averageaussie
Hazard to Self
Posts: 85
Registered: 30-4-2023
Location: Right behind you
Member Is Offline
Mood: school 
|
|
?
|
|
|
chloric1
International Hazard
Posts: 1135
Registered: 8-10-2003
Location: GroupVII of the periodic table
Member Is Offline
Mood: Stoichiometrically Balanced
|
|
Could someone delete this thread? Something went awry
Fellow molecular manipulator
|
|
|
ThatChemist89
Harmless
Posts: 15
Registered: 14-8-2024
Member Is Offline
Mood: No Mood
|
|
sup
|
|
|
yobbo II
National Hazard
Posts: 757
Registered: 28-3-2016
Member Is Offline
Mood: No Mood
|
|
I think centrifuging is a much underused method of of seperating solids and liquids.
A guy here made one from and upturned bicycle.
Centrifuge and decant 
Yob
|
|
|
Rainwater
National Hazard
Posts: 913
Registered: 22-12-2021
Member Is Offline
Mood: indisposition to activity
|
|
I use a box fan layed on its back
"You can't do that" - challenge accepted
|
|
|
HydrogenFluoride
Harmless
Posts: 6
Registered: 26-8-2024
Location: Raleigh
Member Is Offline
Mood: Happy
|
|
I have not heard of that method before, but I quite like how it sounds. I bet that its performance will blow me away! I will have to test it out
sometime
|
|
|
chloric1
International Hazard
Posts: 1135
Registered: 8-10-2003
Location: GroupVII of the periodic table
Member Is Offline
Mood: Stoichiometrically Balanced
|
|
Centrifuging and vacuum filtration operation on the same principle. Pressure or force is applied to the precipitate to squeeze out the filtrate for
efficient separation. Vacuum filtration is more compact and more easily portable so it can be used in field work if need be
Fellow molecular manipulator
|
|
|
Boffis
International Hazard
Posts: 1863
Registered: 1-5-2011
Member Is Offline
Mood: No Mood
|
|
Of all my equipment that I have it is my vacuum filtration set-up that I use most often. I use a water ventury type vacuum pump and a range of Buchner
flasks from 100ml to 3 L with a set of ceramic Buchner funnels that take filter papers from 20mm to 150mm. I also have a selection of Hirsch funnels
and glass frit type funnels of various porosities and sizes.
They are so useful I just don't understand how anyone can do chemistry without such a set up. The sizes I use most frequently are the Buchner 4.25,
5,5 and 7cm size and the 2cm Hirsch funnel. If I were asked to recommend what equipment an amateur should buy first it would be a vacuum filtration
set up! Most other basic kit can be repurposed from domestic untensils until you start distillations etc.
|
|
|
Sulaiman
International Hazard
Posts: 3677
Registered: 8-2-2015
Location: 3rd rock from the sun
Member Is Offline
|
|
Quote: Originally posted by Boffis  | | Of all my equipment that I have it is my vacuum filtration set-up that I use most often...snip... so useful I just don't understand how anyone can do
chemistry without such a set up... |
I agree
A lot of people manage with just coffee filters or cotton wads, plus gravity,
but I like fine filtering,
and I'm too impatient to wait for gravity to do it's thing.
(except when I did some chemistry with gold I used mostly settling by gravity and decantation,
to minimise physical losses due to filtration,
so I suppose a centrifuge would be nice to have)
CAUTION : Hobby Chemist, not Professional or even Amateur
|
|
|
yobbo II
National Hazard
Posts: 757
Registered: 28-3-2016
Member Is Offline
Mood: No Mood
|
|
When filtering stuff like calcium sulphate where the ppt can be extremely fine, filtering can be very slow.
Centrifuging without a filter (just a container) and removing the liquid from the top of the solid can be useful.
Yob
|
|
|
chloric1
International Hazard
Posts: 1135
Registered: 8-10-2003
Location: GroupVII of the periodic table
Member Is Offline
Mood: Stoichiometrically Balanced
|
|
| Quote: Originally posted by yobbo II |
When filtering stuff like calcium sulphate where the ppt can be extremely fine, filtering can be very slow.
Centrifuging without a filter (just a container) and removing the liquid from the top of the solid can be useful.
Yob |
I am having an interesting experience with my current ammonium nitrate prep. About 98% of my calcium sulfate immediately precipitated with the
appearance of wet drywall sludge as expected. But as I go to boil down the clear ammonium nitrate filtrate, it will spontaneously go cloudy with the
dissolved calcium sulfate and I stop the stirring and heat to filter out what appears to be larger salt like crystals that are poorly soluble in
water. What’s more, you can filter this version of calcium sulfate through a regular coffee filter via gravity filtration. I expect a gram or two
of calcium sulfate each time I boil off 100 ml of water off the nitrate solution due to retrograde solubility.
I wonder if there is a way to grow nice gypsum crystals from ammonium nitrate solution?
Fellow molecular manipulator
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
