Trying something I saw in the FAQ with this reply as a linked topic thing to help keep the bho crc thread a little cleaner.(maybe a little late lol)
Another forum member and I have mentioned dry loading our oil into the crc using celite. Someone else mentioned silica briefly in place of celite.
@Beaker I know you have experience with dcvc at some length.
How would one go about getting their compound into their media? Is it really just as simple as add a proper ratio of media to oil, then evap the solvent? What would be a proper ratio?
Why would one choose silica over celite? I do recall you even mentioning something concerning the uses of each in a different thread.
Its as simple as diluting extract in a solvent and combining with celite and evaporsting the solvent from that. Pentane would work good for the application.
Would using ethanol as the solvent be undesirable due to the higher bp?
I’m thinking about how I’d dry it effectively now. The first thought is only use enough solvent to effectively dissolve the oil, then use a vacuum oven to lay out the wet powder thin to encourage evaporation. Without a vacuum oven available I suppose a similar thing could be accomplished in a heated vacuum chamber, but I imagine it’d be important to keep the thickness of our saturated cake of media we intend to dry fairly thin. Thoughts?
When preparing material for column chromatrography it is mixed in a solvent with equal parts silica and material then rotovap’d down until all that’s left is the material bound to the silica. They then place this at the top of the column and proceed to wash their solvent system through. I would try to stick to the lowest boiling point, least carcinogenic solvents possible for this, though you may have to get creative in your designs to make this happen efficiently.
It should work with any solvent but a lower bp is going to help you out a lot. I think it would be ideal to use butane and maybe a 2:1 ratio of celite to extract.
The concept is pretty simple. I am a rookie so rarely measure out things exact but rather just what looks good. First of all it is important to make sure your compound is as clean as it can be through previous filtering.
Then pick the most non polar solvent you plan to run in the column and disolve at room temp all the compound. All process here is room temp. Generally a 4:1 ratio of solvent to compound will do it, then pour the disolved compound onto the Celite. I use Celite because it has a low affinity for extract compared to solvent and you lose almost nothing using it as dry loaing media. Using silica will work too but generally silica sticks pretty well to the compound so it throughs off the separation a bit. Sand could be used. However the further from Celite you go the more resolution problems you get.
This was a just for fun chromatography run but not DCVC. This is flash. Same ideas though. Here you can see the Celite loaded into a PTFE stirring dish. I estimate what would make a good slushy consistency. Then after it is mixed and air dried I use a mortar and pestle to fine grind everything together while it dries.
I put the compound in the vacuum chamber to aid drying. No heat for me but a roto would be sweet. It should dry completely and to the touch feel like talcum. I show the run part way through as it is being collected. This lab was to separate coloring agents and try to get a handle on which solvent system worked best. I chose flash instead of DCVC on whim that a longer column might provide better separation.
I decided to go another route. Instead of loading oil on Celite with a solvent, I froze 56g of a darker slab, I then took 4 ss scruber pads, thoroughly cleaned them and unrolled them insto sheets of stainless wool. After the slab was frozen I crushed it as best I could and loaded the material on to the ss scrubber sheets, I tried to distribute as evenly as possible on the sheets. Then I rolled the first sheet into a cylinder and just kept rolling one onto another like a paper towel roll and then I stuffed the roll into a 18x3 column set above a filter plate with 25um paper, followed by a 3x6 spool with 100g Celine 545, 100g T5, and 50g silica60 from bottom to top with 25um paper between them, after the powders I have a 8um filter paper followed by a 2um paper. I got it set up last night, I took some pics and will post the results when I run it tomorrow.
Hopefully having it broke down like that will help it dissolve more efficiently, but a stall still might be necessary, depending on how large the crushed up compound is and how fast butane really dissolves it, but if you’re trying to get your solvent to compound ratio to 10:1 as originally suggested by @Waxplug1 a very long time ago I think that will greatly help. Just out of curiosity, would you say you lost any of your compound that fell through the ss scrubbie sheet you prepared?
Those would be my only 2 real concerns with using that method as opposed to drying it onto celite or silica. I personally don’t have any silica on hand so I’ll be going the celite route, but am very interested in how the scrubbies works out and those two previously mentioned concerns.
I suppose it could stand to reason that in practice I’d lose compound putting it on/into celite in much the fashion you might with fall-through, if you’re even been experiencing that.
I did have some fall through, but I loaded them over parchment so after I stuffed the column I just poured the dust over the ss. I plan on running 2500g of warm solvent, my tank sits at about 40psi so it should push just fine I think🤷🏻♂️
