[Terrapreta] VM composition

[ENVIPOWER]

Dear list

I joined yesterday and spent a good part of the day trying to get over the
archives. Very intense from the start - more political latter. I hope we can
stay on the technical side.

There were some discussions of PAH and other tars contaminating the soils
and waters. At the same time there were discussions on the good components
for microbiological activities.

If char has been subject to 500 ºC or more, it appears that there will be no
environmental harm in the char going into soils. On the other hand it also
appears from recent postings that Terra Pretta needs the different acids,
biooils and tars coming from lower temperature treatment.

It is known that old charcoal manufacturing places are heavily contaminated
by the tars.

If charcoal is made between 400 ºC to 500 ºC will it then
*	Be the best TP component resulting in highest microbiological
activies
*	Be the worst TP component since it contaminates the environment

If charcoal is made between 500 ºC to 600 ºC will it then
*	Be absolutely useless as TP
*	Be environmental friendly since all tars are distilled and no VM
matter is present

Can we make some conclusions here or am I simplifying too much?

I would be very pleased to receiving the literature suggested by Michael
Antal.

Best regards/Med venlig hilsen
ENVIPOWER AS

Nils Peter Astrupgaard
Snerlevej 1 DK-2800 Kgs. Lyngby
+45 4061 5600
npa at envipower.dk



-----Original Message-----
From: terrapreta-bounces at bioenergylists.org
[mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Kevin Chisholm
Sent: 8. juni 2007 00:27
To: Michael J. Antal, Jr.
Cc: terrapreta at bioenergylists.org; Goro Uehara
Subject: Re: [Terrapreta] VM composition

Dear Michael

Thanks very much!!

Michael J. Antal, Jr. wrote:
> Dear Kevin: your question is both good, and reflects widely held
> misconceptions.  A "good" charcoal with a low VM content (< 30%) will have
> experienced a temperature of 500 C or more.  Tars do not survive such a
> temperature.  Thus there are no tars present in a "good" charcoal.
> Furthermore, the VM content of charcoal is not soluble in any common
> solvent.

OK... I previously thought that VM was basically tar compounds or 
components that were still within the charcoal, because local 
temperatures were not quite high enough to drive them off. Obviously, 
with "very poor" heating conditions, the wood could still be in the 
cellulose form, or perhaps torrified. What you seem to be saying is that 
  the volatile matter in charcoal is NOT at the tar stage, but rather, 
it is wood or degraded wood components that have not been heated to the 
stage where thy have been converted to tars, or other leachable 
material. Is this correct?
> 
> The VM content is simply a measure of the propensity of the material to
> decompose when heated to a high temperature.  Charcoal contains various
> functional groups (i.e. carboxy, carbonyl, ketone, lactone, pyranone,
etc.)
> that are attached to the carbonaceous backbone structure of the charcoal
and
> are not stable at high temperatures, decomposing to form CO2, CO, CH4, H2,
> etc when heated.  These functionalities are the "VM content" of the
> charcoal.

I am embarrasingly weak on Organic Chemistry. To restate the above, 
would it be correct to say "The above functional groups are what cause 
Volatile Matter in charcoal, and they are not soluble in any common 
solvent. When heated adequately, they will decompose to CO2, CO, CH4, H2 
and tars which are swept away."

Given that the above is basically correct, and that some of the 
"functional groups" were decomposed, but not all, would there be 
"leachable tars" in such charcoal?

 From a practical standpoint, it is easy to see if I produce "poor" 
charcoal... I can see areas of unchanged wood or wood which was 
torrified or darkened. I don't need any tests to tell the batch was bad. 
If I produced a charcoal that had no original wood, or browned wood, 
such that I felt it was a "good low temperature charcoal", would it 
contain any leachable VM?
> 
> If you are interested in further details, please contact me and I can send
> you two technical papers on this subject that were recently accepted for
> publication in IECR.  One of these papers offers details of the actual
> functional group structures that compose carbonized charcoal.

Thanks very much!! I will contact you off line.
> 
> Regards, Michael.
> 
> P.S. Tars formed from biomass and cellulose are easily dissolved in
> methanol, ethanol, or acetone.  We prefer to use ethanol.

I happen to have acquired about 30 gallons of Iso-Propyl Alcohol. How 
would you rate this as a tar solvent?

Thanks very much for your help.

