Cou
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What apparatus is used for bubbling gasses through liquids?
Such as bubbling HCL through water to make hydrchloric acid, or nitrous oxide through a sodium hydroxide solution to remove the toxic NO2. How do you
do this, or is there an apparatus?
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Zyklon-A
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No special equipment needed, lead the gas through a tube from you reaction flask, into the solution that is scrubbing out your gas.
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bfesser
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Thread Moved
26-2-2014 at 16:38 |
Mailinmypocket
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There are things called dreschel bottles made specifically for this purpose. There are also gas dispersion tubes with sintered glass frit at the end
for making fine bubbles through a solution. The original response is the cheapest option though, obviously
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ZIGZIGLAR
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Not that dreschel bottles are expensive. Even sintered glass filtered ones can be had for $20 if you look around. You'll sometimes find these under
"gas trap", "gas wash bottle" or "bubbler".
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S.C. Wack
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For many things one does not bubble through at all until maybe already highly concentrated from mere surface contact.
On the larger scale, fritted glass funnels and Soxhlet thimbles are great. I have a fancy gas dispersion thingy that's a glorified thimble.
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MrHomeScientist
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One does not simply bubble through Mordor!
Something to also consider is suck-back. If gas production slows, temperature changes, or if your gas is highly soluble, fluid can be sucked back
through the tube and into your reaction flask. You need to have an empty flask in between your gas generator and water bubbler to safeguard in case
this happens. An easy way to prevent suck-back is the "inverted funnel trick" - instead of having a tube immersed in your bubbling flask, attach the
tube to the stem of a funnel and suspend it so the rim of the funnel hangs a little below the surface of the water. If suck-back starts to occur, the
water level will lower enough to break the seal on the funnel and equalize the pressure. Not the most efficient gas bubbler, but it works great for
very soluble gases like ammonia.
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macckone
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Quote: Originally posted by MrHomeScientist  |
One does not simply bubble through Mordor!
Something to also consider is suck-back. If gas production slows, temperature changes, or if your gas is highly soluble, fluid can be sucked back
through the tube and into your reaction flask. You need to have an empty flask in between your gas generator and water bubbler to safeguard in case
this happens. An easy way to prevent suck-back is the "inverted funnel trick" - instead of having a tube immersed in your bubbling flask, attach the
tube to the stem of a funnel and suspend it so the rim of the funnel hangs a little below the surface of the water. If suck-back starts to occur, the
water level will lower enough to break the seal on the funnel and equalize the pressure. Not the most efficient gas bubbler, but it works great for
very soluble gases like ammonia. |
Another solution is a suck-back trap. This is basically a pass through
bottle for the gas with the inlet tube at the top and the outlet to the
bubbler extended to the bottom. For chlorine generation you probably
want an overflow trap as well which has the inlet tube at the bottom
and the outflow tube at the top. Calcium Chloride tubes (U-tubes) are
useful for this as well although they don't allow the correct flowback
from the trap if conditions change.
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forgottenpassword
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Use a non return valve.
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