Uses for used vacuum pump oil!


#1

Hey everyone!

I was just thinking about how much pump oil I go through (20L+/mo) and got to wondering what else it’s good for/how to down cycle it.

I use the spent oil in vacuum pumps that I don’t need as deep of vacuum for, and it slowly evaporates from a couple of those.

I was Also thinking it might be a good heat bath oil! I have a jacketed still for evaporation, as well as using it for the jacket on a hot condenser for my short path. (I should check gasket/hose compatibility now that I think of it). It’s got quite a high boiling and flash point!

I hate waste! Anyone else have any good ideas for the stuff?


#2

Run it through a column and make it new again.
Water wash/steam bath works too.


#3

Will it hit as deep of vacuum? Is there a point of diminishing returns? Or can you water wash it indefinitely?


#4

Someone on here told me he uses it jn his old cummings diesel truck, i take mine to be recycled about 5 gallons+ a month.


#5

if you go on to distill it under vacuum then you’re getting closer to the process they use to manufacture it. if you use another oiled pump incorrectly to perform said distillation you’ll continue the cycle. utilize oxygen scavenging/sorption process media under super cooled conditions for reduced thermal breakdown to obtain better fractions of water white/pale oil suitable for “as new” use. there are industrial recycling companies that pickup.


#6

That stuff gets pretty smelly. I once ran a short path run on old vac pump oil. Under vacuum I pulled out the majority of volatiles and returned the oil to fairly fresh but hands down it was not worth the trouble. I just wanted to see how it went. None of the oil distilled over, just the stinky terps and such.

I normally have bbq briquettes on hand and often make a fire from them in my fireplace. I can pour the old oil on that a bit at a time and recycle the heat anyway. It burns well and steady and keeps the oil out of the ground water. Trying to salvage will likely cost more than new oil.


#7

I take my old pump oil and remove all the moisture with magnesium sulfate then load it into an aerosol can with butane.
Works good for a general lubricant in the garage.