[Terrapreta] Fwd: ammonia and charcoal

[Gerald Van Koeverden]

Edward,

I'm not sure I understand what you are saying.

The only 'thermal' treatment my biochar got was to sit around in open  
barrels outside.

At first, I thought it's now hydrophilic nature might be just a  
result of being oxidized by exposure to air over one year.  But I've  
also tried a sample of dry biochar - a year old and never been wetted  
- but it is still 'resists'"water infiltration when placed side by  
side.  It is still hydrophobic.

Though I can't claim scientific validity, it seems that biochar  
saturated in water over time (whether one hour or 6 months?) does  
change its relationship to water.

As to Brain's comments:

I haven't tried to measure how strong the water absorption is -  
whether more or less than other soil constituents.  However, it does  
incline me towards the idea that water can move in and out of water- 
conditioned charcoal quite easily, providing a mineral/nutrient  
transport system in and out of the particle.

If you make a pile of water-conditioned biochar and make a depression  
in the center and fill  that depression halfway up with water, the  
water is sucked right up to the top of the pile.  But I can see that  
a solid block of charcoal wouldn't do that. Of course,  the xylem of  
the original wood has been blocked by the process of charring.  But  
moreover, In a pile of biochar, the spaces between particles might  
serve as the capillaries which pull the water uphill?

The question then is why does this happen in conditioned char but not  
in un-conditioned char?  Is only the surface of the char particle  
effected, or does the change extend to the pores?

Gerald


On 9-Feb-08, at 11:51 AM, Edward Someus wrote:

