Subject: Zeolite
After having received some fire damaged textiles for treatment, I have searched the Internet for the possibilities of removing odor and found the posting by Jane C. Hammond in Cons DistList Instance 14:61, May 10th 2001, who recommends using Zeolite Paper (Conservation Resources) for wrapping objects to remove the odor. Trying to find information about Zeolite in general, I found a technical bulletin "Zeolite--a versatile air pollutant adsorber" by the United States Environmental Protection Agency, dated July 1998 <URL:http://www.epa.gov/ttn/catc/dir1/fzeolite.pdf>, in which I found the following sentence: "Zeolite can be a solid acid catalyst. It can function as a strong acid (though it remains solid) when the hydration has substituted a hydrogen for the additional valence electron, or isoelectronic exchange with the aluminum occurs." Now, what does this mean? As I understand, there are many different synthetically produced Zeolites. For paper, a hydrophobic zeolite is normally used (although--as Conservation Resources has no information available on the net, I do not know the specifics of their paper as yet). Hydrophobic Zeolites seem to be produced by enhancing the amount of Si in relation to Al. Can I therefore conclude, that, if the paper really is coated with hydrophobic Zeolite, hydration will not be a problem and, because of the reduced (or even eliminated?) amount of Al isoelectronic exchange should not be a problem either? Can someone who has more chemical knowledge than I do please comment on this? Have there been more recent tests with Zeolite coated cardboards or papers ("MicroChamber", "ArtCare")? I am aware of the article "Zeolite Molecular Traps and Their use in Preventative Conservation by Siegfried Rempel in WAAC Newsletter vol 18, No 1 January 1996 <URL:http://palimpsest.stanford.edu/waac/wn/wn18/wn18-1/wn18-106.html>. In case of a whole collection and archives being affected by smoke during fire, has somebody used Zeolite in its granular form instead of wrapping each object? Is this effective at all? Do I need air circulating in order for granular Zeolite to work, or can I simply inclose a bag with a bunch of objects and wrap them airtight (i.e. no circulation). How do I realize if the capacity of adsorption is reached? As far as I understood from what I read about Zeolite, it can be "reactivated" by heating, (thus releasing the trapped gases?). But, will I then change its own structure and create a potentially more harmful substance (see my concern above about the solid acid catalyst)? As becomes evident, I do not yet feel, I understand enough about zeolite to immediately use it. Any help / information is most welcome. Karin von Lerber Prevart GmbH Konzepte fur die Kulturgutererhaltung Oberseenerstrasse 93 CH-8405 Winterthur +41 52 233 12 54 Fax: +41 52 233 12 57 *** Conservation DistList Instance 15:49 Distributed: Saturday, January 12, 2002 Message Id: cdl-15-49-012 ***Received on Friday, 11 January, 2002