I noticed this myself, but I moved all the items it tried to salvage into my invisible bags for safety.
Did eventually try to salvage them, but turns out that you indeed can't do it.
The items include Mortar Seed Turret, Ogre Pet Whistle, Tuning Icicles, and Fire Elemental Powder.
Edit: Also Lumps of Crystallized Nougat, Flasks of Pumpkin Oil, and Sharpening Skulls.