia National Laboratories

关键词: Chemical Shift;    Zeolites;    Desiccants;    37 Inorganic, Organic, Physical And Analytical Chemistry;    Adsorption;   

DOI  :  10.2172/918356
RP-ID  :  SAND2004-0022
RP-ID  :  AC04-94AL85000
RP-ID  :  918356

美国|英语

来源: UNT Digital Library

【 摘 要 】

The quantitative analysis of ammonia binding sites in the Davison (Type 3A) zeolite desiccant using solid-state {sup 15}N MAS NMR spectroscopy is reported. By utilizing 15N enriched ammonia ({sup 15}NH{sub 3}) gas, the different adsorption/binding sites within the zeolite were investigated as a function of NH{sub 3} loading. Using {sup 15}N MAS NMR multiple sites were resolved that have distinct cross-polarization dynamics and chemical shift behavior. These differences in the {sup 15}N NMR were used to characterize the adsorption environments in both the pure 3A zeolite and the silicone-molded forms of the desiccant.