How to Make Anhydrous


Anhydrous is a state of a chemical indicating that it is free of water. The exact drying procedures vary from chemical to chemical, though most powdered salts can be produced using this procedure.

Things You'll Need

  • Salt to be dried
  • Heating mantel
  • Round bottom flask
  • 3-way valved adapter for flask (2 of the 3 should be hose connections)
  • Keck clip
  • High vacuum line
  • Pure nitrogen line
  • Place the salt (aqueous or solid) into the round bottom flask.

  • Place the round bottom flask in the heating mantel.

  • If the salt is aqueous, gently heat the solution until steam occurs and then keep at a constant temperature until nearly all of the water has evaporated.

  • Connect the 3-way valved adapter to the top of the round bottom flask using a Keck clip. Connect the vacuum line to one hose port and the nitrogen line to the other.

  • Open the valve to the vacuum line, reducing the pressure inside of the round bottom flask.

  • Heat for another 20 minutes with the vacuum line open.

  • Turn the valve so that the round bottom flask is filled with nitrogen.

  • Repeat Steps 5-7 three times then remove the flask from heat.

  • Close off the valve. This will trap the dry salt inside and prevent it from absorbing moisture from the air.

Tips & Warnings

  • A hot plate with a silicon oil bath can be substituted for the hot plate. Some salts may require additional heating/ vacuuming to remove water.
  • A hot plate can easily cause burns. Silicon oil boils over the boiling point of water; therefore any water in the oil will make the oil splatter, easily causing burns.

Related Searches


Promoted By Zergnet


You May Also Like

  • How to Make Seasoned Salt

    Watch out if you decide to dip your toe into the world of making your own seasoning salt. You may start with...

  • How to Remove Ammonia From Salt Water

    New saltwater fish hobbyists and veteran hobbyists alike are vexed by the problem of how to safely remove ammonia from their salt...

  • How to Make Sodium Citrate Anticoagulant

    Sodium citrate is a salt produced through the reaction of sodium carbonate with citric acid that serves as an anticoagulant for fractionated...

  • How to Make Salt Dough

    Salt dough is a fun, easy-to-make recipe that can be formed, molded, cut and dried to make all sorts of figures. Use...

Related Searches

Check It Out

How to Make a Vertical Clay Pot Garden

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!