METHOD FOR PRODUCING MAGNETIC LIQUID Russian patent published in 2006 - IPC H01F1/28 

FIELD: magnetic liquid production; synthesizing main component of magnetic liquid iron phase (highly dispersed magnetite) from etching and electroplating process wastes.

SUBSTANCE: proposed method for producing magnetic liquid includes mixing of hydrochloric solution of electroplating process slug sediment and spent etching solution in Fe³⁺/Fe²⁺ = 3 : 2 proportion, production of magnetite slurry for which purpose mixture of solutions is peptized by adding 28% ammonium hydroxide and co-precipitation of bivalent and trivalent ferric oxides and their interaction, coating of magnetite particle surfaces in aqueous medium with adsorbing layer of stabilizing agent, heating of slurry of magnetic particles incorporating stabilizing agent layer adsorbed therein, their separation from water phase and mixing with other-than-water carrying liquid. Upon co-precipitation bivalent and trivalent iron slurry is exposed to 50-Hz variable magnetic field.

EFFECT: enhanced magnetic characteristics of magnetic liquid.

1 cl, 1 tbl, 5 ex