Use of natural Zeolite to Produce Geopolymers

[Deleted]

Geopolymer synthesis using alkaline activation of natural zeolite
www.c-s-h.ir/wp-content/uploads/2014/04/Geopolymer-synthesis-using-alkaline-activation-of-natural-zeolite.pdf

Here in Germany micronized natural zeolite is currently sold at Ebay starting at about 15€ for 25Kg, shipping included.
The content of clinoptilolite varies from over 80% to above 90%.
From the chemicaly composition it seems to be a mixture of calzium clinoptilolite and potassium clinoptilolite.
The CaO content varies from about 3.5% to about 8%.
The inner surface is about 30-60 square meters per gramm, which makes it highly reactive if it is micronized.
 
I have got some with 50 microns and a CaO content of 3.5-5%.
Due to the CaO content it hardens with waterglass alone at room temperature within one or  two days,
slower if mixed with clay.
Additional lime will harden it faster
With rather high amounts of lye even without waterglass and no additional lime it may harden within a few minutes.

The USA has large deposites of clinoptilolite.

Mindat has a map and a list (340 items) with localities for clinoptilolite around the world.
www.mindat.org/min-1082.html

the more common mineral zeolites are analcime, chabazite, clinoptilolite, heulandite, natrolite, phillipsite, and stilbite.
en.wikipedia.org/wiki/Zeolite#Natural_occurrence

Zeolite Group at Mindat
www.mindat.org/min-4395.html

The list of localities for the zeolite group has 10000 items.

[Deleted]

Update.
Both natural zeolite mixtures with water glass,
pure and mixed with kaolin became very hard.


BTW
At Ebay Italy and France 25kg 50 microns are sold currently for EUR 28,31
including shipping to European Union countries from Germany.
25kg 200 microns for EUR 21,50, likely 200 microns are sufficient, but I do not know for sure.

[firewatcher]

Jun 11, 2016 6:02:59 GMT -8 @karl said:

Geopolymer synthesis using alkaline activation of natural zeolite
www.c-s-h.ir/wp-content/uploads/2014/04/Geopolymer-synthesis-using-alkaline-activation-of-natural-zeolite.pdf

Here in Germany micronized natural zeolite is currently sold at Ebay starting at about 15€ for 25Kg, shipping included.
The content of clinoptilolite varies from over 80% to above 90%.
From the chemicaly composition it seems to be a mixture of calzium clinoptilolite and potassium clinoptilolite.
The CaO content varies from about 3.5% to about 8%.
The inner surface is about 30-60 square meters per gramm, which makes it highly reactive if it is micronized.
 
I have got some with 50 microns and a CaO content of 3.5-5%.
Due to the CaO content it hardens with waterglass alone at room temperature within one or  two days,
slower if mixed with clay.
Additional lime will harden it faster
With rather high amounts of lye even without waterglass and no additional lime it may harden within a few minutes.

The USA has large deposites of clinoptilolite.

Mindat has a map and a list (340 items) with localities for clinoptilolite around the world.
www.mindat.org/min-1082.html

the more common mineral zeolites are analcime, chabazite, clinoptilolite, heulandite, natrolite, phillipsite, and stilbite.
en.wikipedia.org/wiki/Zeolite#Natural_occurrence

Zeolite Group at Mindat
www.mindat.org/min-4395.html

The list of localities for the zeolite group has 10000 items.

Karl,

I think that I finally found a product that I can pick up locally, is relatively inexpensive, and appears to be already in the powdered state...sweet PDZ is the product name.  It says that it's zeolite.

www.sweetpdz.com/faq.html

[Deleted]

I have mixed the natural zeolite with the same amount of clay
and used blasting abrasive slag sand 0.09 to 0.25 mm as aggregate,
mixed all with water glass.
25 kg slag sand 0.09 to 0.25 mm are sold at Ebay Germany for 15 EUR including shipping.
Coarser slag sands 0.1 to 0.4 mm and above are sold for about 10-11 EUR.

A small amount of overaged cement served as accelerator to speed up hardening.
The result is very hard and wear resistant.

10Liter sodium waterglass about 35 EUR.
5-6 kg sodium waterglass powder (about 15-18 Liter) from pottery supply for about the same price.

If one has an old barrel and a place for a glowing fire (500 °C to 800 °C) in the barrel
one can calcine dry powder clays to obtain the required pozzolan all around the world.

[Deleted]

The sweetpdz FAG says "Premium Grade Clinoptilolite",
so it is the same mineral I have got from Ebay Germany.

[Deleted]

As natural zeolite is much denser than the flaky strukture of clay (metakaolin),
similar to porous not watertight pottery (grog) sintered at relatively low temperatures around 950-1000°C,
it can be used like grog in just add water mixtures without waterglass.

However, as zeolites are chrystaline and not vitreous like pottery the reaction
will be a bit slower.
It is only due to the high BET-surface that zeolites can be used as pozzolan,
despite the crystallinity.

Mixtures of natural zeolite, very fine clay and waterglass without additional aggregate
may cause expolosive spalling.
Pure natural zeolite with waterglass does not cause expolosive spalling
and it does not happen with natural zeolite, clay and waterglass mixtures
with additional aggregate eg. fine and coarse sand.