raney nickel

[Entropia]

What *is* raney nickel? And, what different kinds of "raney nickel" are there?

[Bystander]

Raney Ni is "finely divided" Ni, prepared not by grinding to a fine powder (entirely too coarse, and oxidized), but chemically by dissolving more active metals from Ni containing alloys --- leaves just the Ni, lots of surface area with a definite physical and chemical history for catalytic purposes. There may also be electrolytic methods, analogous to platinization, but I'm not aware of any common ones.