So I bought a vacuum chamber…

[Rabidreject]

Hi guys;
I bought something iv been wanting/ needing for a while to finish my workup of DMT from tryptamine - a vacuum chamber/dessicator.
To be honest it was a double whammy because it came with a pump and whatever else it needs to work but yeah I’m interested in the pump.
It says it comes with some oil but I’m wondering, do they just work off of mineral oil, or do I have to buy special ‘pump oil’?

Its just a rotary vane pump, I doubt it will be all that powerful as there are definitely bigger ones out there so not super sure how useful it would be for vacuum distillation but really any drop in temp could be useful at some stage.

I do intend to get one of those 1/4” screw connector cables, that I can then attach to a 3 way adapter with a mm/hg manometer on it instead of whatever those car guys like, or whatever those AC guys like…

Anyway, iv done this RXN twice now and simply need a vacuum dessicator to turn it “to a ‘waxy - scrapable’ substance…”

Man I wish I’d started with PEA’s. Oh well! What gets you interested in organic chem, gets you into it I guess….

 

[Osmosis Vanderwaal]

It takes special oil, if you put the wrong oil in it , it'll die fast. A single vane rotary pump can pull enough vacuum to boil water at freezing temps, the biggest issue is the oil . All the air you vacuum goes through the oil. A diaphragm pump is a lot better because it doesn't take oil. The rotary vane is ok for many things like vacuum filtration, dessication ECT. But distilling with it is a pain

 

[Rabidreject]

Yeah I actually have a small diaphragm pump anyway but I wanted a pump that can be left on for long periods of time and due to the fact that when I bought the prior oil’less one, they told me it could only really be left on at full vacuum for like 30 mins before over heating - great for vacuum filtering but not so great for RXN’s and I was hoping to be able to use this pump for that mainly….

It seems I’m doing something wrong anyway! Ha

 

[Rabidreject]

It’s okay. It came with some oil - now I know, that’s cool.
hey am I doing something wrong or does my vacuum chamber / pump just not pull enough of a vacuum or are you suppose to have a desiccant inside at the same time? Like silica balls that change colour, or would you only use them for getting water out of things, which I am not.
Dang it, I should have just bought a vacuum dessicator made for an actual lab and a pump seperately…
I am trying to turn the oil left over from re-x’ing the workup from the tryptamine -> n,n-DMT synthesis I performed but so far, it’s not hardened up to a waxy, scrapable substance but I did get some crystals around the edge of the beaker.
Should I try to re-x from this? Or am I simply doing something wrong or does it need longer In there under a vacuum.

When I first put the oils obtained from the workup in there, they did start bubbling, however, it just won’t harden and x’stalise to any major degree

Oh well. Least it’s Amazon and so return it super easy haha!

 

[Rabidreject]

This is where I’m at and it’s tantalisingly close!

 

[Rabidreject]

 

[Rabidreject]

Omg what the hell happened!!! Haha I access this site mainly on my phone and it doesn’t work so good!

 

[Rabidreject]

But to be fair, that is about as annoying as it is to have a load of oil you can’t seem to crystalise!

 

[Rabidreject]

Ohhhh shit okay, your suppose to allow some air in and out and simulataneously run the pump.
That makes more sense…
Okay so I’m using a vacuum chamber designed for getting the air out of epoxy resin, among other things, so I am assuming, I need to find the sweet spot with the ‘out’ valve in order to keep the vacuum going at the same rate air is flowing through.
I’ll be interested to see if this actually works. I realised I was mistakenly thinking about normal desiccant chambers which you may well add something like those silica balls - if there was any water in what I was trying to remove and there obviously isn’t as I dried the solvent at an earlier stage.
Either that or just leave it running with it fully closed…for a longer period than I did.
The synth (again) doesn’t specify.
Gah this is so annoying!

 

[Osmosis Vanderwaal]

You put dessicant in the bottom, like epsom salt or calcium chloride, and then what you are drying, pull max vacuum. Put a lamp or other MILD heat source like 50°C. If your chamber has a petcock you can just pull a vacuum, shut the petcock and turn the pump off

 

[Osmosis Vanderwaal]

You should really get a cold-water trap right away, or make one. It's basically a bong and it sets it ice water and condensed water vapor coming to your pump and the water dissolves some acids bases and noxious chemicals like ammonia. This stuff will eat that pump. I distilled something that was excess HCL and the next day it was frozen and inside it was 100% rust. If you know you are making ammonia or methylamine gas. You can put some HCL in the trap and catch that gas as hydrochloride salt or just save the water for sal ammoniac or methylamine in water

 

[Rabidreject]

Ah yes, I actually have a ‘cold trap’ I was wondering if I should be using that as well!
OK now it seems like I am getting somewhere!
Lol I guess it is basically a bong…nice descriptor!
Okay that makes WAY more sense - for some reason I just assumed it was the vacuum that was essentially making whatever it left over into a gas but didn’t think about having anything in there to act as a dessicant in order to actually absorb the gas….
Okay, I shall try again today and yer iv got two ball valves on the top connected to a vacuum gauge (manometer?)

