Andrea,

I've got an alternative zeolite that I would be glad to send you a few grams
of. UOP molecular sieves Type IE-95, size 20x50. Frank Nagy was the Sales
Engineer (216) 734-1688 for UOP (Des Plaines IL) as a few years ago. We had
a post doc working at our facility (Dr. Harvey Bootsma) who was measuring
dissolved NH4+ in Lake Michigan.  He successfully used this brand of zeolite
but as I recall he conditioned it by baking at 200C for 2 hours.  If the
temperature was too high or the baking time too long, the zeolite structure
was damaged and NH4+ extraction was inefficient. Let me know if you are
interested in trying this, I've also got more details about his method if
your student wants to get in touch with me (it may be quicker than getting
in touch with Harvey as he is living in Malawi now.

Harvey Bootsma
SADC/GEF Lake Malawi?Nyasa Biodiversity Conservation Project
p.o. Box 311
Salima, Malawi
Africa Phone/Fax 011-265-744-183

Best, Margaret






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Margaret B. Lansing
U.S. Dept. of Commerce
National Oceanic & Atmospheric Administration
Great Lakes Environmental Research Laboratory
2205 Commonwealth Blvd.
Ann Arbor, MI  48105
[log in to unmask]
313-741-2289 (lab)
313-741-2210 (office)
313-741-2055 (fax)
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