[Terrapreta] Fwd: ammonia and charcoal

[Gerald Van Koeverden]

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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