Just did a search on Magnesium Sulfate in the nexus and could not find comprehensive information. So I thought I'd post MgSO4 regeneration. Maybe this is helpful to someone.

Ah, yes... there is actually a Wiki entry for epsom salts: Rendering Anhydrous Magnesium Sulfate Well, maybe the link is still useful.

microwave radiation effectively dehydrates epsom salt, because commercial microwaves are specifically tuned to excite the dipole forces in water molecules. 5-10 mins on high power usually dries magnesium sulfate completely.

It works very well, but the large rock in my beaker can be a pita to work with.

First time I actually regret not having a microwave. But worked just fine in the oven. Just took an hour longer. I was a bit surprised by the salt becoming a single big rock ^^ Also, it was not necessary in the end, since my acetone turned out to be very anhydrous