Patent ID: 8202431

Claim:
A method for removing impurities from a metal deposition process solution for deposition of nickel wherein the process solution is a nickel electrolyte containing organic decomposition products comprising: contacting the nickel electrolyte process solution containing the organic decomposition products with at least two distinct adsorbent media to remove the impurities from the process solution, wherein the adsorbent media are distinct from each other with respect to species of impurities adsorbed thereon, and wherein the method excludes any steps for oxidizing the solution prior to the step of contacting the solution with the adsorbent media; wherein the process solution is a nickel electrolyte containing organic decomposition products; and wherein the at least two adsorbent media comprise a first polymer resin for removing said organic decomposition products, which resin is selected from the group consisting of polyacrylate resin, polystyrene resin, polyacrylamide resin, and divinylbenzene/styrene copolymerisate resin and wherein during said contacting said organic decomposition products are adsorbed onto the first polymer resin, and a second polymer resin which is an ion exchange resin for removing from the process solution inorganic metal ion impurities selected from the group consisting of copper, chromium, iron, and combinations thereof; and wherein the first and second polymer resins are in separate polymer resin accommodation units; regenerating the first polymer resin and the second polymer resin independently of each other wherein regenerating the first polymer resin comprises: bypassing the nickel electrolyte process solution around the first polymer resin, and contacting the first polymer resin with an oxidizing agent to oxidize the organic decomposition products adsorbed thereon.