subsecret - 21-8-2013 at 17:57
As you probably deduced from the title, this thread is about extracting or pulverizing organic materials prior to extraction.
I came across several documents about organic extractions...that used liquid nitrogen to freeze the sample prior to crushing. Here is a reference to
the idea:
http://www.sciencemadness.org/talk/viewthread.php?tid=1496
I'm sure we've all seen the "Rose in Nitrogen" demonstration in person or through a video. I understand that most of us don't have access to liquid
nitrogen, so I decided to propose a different idea.
I'm sure that many of you have also
heard of "Poor Man's Liquid Nitrogen" which is basically alcohol chilled by dry ice. CO2 sublimes at -78 C, which would be plenty to
freeze any organic matter. Here's a video of the concept:
http://www.youtube.com/watch?v=c9sOnuPUVHk
Because the alcohol will not be as cold as liquid nitrogen, more freezing time will be needed. The organic material could also be frozen, crushed,
frozen, and crushed again. This could be repeated several times. The alcohol would soon evaporate from the organic material, so separating the alcohol
would be no problem.
The alcohol should be as dry as possible. Adding dry ice, letting the mixture sit for several minutes, and then decanting off the alcohol would serve
to dry the alcohol by freezing all of the water.
As far as I know, multiple freezes and pulverizations after freezing in chilled alcohol is an untested experiment. I'll test it if I can get my hands
on some dry ice...
Just a concept idea, but I hope it helps...
bobm4360 - 21-8-2013 at 21:12
Most welding supply houses can get LN2 in small (gallon) quantities, if they don't already stock it. As a bonus, they stock various diameters of
stainless steel rods for making lab tools and aids!
Regards,
Bob
subsecret - 22-8-2013 at 17:34
That's really neat. I'll have to find a welding supply house near me...
How do you recommend transporting the nitrogen? Could I make a Dewar from PVC pipe?
bobm4360 - 22-8-2013 at 20:10
Thrift-store Thermos bottles with stoppered openings, ie, cork. DO NOT use screw-type lids!!! Or, you can just leave the top off if you have a
well-ventilated means of transport, and a way to prevent and contain spills.
Cautions:
1) Contact with cryogenic liquids is equivlaent to third-degree burns-instant tissue death and damage below the skin.
2)The bluish liquid on top of the LN2 is liquid oxygen that has condensed from the air. Decant it outside where it won't splash.
Regards,
Bob
subsecret - 23-8-2013 at 13:10
Ouch! The cold alcohol is possibly more dangerous, as it won't form a vapor layer between skin and itself. Also, cold alcohol is sticky.
Fantasma4500 - 24-8-2013 at 05:05
is alcohol sticky? i thought i read some thread on here that alcohol without water was exactly not sticky..? (:
'NurdRage' on youtube demonstrated how its possible to put your hand in liquid nitrogen, only so that others wouldnt need to do it ofcourse!!
remember long time back me and a classmate got hold of a lighter refill..
if you emptied it fast enough you could get the butane out in liquid form, now consider having this set up in the cold winther months, with additional
cooling, outside (!!!) you can surely get to freeze some things down well with liquid butane
im not very sharp on organics, but i suppose butane could act as a solvent, i know it has been used to extract pure THC
(yes, there you go, they blew up the house because they were so smart to light a joint when cooking it.. again this isnt something you do inside)
always wondered how much it would actually take to build something that would be capable of compressing air enough to make it liquid, and from there
keep it compressed, liquid and super cold, to then extract liquid oxygen from the air (:
subsecret - 24-8-2013 at 06:36
I'll have to find that thread...Because nitrogen is a gas at room temperature and alcohol is a liquid, nitrogen will have a stronger tendency to
evaporate under slightly warm conditions (human skin). This will result in the Leidenfrost effect, preventing burns. I suppose that the alcohol would
wet objects better than liquid nitrogen..
SM2 - 27-6-2014 at 06:31
My experience is that the contrast between a typical hand temperature and LN2 is so great, that the Ln2 never really contacts the hand by doing quick
soaks. As long as your hand is room body temp., you can just dunk it into pure LN2 for a sec, and pull it out - no problems. I can imagine a
scenario where a warmer liquid (a liquid butane or freon) would hurt much more, not being cold enough to be repelled by your room temp. hand.