This is how I would do it:
- Weight 200g magnesium sulfate (Epson salts)
- Place it on an baking dish covered with Aluminum foil
- Heat it at 200 C for 2 hours
- Collect the anhydrous magnesium sulfate
- Store it in an air tight container for future use
- Fill a 500ml bottle with the solvent to be dehydrated (Acetone)
- Add 25g of anhydrous magnesium sulfate
- Shake and let settle for a day prior use
- Always keep the magnesium sulfate in the bottle
- For usage extract anhydrous Acetone from above with a pipette
- The magnesium sulfate should hold 2x its weight in water
- 25 g anhydrous magnesium sulfate holds 50 g water
- 50 g water is > 10% volume of 500ml Acetone
- When you get below 100ml, discard the Acetone
You could try to re-use the left over Acetone:
- Add it to 25g anhydrous magnesium sulfate and wait a day
- Decant the Acetone away from the the magnesium sulfate
- Add the Acetone with new Acetone (500ml total) to new magnesium sulfate (25g)
You can re-use the magnesium sulfate:
- re-heat in the oven for 2 hrs at 200 C
Good luck!
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