Kevin
> 
> -----Original Message-----
> From: Kevin Chisholm [mailto:kchisholm at ca.inter.net]
> Sent: Wednesday, June 06, 2007 12:27 PM
> To: Michael J. Antal, Jr.
> Cc: peter; terrapreta at bioenergylists.org; Tom Miles
> Subject: Re: [Terrapreta] I wish to unsubscribe
> 
> 
> Dear Mike
> 
> I reviewed the two postings you made to the Terra Preta List since its
> inception, and I wonder if perhaps you comment on the following point
> before you leave?
> 
> Michael J. Antal, Jr. wrote:
>  > Dear friends: the VM content of cellulose is about 90% but it does not
>  > dissolve in terpentine.  Need I say more?  Michael.
> 
> Would not the VM components in Charcoal most likely be tars, and
> products of decomposition of cellulose, rather than cellulose?
> 
> Would tars and and the decomposition products of cellulose that are
> found in charcoal be soluble in turpentine?
> 
> Do you know of any other common solvents that could be used to dissolve
> tars resulting in he charcoal making process, or able to dissolve other
> cellulose decomposition products that one might expect to find in
> charcoal that contained volatiles?
> 
> Thanks very much.
> 
> Kevin
>  >
>  > Michael J. Antal, Jr.
>  > Coral Industries Distinguished Professor of Renewable Energy Resources
>  > Hawaii Natural Energy Institute
>  > School of Ocean and Earth Science and Technology (SOEST)
>  > 1680 East-West Rd., POST 109
>  > University of Hawaii at Manoa
>  > Honolulu, HI 96822
>  >
>  > Phone: 808/956-7267
>  > Fax: 808/956-2336
>  > http://www.hnei.hawaii.edu
>  >
>  >   -----Original Message-----
>  >   From: terrapreta-bounces at bioenergylists.org
>  > [mailto:terrapreta-bounces at bioenergylists.org]On Behalf Of Sean K.
Barry
>  >   Sent: Tuesday, April 24, 2007 5:01 PM
>  >   To: Tom Miles; 'terrapreta'
>  >   Subject: Re: [Terrapreta] Agrichar trialled in field at Wollongbar
>  >
>  >
>  >   Hi Tom,
>  >
>  >   I believe that volatile matter in charcoal is all easily dissolved by
>  > turpentine.  Turpentine is itself one of the liquids, which are
distilled
>  > from wood (a fractional distillate).  Turpentine might however be left
on
>  > charcoal if you were to attempt to wash VM from the char.
>  >
>  >   The ASTM standard D1762 measures VM% on w/w basis weight.  It does
> not use
>  > a solvent and the actual VM is lost in the test procedure
>  >   (it evaporates).  So it will only get at the weight of the VM or VM%
of
>  > the charcoal on a w/w basis.
>  >
>  >   Maybe a procedure could be developed to wash VM from charcoal with
>  > turpentine, measure the weight of the VM which was washed out, and
> actually
>  > have the VM (in solution with the turpentine).
>  >
>  >   1) Dry a pulverized charcoal sample at 105 degrees C for some hours
(or
>  > until it no longer loses weight).
>  >   2) Add a measured (weight) amount of turpentine to the charcoal (for
a
>  > wash) in a sealed container.
>  >   3) Weigh the wash solution with the charcoal together after some
> period of
>  > washing agitation.
>  >   4) Pour out the wash solution (containing turpentine and VM)
>  >   5) Drive off the turpentine left on the charcoal by bringing its
>  > temperature up to the boiling temperature of turpentine for some
minutes.
>  >   6) Weigh the cleaned (of VM) and dried (of turpentine) charcoal.
>  >   7) The weight of the VM should then be;
>  >       weight of wash solution and charcoal (step 3) - weight of
> cleaned and
>  > dried charcoal (step 6) - weight of turpentine (step 2)
>  >   8) The Volatile Matter itself will be in solution with the
> turpentine in
>  > the post wash solution.
>  >
>  >   If the procedure was tried on duplicate samples, one with ASTM
> D1762 and
>  > one with the test procedure I proposed, then the resulting %VM
> numbers could
>  > be compared.  If they match closely, then I think it would be safe to
say
>  > that the total measurable VM can be "washed" from the charcoal sample
by
>  > using the procedure.
>  >
>  >   I think this could work.  Then the actual VM could be further
analyzed.
>  > This presumes that the turpentine does no chemically react with the VM
>  > (other than to dissolve it).  I'd welcome any comments from anyone
> who might
>  > think it won't work for any reason.
>  >
>  >   Regards,
>  >
>  >   SKB
>  >     ----- Original Message -----
>  >     From: Tom Miles
>  >     To: still.thinking at computare.org ; 'Sean K. Barry' ; 'terrapreta' ;
>  > 'Michael Bailes'
>  >     Sent: Tuesday, April 24, 2007 6:53 PM
>  >     Subject: Spam: RE: [Terrapreta] Agrichar trialled in field at
> Wollongbar
>  >
>  >
>  >     Duane, Sean, Michael,
>  >
>  >
>  >
>  >     These are good references. The ash composition of the woods,
grasses,
>  > pulping residues, sludge, etc. will carry varying quantities of
> nutrients to
>  > the degree that they are retained in the char. Through studies like
> these we
>  > know more now about the volatility of the inorganics (K, S, Cl) during
>  > pyrolysis, gasification and combustion.
>  >
>  >
>  >
>  >     I was referring primarily to measuring the volatile matter (VM)
> that is
>  > apparently available to the organisms which is what Steiner must have
> been
>  > referring to as the bio oils that are retained in the char. If a char
has
>  > 10%,  20% or 40% VM is it all available to the organisms or some
portion?
>  > How do we measure that? Is the VM that is available soluble in a dilute
>  > acid?
>  >
>  >
>  >
>  >     Tom
>  >
>  >
>  >
>  >
>  >
>  >
>  >
>  >     From: terrapreta-bounces at bioenergylists.org
>  > [mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Duane
> Pendergast
>  >     Sent: Tuesday, April 24, 2007 7:04 AM
>  >     To: 'Sean K. Barry'; 'terrapreta'; 'Michael Bailes'
>  >     Subject: Re: [Terrapreta] Agrichar trialled in field at Wollongbar
>  >
>  >
>  >
>  >     Sean, Michael
>  >
>  >
>  >
>  >     This work from Denmark seems relevant under this topic. A site
> search on
>  > the authors names indicates it has not been discussed here.
>  >
>  >
>  >
>  >
>  >
>
http://pubs.acs.org/cgi-bin/abstract.cgi/enfuem/2005/19/i04/abs/ef049739a.ht
>  > ml
>  >
>  >
>  >
>  >     Duane
>  >
> 
> 
> 
> 


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