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  • lets talk about zeolites

    hello,
    i would like to start a thread about zeolites in general. post any info you know or can find. i have been doing google searches for the majority of the morning, but i haven't found anything of worth yet...although i did come upon a short paragraph relating to zeolites and TIE's (toxicity identification evaluations)...hopefully, we can use this opportunity to broaden our knowledge of this unique mineral

    zeolites are a group of naturally occuring minerals (i think we all know that) they have large vacant spaces within them to hold cations (m-w def: positively charged ion) like sodium, potassium, calcium, barium, and also molecules like water and ammonia...this is what makes zeolites special...the most common or widely known use of zeolites is in water softeners. calcium that makes water "hard" is exchanged for sodium ions inside the zeolites "charged" with sodium ions...zeolites have also been added to livestock feed to decrease the toxins in the food...

    some info about zeolites:
    http://mineral.galleries.com/mineral...e/zeolites.htm

    the zeolite that has been used in the freshwater industry is most likey the mineral clinoptilolite...i am pretty sure that this is not one of the zeolites we use because it does not work well in saltwater (duh)...one down, a few thousand more to go,LOL :basket:

    some info about clinoptilolite:
    http://www.marineland.com/articles/11Clinoptilolite.asp

    anyway, thats all for now...hopefully we will find more info as time goes on...

  • #2
    Greetings All !

    If you're looking for information pertaining to zeolite material behavior/functioning in saltwater (high ionic solutions) ... please post the link(s) you find. The documentation of zeolite material behavior/functioning in freshwater (low ionic solutions) literally abounds ... have fun sorting through it (it has significantly limited ... but rather suggestive ... relevance to ZEOvit system methodology).

    CosmoKramer and I ... well, me mostly ... got sidetracked onto a brief "tangent excursion" regarding zeolites in the classic ZeoBak thread. Here's an extract from one of the posts ...

    See ... this is how the madness starts ... ...

    If you do a google keyword search using "zeolite", you'll get somewhere around 302,000 hits. In the first 60 listed, you'll find stuff like this ...

    Remember the speculations that the ZEOvit System's zeolites might be manufactured? Check this one out ... good, basic diagrams of reactant selectivity, product selectivity, and transition state selectivity ...

    CalTech's What are Zeolites? (focus is on synthetic zeolites)
    http://www.che.caltech.edu/groups/med/catmat.html

    ...

    And then there's ...

    The database of the Structure Commission of the International Zeolite Association
    http://www.iza-structure.org/databases/

    ...

    It turns out that zeolites can be WILDLY important and useful in a wide range of industrial processes. The madness largely started in the early 1960s when the petroleum industry figured out that zeolites could be used for catalytic reactions ... as Kurt Vonnegut has written, "... and so it goes ... ."
    With the caveat that I'm listing literature that is concerned primarily with the behavior/functioning of zeolites involving freshwater waste management and industrial removal of contaminants, some of my more recent zeolite searches yielded ...

    Influence of Quaternary Ammonium on Sorption of Selected Metal Cations onto Clinoptilolite Zeolite
    Zhaohui Li, Daniel Alessi and Lori Allen
    http://jeq.scijournals.org/cgi/content/full/31/4/1106


    For anyone interested in the structure of the zeolite that is being used for freshwater applications ...

    Clinoptilolite "cage" structure GIF
    http://www.ees.nmt.edu/bowman/resear...lite_cage.html


    A useful extract if you're interested in some of the concepts used with reefkeeping as applied by chemists and hydrologists (among others) ... might be helpful with future google explorations ...
    Surfactants are water-soluble organic molecules which have both hydrophillic and hydrophobic properties. Cationic surfactants have a positively charged headgroup attached to a hydrocarbon moiety. Above the critical micelle concentration, individual surfactant molecules self-associate into micellular clusters. When exposed to a surface, surfactants can sorb as monomers, admicelles, or hemimicelles.

    Extracted from:
    Zeolite-Surfactant Interactions
    Robert S. Bowman, Professor of Hydrology
    http://www.ees.nmt.edu/bowman/resear...eoSurfInt.html
    What's the point of including this? From a generalized perspective, "surfactants" could be considered among the "reactants" that participate in the formation of "mulm" on the surface of ZEOvit media ... and they can do funny "associative" things ... things which may influence the health of our specimens profoundly. Merely a suggestion ... FWIW.


    Remembering that the literature regarding zeolites is dominated by freshwater, industrial, and chemical application information (... and unless specifically focused on ionic medium applications cannot be used in any direct argumentation in support of ZEOvit methodology ...), those who scoff at the very idea that zeolites could have application in ionic solutions might wish to consider ...
    Microporous materials, such as zeolites (see figure 1) with pores less than 1 nm, have tremendous internal surface area and consequently are widely used as molecular sieves, selective sorbents as well as highly active shape-selective catalysts ...

    Extracted from:
    Zeolitisation of Diatoms
    M.W. Anderson, S.M.Holmes, R. Mann, P. Foran, and C.S. Cundy

    Remembering that the literature regarding zeolites is dominated by freshwater, industrial, and chemical application information (... and unless specifically focused on ionic medium applications cannot be used in any direct argumentation in support of ZEOvit methodology ...), those who are willing to admit the possibility that the behavior of zeolites in a freshwater medium is potentially suggestive of the behavior of zeolites in a saltwater medium (albeit in a significantly less efficient manner) might wish to consider ...
    The equilibrium data fitted the Langmuir sorption model, a possible indication of a monolayer coverage of ammonium ions on the surface of the particle. The Langmuir correlation of the equilibrium data suggested that ion exchange might have been the dominant sorption mechanism. The zeolite seemed to have some fairly good potential for ammonia removal ...

    Extract from:
    Ammonia removal from an aqueous solution by the use of a natural zeolite.
    B.N.K. Njoroge and Slade Gilbert Mwamachi
    J. Environ. Eng. Sci./Rev. gen. sci. env. 3(2): 147-154 (2004)
    You can get lost in this stuff ... Lord knows I have ...

    JMO ... HTH
    "When the going gets weird, the weird turn pro."
    Hunter S. Thompson

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