Mixe - 19-6-2017 at 06:16
So I have this nice vacuum filtration funnel and flask, but the pump is still left to purchase. What kind of pump should one get? What suction should
it be able to produce? Naturally, I need it dirt cheap if possible.
I have a good grasp of electronics and mechanics, so if there's a salvageable option I'm all for it.
[Edited on 2017-6-19 by Mixe]
[Edited on 2017-6-19 by Mixe]
DFliyerz - 19-6-2017 at 06:23
I use this vacuum pump for filtration, which has worked very well for me over the years.
Sulaiman - 19-6-2017 at 06:41
The pump for vacuum filtration should not be too efficient or it may boil the filtrate 
and continuous pumping is not required, unless you have an air leak.
I use one of these http://www.ebay.co.uk/itm/DC-12V-Micro-Piston-Vacuum-Pump-80...
but any small vacuum pump should be good.
If you have running water available then a water aspirator vacuum pump would be good as it can also be used with 'nasty' fumes.
e.g. http://www.ebay.co.uk/itm/Aluminum-Alloy-Aspirator-Pump-Vacu...
Mixe - 19-6-2017 at 09:39
Really? That's all that's needed? I tried with a very similar 12V pump, but I didn't think it worked very well.
alking - 19-6-2017 at 09:50
I would suggest a water aspirator. If all you're ever going to do is filtrations then the 12V would be plenty, but a water aspirator is about the same
price, although you need a decent water pump to pair with it and a container to hold water unless you're going to use a faucet which wastes a lot of
water.
A water aspirator + rotary vane pump should be good for just about any vacuum needs you have and last awhile so long as you do not use the rotary vane
with any corrosive solvents. The water pump can vacuum solvents and fumes and the rotary vane can pull very deep vacuum for sublimations, vacuum
desiccations, etc. Oh, and you'll want to pickup a ball valve so you can control the rate at which you pull a vacuum as well as in order to close it
off after you've achieved it.