When equipping the Staff of Disintegration for the Kael’thas boss encounter in The Eye/Tempest Keep, the staff, which is 2H, will un-equip the weapons that currently have equipped. In my case, it was a druid with a 1H hammer and an offhand. The two weapons, instead of going into my inventory, were entirely destroyed, and not able to be restored. It may have been an edge case, like if my bags were full, and while equipping the 2H, my weapons had nowhere to go. In any case, there was no prompting that they would be destroyed - they were just entirely gone from my inventory. Since the items were not “sold”, there was no possibility of buying them back or recovering them.