Sciencemadness Discussion Board

Hand-operated (manual) vacuum filtration apparatus

Gary - 12-11-2010 at 15:31

I have a hand-operated vacuum filtration apparatus, consisting of a Buchner flask, thick PVC tubing and a porcelain filter. This is fine for filtration purposes, but could the apparatus be adapted to provide a vacuum for hastening the removal of solvents by evaporation?
I personally doubt that the vacuum afforded by these manual pumps is far below atmospheric pressure.

BlazeBall - 12-11-2010 at 18:30

Manual vacuum pumps can manage -30 inches of Hg.

Justin - 12-11-2010 at 20:58

You could, but you'd be pumping away for hours and probably have carpal tunnel when you were done! You have to remember your sucking the solvent vapors thru the pump which will attack the seals and plastic. You'd be much better off with a aspirator, i think i have an extra nalgene aspirator

metalresearcher - 17-11-2010 at 02:04

I am also looking for a simple hand operated vacuum pump and on ebay there are several devices some even wiith a gauge with affordable prices.

But how deep can the vacuum be ? 0.5 bar or even 0.1 bar (== 0.9 bar underpressure) ?

Phosphor-ing - 17-11-2010 at 06:44

I bought one of those vacuum pumps with a gauge on it from my local auto parts store. Can't remember what it cost. But it was for bleeding brake lines on a car. Harbor Freight also carries a version with a gauge for about $25.

http://www.harborfreight.com/brake-bleeder-and-vacuum-pump-k...


digitalemu - 18-11-2010 at 12:11

Buy an aspirator, they are great for what you need to do. A brake bleeder will cost you much more and not last as solvents will eat away at the rubber seals and gaskets. An aspirator will basically last forever with zero maintenance.

http://cgi.ebay.com/CHAPMAN-VACUUM-HYDRO-ASPIRATOR-FILTER-PU...

Also buy this adapter and you can hook this up directly to a laundry tub faucet.
http://cgi.ebay.com/FAUCET-ADAPTER-VACUUM-HYDRO-ASPIRATOR-/3...