You can dry in oven at 100-110 C for 3-5 hours .You may use desiccator to keep it dry  and anhydrous under vacuum for longer hours.Hope this helps.

You can dry in oven at 100-110 C for 3-5 hours .You may use desiccator to keep it dry  and anhydrous under vacuum for longer hours.Hope this helps.

Dear Fatma Allam ,

I think by heating at elevated temperature will remove water of hydration that will deform the crystal structure of the compound.

to avoid the moisture you must store it in Silica gel Desiccator and if necessary to dry by heating then use only 50 C drying temperature.

Also you can use vaccum and chilling for the purpose to avoid moisture as well.

Regards.

Dear Muhammad Imran,

Thanks for your answer. Actually I can dry it in 50 C, is that suffecient? Also I would like to ask you about this method that you mentioned, vacuum and chilling, is there any publication explaining it?

You cna dry it this way up ro a certain point and it will be useful only for certin purposes. Too much heat will transform your compound into something like ClMg(OH) which will contaminate your MgCl2. In this case, your salt will not be useful for certain applications.

Good luck!

Hello Fatima,

At 50 C atmospheric pressure  you won't be able to remove water completely, unless your are using vacuum (vacuum drying). You may refer to USP monogram for drying condition of MgCl2.6H20.

yes, you can dry it at 50 C under vacuum to remove H2O. Then, keep it in desiccator for long life

Dear Fatma! If you want to remove crystal water, it is heated in the oven can be up to 125-130 deg.

Luck!

Those interested at this RG discussion may possibly want to check my post elsewhere at this forum; addressing the effect of air humidity on magnesium chloride (MgCl2) or its hydrates: https://www.researchgate.net/post/weight_equivalence_chemistry