The Question is How to remove ferrous oxide from Bleaching Earth (Bleaching Earth is also called Bentonite or Fullers earth)

Bleaching earth is primarily used in refining of edible oils (decolorizing and degumming) . Acid activation is used remove most of the oxides in the raw material , but the problem is with the Ferrous oxide, Usually oxalic acid is eased to remove ferrous oxide, but there are some government restrictions on usage of oxalic acid in edible oils. Just wanted to know if there is any other way to remove ferrous oxide.