Diffusion pump ?

What is the purpose of a diffusion pump on a short path ?

purpose? deeper vac.

How does it function? I think thats been discussed here somewhere if you search diffusion pump, but if not maybe @spdking or @MagisterChemist can explain

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I’m curious why some people run a diffusion pump on a short path, I run one rotary vane pump and looking to add another pump, but hear about diffusion pumps

lol tryina start that war again?

I have a diffusion pump I still havent gotten set up yet, they seem to be very important for deep deep vac level stuff, I have had no issues distilling on my short path with a rotary vane however.


lol i guess i might as well tag @Kingofthekush420 while were at it


Curious does the diffusion pump come before or after the vacuum pump ? And is the diffusion pump hooked up to the vacuum pump ?

A diffusion pump is an addition to your vacuum array. so you would normally have your wet and dry pump in line with your short path,you then attach the diffusion after that array utilizing the cleanest driest vacuum path into the diffusion pump. The diffusion bumped then goes to a normal Edwards pump behind it to eject the molecules. you need a chillar to run the diffusion pump otherwise there are no moving parts It uses a vapor cloud or stream really two capture molecules between hot and cold surfaces


The purpose of a diffusion pump is to drop your vacuum down which increases your speed and gives you a better product while driving your temperature of your pot down. diffusion pumping sort of tricky and you can’t really cheap out because you got to have good oil good controllers good gauges and things that are going to give you accurate numbers so you know if you’re leaking or if you actually engaging in diffusion rates


It allows distillation to occur at a lower temp.


A nice diffusion pump can cost more than a short path kit.
You can run diffusion pump on wipe film, that make more sense cost wise.

That’s a very subjective statement. Using on a short path is just as effective if not more effective than a wiped film with diffusion, and that’s because short path develops more vapor pressure via the pot of fluid so you can jam more vapors down a diffusion pump that way and get incredible results and speed.

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So if I am using a SOGEVAC and a SUPERVAC, would I put the diffusion between the 2 vacs I’m currently using?

Direct vapor path hitting the SOGEVAC, then hitting diffusion, then pulling from diffusion with the SUPERVAC?

Imagine whatever you are doing as a whole. Nothing changes. Diffusion is like additional attachment on too of everything you have. It works on its own. You want it’s own roughing pump and use both your volatile and main pump as they are intended to be used.

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