What's the best way to separate a dissolved mixture

  • Thread starter Thread starter Kombaiyashii
  • Start date Start date
  • Tags Tags
    Mixture
Click For Summary

Discussion Overview

The discussion revolves around methods for separating sodium bicarbonate from a dissolved solution in water, focusing on practical techniques for achieving a dry powder form. The scope includes experimental approaches and practical advice for home-based methods.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Experimental/applied

Main Points Raised

  • One participant describes their current method of evaporation using low heat in an oven but expresses difficulty in achieving complete dryness without crystallization issues.
  • Another participant suggests that maintaining a temperature below boiling and allowing the solution to simmer could be effective.
  • A different participant proposes using a dehydrator as an alternative method, highlighting its ease of use and ability to handle multiple solutions simultaneously.
  • Some participants recommend mixing or crushing the sodium bicarbonate during the drying process to enhance water escape.
  • There is a discussion about the use of a lid, with some arguing it may slow down the drying process by creating a saturated atmosphere, while others suggest a screen as a potential solution.

Areas of Agreement / Disagreement

Participants present multiple competing views on the best method for drying sodium bicarbonate, with no consensus reached on a single approach. Various techniques are proposed, each with its own considerations and potential drawbacks.

Contextual Notes

Participants note limitations regarding the effectiveness of different methods, such as the impact of temperature control and the presence of a lid or screen on the drying process. The discussion does not resolve these issues.

Kombaiyashii
Messages
5
Reaction score
0
Hi folks,

I like to recreate medival medicines from old manuscripts but I have come to a slight problem when it comes to the prepairation...

I'm trying to separate sodium bicarbonate which is dissolved in water. What I usually do is have a baking dish like the one below filled with the solution of water and sodium bicarbonate...I then put it in the oven on a low heat. After a while the water evaporates leaving mostly the sodium bicarbonate in the dish...

http://iweb.cooking.com/images/products/enlarge/183013e.jpg

The problems is that I can't get it very dry. I would like to evaporate all the water so I get a 100% powdered solution. If I carry on heating the solution, eventually the sodium bicarbonate crystalises which traps some water underneath and the crystals heat up and the whole thing starts spitting and then I get sodium bicarbonate all over my oven...


I was wondering if anyone knew a better way to separate the two and get a nice dry powder without too much work or expensive equipment?

Thanks,

Komb
 
Chemistry news on Phys.org
Seems to me your solution should work OK if you just keep the temp below boiling and let it simmer long enough.

Or you could just put a lid on the pan. Does it matter whether your precipitate is collected in the pan or on the underside of a lid?
 
@OP, do you have access to a dehydrator (usually used to dry fruits and vegetables)? Very little monitoring is necessary, and you can use the various trays to dry several solutions at once, if you like.
 
Many hours at temp below boiling, that's more or less the standard procedure.

Some mixing/crushing during drying won't hurt - you will break the surface and allow water to escape.

Lid will slow the process, you want the vapor to be able to leave the volume above the salt, as salt will be not drying under saturated atmosphere.
 
Borek said:
Lid will slow the process, you want the vapor to be able to leave the volume above the salt, as salt will be not drying under saturated atmosphere.
Right. A screen then.
 

Similar threads

Replies
1
Views
3K
  • · Replies 15 ·
Replies
15
Views
6K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
18
Views
7K
Replies
0
Views
2K
Replies
2
Views
2K
  • · Replies 13 ·
Replies
13
Views
14K
  • · Replies 2 ·
Replies
2
Views
4K
Replies
1
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K