> Gerrit/Brian
>
>  RE Charcoal is a strong hydrophobic
> YES, when the char is not properly produced for biotech  
> applications and containing tar residuals you get this phenomens.  
> The hydrophobic effect is the property that non-polar molecules  
> tend to form intermolecular aggregates in an aqueous medium and  
> analogous intramolecular interactions. This is why the fresh char  
> first adsorbs water than release it. Repeated thermal treatments  
> may change some this character, but in the industrial application  
> reality, there is no economy to thermally treat char again.
>
>
>
> Sincerely yours: Edward Someus (environmental engineer)
> Terra Humana Clean Tech Ltd. (ISO 9001/ISO 14001)
> 3R Environmental Technologies Ltd.
> ADDRESS: H-1222 Budapest, Szechenyi 59, Hungary
> TEL handy:  +(36-20) 201 7557
> TEL / FAX:   +(36-1) 424 0224
> TEL SKYPE phone via computer:  Edward Someus
> 3R TERRACARBON:   http://www.terrenum.net
> 3R CLEANCOAL ENERGY: http://www.nvirocleantech.com
>
> -------Original Message-------
>
> From: Gerald Van Koeverden
> Date: 2008.02.09. 15:51:45
> To: Terra Preta
> Subject: [Terrapreta] Fwd: ammonia and charcoal
>
> Fresh biochar exhibits strong hydrophobic properties.  But biochar  
> that has been sitting around in the open exposed to rain is totally  
> opposite.  When I dry this biochar out, and then re-expose to  
> moisture, it soaks up water like blotting paper.
>
> This change in physical property must be a reflection of chemical  
> changes - at least on the surface of the pores.  Has anybody seen a  
> study of how charcoal/biochar changes chemically over time,  
> comparing the changes in wetted versus dry-stored.
>
> This could be important, eg in using it as an ammonia absorber in  
> making compost.  Charcoal that has been soaked first in water,  
> might have a very different ability to act as a nutrient "sponge."
>
> Gerrit
>
>
> Begin forwarded message:
>
> From: Gerald Van Koeverden <vnkvrdn at yahoo.ca>
> Date: February 7, 2008 10:41:00 PM EST (CA)
> To: terrapreta Preta <terrapreta at bioenergylists.org>
> Subject: Fwd: ammonia and charcoal
>
> The nature and strength of the electrical charges inside the  
> charcoal particle, might also be important for anchoring  
> microorganisms in it as a microhabitat.  For example, bacteria tend  
> to have a negative electrical charge.
>
> Begin forwarded message:
>
> From: Gerald Van Koeverden <vnkvrdn at yahoo.ca>
> Date: February 7, 2008 5:04:55 PM EST (CA)
> To: terrapreta Preta <terrapreta at bioenergylists.org>
> Subject: Fwd: ammonia and charcoal
>
> to follow up on ammonia absorption in charcoal...
>
> it's interesting to note that there is no direct relationship  
> between charcoal porosity and ammonia absorption.  In fact, the  
> absorption of low temperature-made (400 degrees) bamboo charcoal  
> treated with a dilute sulfuric acid is twice that of activated  
> charocal which has a pore surface area eight hundred times greater.
>
> http://jhs.pharm.or.jp/data/52(5)/52_585.pdf
>
> Gerrit
>
> Begin forwarded message:
>
> From: Gerald Van Koeverden <vnkvrdn at yahoo.ca>
> Date: February 7, 2008 3:51:02 PM EST (CA)
> To: terrapreta Preta <terrapreta at bioenergylists.org>
> Subject: ammonia and charcoal
>
> Could chemical interactions between ammonia and charcoal be the  
> initial key for how charcoal is gradually transformed into that  
> found in terra preta?
>
> "Australian researchers have discovered a cheap and simple way to  
> make sheets of carbon just one atom thick.
> Their finding has implications for a range of developments from  
> solar cells to bionic ears.
> The sheets, known as graphene, normally stack together to make the  
> kind of graphite used in pencils.
> But when separated, graphene sheets have extraordinary electronic,  
> thermal and mechanical characteristics, says Gordon Wallace from  
> the University of Wollongong in New South Whales, Australia.
> "People have known that if you can separate sheets of graphene from  
> graphite you can get some pretty interesting properties," he  
> explained.
> Most researchers thought creating these sheets in a cost-effective  
> way was an insurmountable challenge, due to their strong tendency  
> to clump together. But in the journal Nature Nanotechnology this  
> week, Wallace's team shows stopping the sheets from aggregating is  
> actually a fairly simple matter.
> The Australian team did not use chemical stabilizers to keep the  
> sheet apart. Instead, they used water with some ammonia added to  
> increase its pH value, making it more alkaline.
> "It's actually a really simple discovery but with fairly  
> significant implications," Wallace said.
> "It's a matter of understanding that simple chemistries can be  
> applied to graphite sheets."
> Increasing the pH of the water raises the electrostatic charge on  
> the graphene sheets, he explained, making sure they repel one  
> another instead of clumping together.
> This low cost approach raises the possibility that scientists could  
> produce large amounts of stable graphene that could be used in a  
> range of settings.
> "The very unusual electronic properties of graphene sheets means  
> they could be used in solar cells or new battery technology," he  
> said. "Because of the biological affinity of carbon, they might  
> also be useful as electrodes for a range of medical bionic devices  
> such as cochlear implants."
>
>
> http://dsc.discovery.com/news/2008/01/29/nanotech-carbon.html
>
> Ammonia and water - being the main ingredients in urine - could  
> easily have been added to charcoal by native Amazonians.
>
> It is apparent that ammonia changes the chemical nature of carbon  
> molecules.  To effect charcoal, it would need transform only the  
> innner pore surface area of the charcoal particle to dramatically  
> change its CEC, without affecting its overall physical structure.
>
> This afternoon, I added a saturated solution of ammonium nitrate to  
> biochar to compare with a control of pure water mix.  Once I let it  
> sit for several days, I'll dry out the samples and then see if I  
> can see any difference in how they re-mix with water.
>
> Unfortunately, I don't have any lab equipment to then test to see  
> if the CEC has changed.  I'm trying to think of simple tests I  
> could do to find out what, if any, properties have changed, for  
> example:
>
> a)  putting a large drop of water adjacent to the pile of char to  
> see how quickly the char sucks it up as a test to see whether its  
> hydrophobic properties have changed.
>
> b)  using the two samples as a filter for various aqueous solutions  
> to see if there is any difference in what they filter out of them...
>
>
>
>

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