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Post by Deleted on Aug 30, 2016 18:12:47 GMT -8
If the Minspar Feldspar works (it should) you can have a relatively inexpensive mixture with Soda Ash and lime or cement. No waterglass required with lower aggregate content. Diatomaceous earth can be used as powder, but is not required. Undissolved diatomaceous earth will create pores. You need 1.33 times more soda ash than sodium hydroxide. Sodium carbonate react with calcium hydroxide Na2CO3 + Ca(OH)2 → CaCO3 + 2NaOH chemiday.com/en/reaction/3-1-0-383Even with Mullite 200M a mixture would be significantly cheaper as your calculation. If you use a paint mixer at high speed for a mixture of Mullite 200M, soda ash, quick lime and a foaming agent, you should be able to make a lightweight foam. Not sure if the Minspar Feldspar would be reactive enough. West Michigan Clay 3765 Lincoln Rd, (M-40) Hamilton, MI 49419 USA Phone +1.269.751.5839 www.westmichiganclay.comCheaper. Has no very fine grog. Grog starts at fines to 48 mesh ~ 0.3mm Mullite, #35 Mesh ~0.5mm |
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Post by firewatcher on Aug 31, 2016 8:33:49 GMT -8
From Red Devil directly 4.5 lb for $12.99. Thats enough for at least 6 liters which should suffice for more 20kg dry mixture. www.reddevil.com/index.php?l=product_detail&p=868At Ebay 4lb for about $10 + about $5 shipping. Outside of the riser are not ambient temperatures but many hundred degree Celsius. My thin test samples can maintain a much higher temperature difference at ambient temperatures, than the temperature difference of the gas from the inside to the outside of the riser. I cannot break one of the 17mm plates with my hands once fully hardened. Requires an hammer or throwing on a concrete floor to break one. I re-did the math...using the Red Devil product (instead of mixing lye and silica gel bought separately), it reduced the cost by $40/cubic foot. This puts me in the range of $70/cubic foot of geopolymer refractory.
Most commercial refractories that I'd seen on-line when I looked into them were about $75 per bag. Each bag cast only a volume of 1/2 cubic foot and were only rated for "indoor" use. The "outdoor" versions were slightly more expensive. My point to this comment is that at the present prices for the products used in the mix, it should cost 1/2 as much as if commercial refractory was used.
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Post by firewatcher on Aug 31, 2016 9:01:49 GMT -8
Washed and purified diatomaceous earth as used for swimming pools is pure silica (SiO2). It can be dissolved with lye to make waterglass. Pozzolanic activity refers only to the ability to react with calcium hydroxide. Geopolymerisation needs some aluminosilicates. You always can place some tin cans with clay powder in a campfire or barrel kiln, to get calcined clay and even use the ash. Natural zeolite is used for swimming pools too. Also you may try at: Rovin Ceramics Inc 253 Dino Dr, Suite A Ann Arbor, MI. 48103 rovinceramics.com/Contact: 734.424.3345 orders@rovinceramics.com They sell among other things: Mullite grog 200M, very high alumina content. Minspar Feldspar 200M, gets down to, 65 cent from 50pound and 50 cent from 100 pound upward.. Soda Ash (Sodium Carbonate). Calcium hydroxide can be used to get the sodium hydroxide from it. 50 pound upwards $1.00 Together with diatomaceous earth that is all you need for a binder. In the spirit of trying to reduce the cost of the waterglass further, you mentioned that diatomacious earth can be used to make it...what ratio of diatomacious earth to lye should be used. I'll determine some pricing and find out if this will reduce the price of a waterglass mixture even further than using the Red Devil product. |
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Post by Deleted on Aug 31, 2016 9:24:55 GMT -8
Purified diatomaceous earth is pure silica,
also in the same ratio as with silica gel.
Soda ash is much cheaper as sodium hydroxide but is weaker and needs 1.33 times more than sodium hydroxide.
Could be either mixed directly with diatomaceous earth,
or sodium hydroxide solution could be gained from it with help of calcium hydroxide.
106g Na2CO3 + 74.1g Ca(OH)2 + water.
The insoluble calcium carbonate precipitates and settles to the bottom.
The remaining liquid is sodium hydroxide solution and can be poured off.
The solution contains 80g NaOH
minus a small amount remaining with the precipitated calcium carbonate.
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Post by jimfritzmi on Aug 31, 2016 16:09:00 GMT -8
Karl, I have a question for you. I've been following this and your other geopolymer threads with quite a bit of interest for the last couple of years. You just happened to mention West Michigan Clay which happens to only be a few miles from me. Using them as a source as I have worked with the owner before on a project, could you possibly suggest a mixture using their product line and other commonly available items for me to get started with. I know this sounds odd, but this has been my tipping point. As you read this I am clearing a spot in the garage to start my experiments and I await your response with baited breath. Thank you in advance.
