It would depend heavily on how well you devol your feedstock. It’s probably worth it if you don’t devol in a reactor
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Once the diffusion oil soaks it no longer works. If you want to use diffusion you need to ensure your vapor pathway is dry and nothing is getting past your main hardware body. I secret with diffusion is using large pumps, high end oils, and super accurate gauges with immediate responce on screen. Also sweep tech helps with pulling all wet vapors out of system with a wet pump first.
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Is that why people are using those high com boosters? If I’m deeper in vac should I turn my evaporator temp down?
What pumps are beeing used now ?
Oops yust saw your running a Edwards
How much distillate running per hour and what s your vacuum depth at now with the Edwards ?
The boosters are more for moving molecules down when doing dry work. The diffusion is another monster on its own. It doesn’t want a booster nc they the booster will splash the oil.
What vacuum level should I turn on at? Currently 400 micron not working.
Where are you reading you vacuum? 400 should be well low enough. What pump?
Edit: also what are you using to hit that pressure/is that all you’re able to pull roughing in? If so you may be leaking faster than the diff can pull
Reading just past the cold trap. I don’t think I have vac leaks using ax-65 diff on e2m28 under no load I’m pulling like 150 micron and it still doesn’t work.
When you say “sweep tech” are you referring to dosing the vacuum inlet with inert gas or using inert gas on the ballast?
Yeah manual says it should run fine anywhere below 500 mtorr. 150 mtorr with a dry still on an m28 sounds like a good bit of leakage or your pump needs attention
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During Distillation the sweep gas enters above the fluid on flask.
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I assume what he means because the clarification wasn’t quite clear is that when you rough down, there’s still atmosphere in the flask even when the pump stalls. In order to push that last bit of atmosphere which is frequently water vapor, you can intentionally leak a little dry gas directly into the boiling flask to push that water vapor out.
Did I get that right @spdking?
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Is the heater working. On the diff ?
Those heaters go bust quiet often ?
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Yeah it’s hot, it just won’t pull vac.
What is your diffusion opperation process. Those pimps have a very exacting Sop to operate. What oil did you use. Dod you clean the inside of the pump with acetone and sterilize it (finger print oils can prevent diffusion from working right on startup) , and or did you assemble the diffusion pimp and run it under vacuum for 4-6 hours and watch the guage dip.
You need to tell us what you’ve done exactly. Diffusion is a analog style process. Only works one way. Of you didn’t install it right and or run it isolated to test it you won’t be able to run diffusion on your hardware. Also you should be using multiple pumps for scaling the vacuum range to diffusion.
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Dry ice is fine. Diffusion is only for doing main body removals from the residue. Dont use it on your terp strips
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I’m curious if anyone has any idea how much oil to put into a diffusion pump? I could email Lab1st, but I figured I’d probe here first. The unit is on a stainless SMD-01. I have some pictures I took last night of it disassembled. It looks filthy inside and the oil was THILCK! I tried cleaning with etoh, but will try acetone. I really need to know how much oil to put in there. I don’t trust measuring the nasty fluid that came out. My thoughts were to make sure that the heater in the bottom was covered and didn’t run dry, but open to suggestions!
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This is next on my list…
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