So do you also have an infinite supply of newspaper?
I've now done two 1 kg batches and have made a couple of time-saving
changes to the procedure, but I'm still facing a couple of large-ish
problems as I contemplate doing a 10kg batch:
1) Newspaper is almost unobtanium around here--I haven't read a hardcopy
newspaper in a couple of decades, my neighbors don't get them, and my
local supermarket no longer sells them. I did manage to scrounge enough
for two batches by locating some street-vending boxes of freebie
neighborhood papers, but that won't scale up.
2) The space required for the drying stage of a 10kg batch is going to
mean devoting either my entire kitchen floor or a large part of my
garage floor for the better part of two days.
(I did make a vacuum dryer using my shop vac, a 5 gal pail and a 1gal
water bottle along the lines shown by Dyanko Chernev, and that sped
things up considerably, but didn't fully dry the KN, so I still had to
do some paper-drying.)
Can you provide some details on how you dried your 10kg batches?
Thanks,
--Steve
On 2/14/24 12:28 PM, Richard Nakka wrote:
" /...but I can see the utility of an infinite supply of very cold air for this operation/"
Not only that, but the outdoor freezer is of infinite volume, definitely a luxury considering how stuffed our indoor freezer is :-)
R.
On Wed, Feb 14, 2024 at 2:19 PM Steve Peterson <dmarc-noreply@xxxxxxxxxxxxx <mailto:dmarc-noreply@xxxxxxxxxxxxx>> wrote:
Thanks for the responses, guys. Very helpful.
Richard: I don't think I've ever envied you your wintertime
temperatures, but I can see the utility of an infinite supply of
very cold air for this operation :-)
(I am now eyeing my 12 qt stock pot which, with only minor
rearrangement of shelving, will fit in the freezer.)
--Steve
On 2/14/24 7:42 AM, Richard Nakka wrote:
Steve...your suggestion of using an aluminum container for
cooling is a good one. From my experience, that speeds up
cooling. I do my recrystallization in winter. As such, the
container is placed outdoors in a location where there is a
strong breeze. The convective effect greatly speeds up cooling.
Is it feasible to place a battery powered fan in your freezer to
achieve this effect?
We make sure and regularly stir the crystals as cooling takes
place. Else you end up with a large single mass of crystals that
is hard to deal with when washing. This may not be such a factor
with a small (1kg) batch, however, we recently recrystallized
20kg of 'dirty' KN, split into two batches. A large lump of
crystals of that size is a problem.
Richard
On Wed, Feb 14, 2024 at 8:08 AM Steve Peterson
<dmarc-noreply@xxxxxxxxxxxxx
<mailto:dmarc-noreply@xxxxxxxxxxxxx>> wrote:
I'm about to try synthesizing KNO3 according to method 4a here:
http://www.nakka-rocketry.net/knsyn2.html
I notice that two of the steps (4 in total since each is
performed
twice) seem to be particularly time consuming (in clock time,
not labor
time), namely, the chilling to -10C (and -5C) and the drying
steps. I
don't mind spending all day doing this, but I'd like to get
more than
700g out of the ordeal, so I've been wondering if there
aren't some ways
to improve throughput.
One would be to increase the batch size, but that seems
problematic.
Another is to do multiple batches in parallel, which would be
easy for
the drying steps (just use more cookie sheets and
counter-space), but is
harder for the chilling steps since freezer space is limited.
A third method would be to chill faster. The directions
mention using a
poly container for this step, but I'd think an aluminum one
would help
to speed up the process (slightly). But I was thinking a cooler
containing dry ice might get the chilling time down to ten
minutes or so
(just speculating--haven't done any calcs/measurements).
But then I wondered if maybe the long chilling time was a
feature not a
bug in that maybe the crystals just take a certain amount of
time to
form and perhaps speeding up the process would hinder their
growth and
thereby limit the yield. Any experience/thoughts on this?
Likewise, I was wondering if the mixture should be stirred
during the
chilling process (to even out the temperature of the liquid)
or left still.
Thanks for any help,
--Steve