Can I make normal epsom salts anhydrous by melting and driving off any water in a frying pan or something? I do have anhydrous Mag Sulfate but not a huge quantity…
I assume I can’t use normal Epsom salts but I could be wrong…

 

[Osmosis Vanderwaal]

Sure. Plain epsom salt spread out on cookie sheets, 350-400f for 2 hours. After 15 minutes break it all up, and again at 30 minutes. Check it at 1 hour for clumps. If you don't do that it turns so fucking hard that a hammer won't even break it . The neat thing about epsom salt is that magnesium sulfate is typically a heptahydrate, meaning every molecule holds 7 water molecules.

 

[Osmosis Vanderwaal]

What vacuum does the gauge say the pump is pulling? It should pull 28"w.g. or -700torr or -0.9 barr unless something is wrong with it

 

[Rabidreject]

Oh shit I didn’t know what that actually meant when people said that before or I’d read something like someone would say it’s a heptahydrate and I wouldn’t know the knock on effects of that. Sure you can work out 7 and something to do with hydrogen but I didn’t realise the implications.
I just spread some of my already anhydrous mag sulf in there and yeah it IS doing A LOT more but I do have to leave the pump on or I’m losing pressure even with both valves shut, does that mean I have a leak in the place the pressure gauge and everything is screwed into?
I must admit, I did wonder if I should have added another washer, I shall do so as the thread didn’t go all the way down. Ah it’s hard to explain but an easy fix.
I mean, the jar that has the x’stals already around the edge does seem to be more active than yesterday.
Also I did have a look at it this morning, and to be fair, there was a section of the oil that was just starting to set…

I honestly hope this is the FINAL thing I needed to work out to finish this blooming synthesis!!! I KNOW there will be more DMT in the oil before this that I re-f’d from.

I was thinking - if this fails, it may be time to re, re-x this fucking thing haha

ah well, we learn from adversity right?

 

[Rabidreject]

Yeah -1bar, it’s actually staying there quite well now to be fair and it did stay there last night for a long time as well (even though it didn’t do much as I forgot the desiccation part of the, VERY MUCH, name implied action!!)
It looks like it is doing a lot more now to be fair - at first it looked like I had to keep the pump running to getting bubbles but it doesn’t look like i do.
Does it make sense to anyone that, the one where I added a little bit of chloroform to the heptane before final re-x, is bubbling less (maybe not at all) than the one that I used pure heptane to re-x with?
Surely I don’t need to set up a cold trap just to run this pump for the 5 mins MAX I have to, to get it to pressure? Should I disconnect it and run it disconnected for a couple seconds to get rid of any residual remaining hydrocarbon inside it?

 

[Rabidreject]

One last question for now…how do I know I need to replace the anhydrous mag sulf once it’s no longer anhydrous? Will it start clumping as it does when I’m solvents? Surely it won’t just start moving around the place iv put em?
So can someone explain what I am actually removing here? Am I removing water from the final oil or am I removing residual heptane? Or am I removing both?

If you don’t know the story, I re-x’d the final oil using heptane as per the synth and then instead of evaporating (as I didn’t get any more after testing last time when I freeze precipitated and then I evaporated the heotane - just to check if there was any DMT left) and was left with crystals but mainly an oil (again as per the synth) and now it’s in a vacuum desicattor.
As I said before, I used heptane mainly but I did also decided to try 9:1 heptane:chloroform as well which seemed to only give up an oil upon getting out of the freezer.

So what, is this removing the water molecules that either I missed when I dried the solvent over the same anhydrous mag sulfate? Or even the ones it may have taken up since then? Confused…. surely it’s got to be water if mag sulfate has ramped it up a notch…

 

[Rabidreject]

I couldn’t work out how to edit my previous post and turn it into one.

Okay, so I set my mantle to 50c/ put the probe in between the vacuum chamber and the mantle and sprinkled some anhydrous mag sulfate and then pulled a vacuum.
Then I watched it….it bubbled more than yesterday for sure but am I correct in thinking once I stop seeing bubbling I pull it off the top of the heat source and let out the vacuum? Oh, I did also try adding more magnesium sulfate into the container and then pulling another vacuum to make sure it isn’t because that has become hydrated.
I will be interested to see if this finally turns it into the waxy scrapable substance I should have….

 

[G.Patton]

Hi, you can read about that in technical description of this pump.
What do u mean -1 bar? It's impossible to reach reassure lower than 0.
Agree
What do u mean?
https://bbgate.com/threads/decantation-gravity-filtration-and-liquid-transferring.566/ there is video tutorial

 

[Osmosis Vanderwaal]

It's extra hard to reach pressure in a vacuum .