Process and apparatus for regeneration of chromium plating bath
AssigneeThe United States of America as represented by the Secretary of the Army
InventorsMark D. Miller, Joseph F. Cox, Steven Langston
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Abstract
A process for the regeneration of a plating bath comprising trivalent chromium involves the use of platinum anode and a copper cathode wherein the anode to cathode ratio is greater than 2:1 upon passage of a charge having a current density of at least 10 Amperes/diameter2 of exposed cathode. An apparatus for conducting the process is also disclosed. The described process obviates the need for an ion exchange resin and is conducted without the formation of any deleterious toxic sludge.
Claims14
Process for the regeneration of a plating bath including trivalent chromium cations, the process comprising a single plating tank forming a continuum fully containing the plating bath having disposed therein both a platinum containing anode and a cathode, the anode to cathode ratio being greater than 2:1, the process further comprises the steps of heating the plating bath to a temperature within the range of 80-85° C. and applying a charge having a current density of at least 10 A/dm2 of exposed cathode to plate chromium on the cathode while the anode in the plating bath oxidates the trivalent chromium cations to hexavalent chromium.
Apparatus for the regeneration of a plating bath containing trivalent chromium cations, the plating bath fully included in a single tank having disposed therein both a platinum anode and a copper cathode, the platinum anode oxidizes the trivalent chromium cations to hexavalent chromium while the copper cathode is plated with chromium in the plating bath of the single tank, the ratio of anode to cathode being greater than 2:1, means for heating said plating bath, and means for applying a current to said bath having a density of at least 10 A/dm2.
Dependencies are inferred from the claim text.