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Post by Deleted on Aug 31, 2016 16:55:17 GMT -8
What may be useful from West Michigan Clay in no paricular order:
BENT Bentonite, if it is the greenish magnesium containing kind it could be preactivated with acid,
else if can be used as a thickener.
Smaller amounts of some kind of ball clay, as ball clays have the smallest particle size.
GROG-FINE Fine Grog (48 Fines), do not know if it has enough fines for geopolymerisation.
The nice thing about grog: can be used without waterglass.
The three stone flours need to be tested if they are reactive enough.
G-200-HP Feldspar - Potash G-200
MINSPAR Feldspar - Soda spar, Minspar 200
NEPH-SYE Nepheline Syenite—A270
SILICA-325 Silica, Flint #325 Mesh, could be used to make waterglass,
but not as easily sobluble like silica gel.
SOD-ASH SODA ASH, DENSE, Lye.
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Post by jimfritzmi on Sept 1, 2016 14:32:30 GMT -8
Thank you Karl, that gives me more than enough information to be dangerous and busy. LOL
I'll head over this weekend and get some samples of the flours. As for the soda ash, wouldn't I need to increase the amount in the mixes a great deal as it's not nearly as strong. Though I may be wrong it has been decades since I made soap.
Thank you again for be such a huge part of my education on geopolymers. By the way, I just found out that the electric generating station not that far north of me is a source for type "C" fly ash. I'll have to give them a call though as from what I just read Headwaters Resources sells it. I'm hopeful I can get some without ordering a ton. :-)
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Post by Deleted on Sept 1, 2016 15:10:31 GMT -8
jimfritzmi above I have described how to get sodium hydroxide from soda ash.
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Post by Deleted on Sept 2, 2016 10:04:21 GMT -8
I have got the cheapest bird sand from a supermarket.
It is very fine quartz sand similar to sand in the dunes of a beach,
mixed with stomach stones, nutrition minerals and very little anise oil
to cover any stink the birds may generate.
The larger particles have about the same size as my slag sand.
To get rid of the unwanted material I have sieved it through a nylon.
I have made a 4/1 ratio mixture quartz sand/ zeolite and mixed it
with the usual amounts of lye, cement and waterglass.
After curing and drying I have made a reverse side test.
As expected the reverse side temperature rised much faster
than with the slag mixtures and got much higher.
The sample showed signs of melting at the surface.
But worst of all a small crack occured.
It is the only cracked one of many samples undergoing this test.
The crack hints to the biggest weakness of free silica,
the many temperature dependat crystall phases,
each occupying a slightly different amount of space.
The outcome, which had to be expected: Do not use quartz sand.
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Post by Deleted on Sept 6, 2016 4:00:26 GMT -8
Karl I managed to find this material called prophylaxis. See the spec sheet  Can it be used to create geopolymer as it is without other additives? What do you think? You could try to preactivate it with organic acid. As it is a very fine layered aluminosilicate with high alumina content it will very likely work like a charm. BTW you said you want to let perfom some strength tests with your geopolymers. Any results ? |
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Post by firewatcher on Sept 6, 2016 14:11:54 GMT -8
Update on two pucks that I "fired" last night in a camp fire:   Both pucks i was able to break with my hands (although it was not easy...and there were a few places in each puck where I noticed some very fine micro cracks). Looking at the pic of the broken pucks, the one on the left was made withe the following recipe: 100g perlite powder 35g fire clay 500g slag 3/4 cup 2L concentration waterglass 50g hydrated lime Again looking at the pic of the broken pucks, the one on the right was made with the following recipe: 100g zeolite powder (probably not quite as fine as it should have been) 35g fire clay 400g slag 50g hydrated lime 1 cup 2L concentration waterglass (I over did it when adding the waterglass...I had only planned to use 3/4 cup) |
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Post by Deleted on Sept 6, 2016 14:25:41 GMT -8
You need only 10% hydrated lime by weight of the pozzolan plus clay,
13.5g in this case, to work as an accelerator.
More lime or cement may cause micro cracs and makes the result more brittle.
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Post by firewatcher on Sept 6, 2016 14:37:45 GMT -8
Of note: It's not really visible in the picture, but the zeolite puck had a 3-4mm thickness in the center that i could still slightly press my finger nail into if I pressed very hard...it may not have completely cured.
Each puck was 1 inch thick, 5 inches in diameter.
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Post by Deleted on Sept 6, 2016 14:53:44 GMT -8
Of note: It's not really visible in the picture, but the zeolite puck had a 3-4mm thickness in the center that i could still slightly press my finger nail into if I pressed very hard...it may not have completely cured. Each puck was 1 inch thick, 5 inches in diameter. That shows the high insulation properties, if it is still not completely cured in the fire. Likely because the zeolite is not quite as fine as it should have been. Even after drying the geopolymer will gain some strength over time. A small additional amount of lye will let it cure better. |
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Post by firewatcher on Sept 6, 2016 17:23:31 GMT -8
Is there a quantatative amount of additional lye (ratio of one component to another) that would generally get one near an ideal amount?
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