greenyppols - 11-12-2005 at 05:37
As I have well water and not willing to run a hydroaspirator for very long, that seems to leave me options of buying a pump with with teflon coatings
(expensive) or burning out an oil filled duo seal welsh pump Im thinking of acquiring, from acid vapor fumes that I read about in the vacuum threads
here and hadnt previously thought about..
I dont think that 5 gallon bucket idea with a pool pump is convenient either..for me at least..but is an option..
so I read about acid traps and cold traps for vacuum systems..thats expensive too..
I dont think a cold trap is needed if I can neutralize the vapors first..Im probably wrong but thats why I ask..
so I was wondering if anyone here has home made ideas to neutralize the acid vapors..I was thinking of wash-bottles of gallon size jugs or even a 6
gallon glass carboy filled with a solution with some PH paper floating around in it to judge when time to change....a calcium hydroxide solution
perhaps? I read in one the threads here too about dri-rite, but cant re-locate the thread and dont remember if it was used to neutralize acid vapor or
was intended as a moisture trap..or both?
Im not concerned too much about moisture though, as pump oil is cheap as compared to the cost of the pump and will change oil often anyway, or should
I be as equally concerned about moisture as the acid vapor?
BromicAcid - 11-12-2005 at 06:00
Wait, are you going to put wash bottles containing a solution of base between the vacuum pump and the apparatus being evacuated? Mind you under
vacuum water will boil at room temperature, I made that mistake once, setting up a gas wash bottle before my vaccum pump then turning it on, the
liquid in the wash bottle quickly started to boil and water was spraying out the other end of the pump. Usually they use solid KOH in line with the
vacuum pump and that's followed by a cold trap with liquid nitrogen, at least in my experience.
unionised - 11-12-2005 at 06:51
I doubt that many 6 gal, or even 1 gal, glass bottles are vacuum rated. I wouldn't want to be near one when somebdy checked.
A smaller container of solid KOH or quicklime would be a much better bet. You might want to trap some of the water out first with CaCl2 or some such.
greenyppols - 11-12-2005 at 07:07
Bromic....didnt think of that, but I should have. >slaps forehead<
unionised....so solid drying tubes of dri-rite and koh? Any idea how long the koh will last? Say...a 2 inch diameter glass tube, about 5 or 6 inches
long? Even a glass bubbler, perhaps? or maybe the koh first and then the dri rite? I have 3 three bubblers..so one can be left 'empty' to catch
anything in case of a shut off. Think that'll do it? Except the bubblers are not round and will probably implode, now that I think of it.
edit: anyone got pics of their setup? A pic is worth 1000 words. And google images doesnt seem to show much
[Edited on 11-12-2005 by greenyppols]