Keras
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Makeshift (slight) vacuum generator
Folks,
if you couldn't use a water aspirator or a vacuum pump, what makeshift contraption would you use to create a vacuum suitable to drive a vacuum
filtration?
I was thinking about pouring water in a vanilla plastic box into which the vacuum tubing is inserted. You put the box in the microwave oven, make the
water boil, then you seal the box with its lid. As the water cools, a depression forms in the box, that could be used to suck the air out of the
filtering erlenmeyer.
Other propositions?
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Rainwater
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They sell these little hand pumps for filtering.....
https://www.homesciencetools.com/product/hand-operated-vacuu...
"You can't do that" - challenge accepted
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Keras
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Yes, I had already seen those hand pumps. But do they really work and keep working after the first week of use? They say best-seller, but I’m not
sure I actually ever met someone who had used one of them!
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Sulaiman
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For vacuum filtration :
https://www.amazon.com/gp/aw/d/B07H4R7QNC/ref=sspa_mw_detail...
or similar
For vacuum distillation. :
https://www.amazon.com/gp/aw/d/B08P1XD311/ref=sspa_mw_detail...
or similar
PS both types of vacuum pump have noisy output ports so I pipe the exhaust outside or far from the working area.
[Edited on 17-5-2023 by Sulaiman]
CAUTION : Hobby Chemist, not Professional or even Amateur
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paulll
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Mood: It's fine. Really.
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Quote: Originally posted by Keras  |
Yes, I had already seen those hand pumps. But do they really work and keep working after the first week of use? They say best-seller, but I’m not
sure I actually ever met someone who had used one of them!
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Mine's been in use for a couple of years, works well.
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Rainwater
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Missed that on my first read.
Reverse it, apply high pressure to the filter, instead of vacuum.
Use this method to recycle my vacuum pump oil after removing the water with anhydrous MgSO4. Works like a champ until you have a leak and
blow hot oil across the room in a jet that can cut sheet rock
"You can't do that" - challenge accepted
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B(a)P
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Quote: Originally posted by paulll  | Quote: Originally posted by Keras  |
Yes, I had already seen those hand pumps. But do they really work and keep working after the first week of use? They say best-seller, but I’m not
sure I actually ever met someone who had used one of them!
|
Mine's been in use for a couple of years, works well. |
We used to use these for vacuum filtration in the field, the metal bodied ones like this last for years.
The plastic cheaper ones as linked above were found to be variable in how long they lasted and were generally not as efficient.
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Lionel Spanner
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I use a pump very much like the second for both applications; it cost me £70. It easily and routinely draws a vacuum around 0.05 - 0.10 bar, and
could probably go lower if I put a sufficiently cold trap in the line.
Industrial chemist rediscovering the practical pleasures of pure chemistry.
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