The process of Co(II) and Ni(II) ions separation extracting from 3−4 M hydrochloric acid solutions by supported liquid membranes, containing tri-n-octylamine or trialkylbenzylammonium chloride in 1,2-dichloroethane, is studied during galvanostatic electrodialysis. The effects of the current density as well as of composition of the liquid membrane and aqueous solutions on the rate and selectivity of the cobalt(II) transport are determined. An effective separation of cobalt(II) from nickel(II) is achieved. Maximum separation factors of 147 (equimolar mixture), 330 (nickel(II) in excess) and more than 400 (cobalt(II) in excess) are obtained under optimum conditions.