| 摘要 |
This invention embodies a process for synthesizing electrodialythically palladium ammine hydroxide for use in palladium plating baths. The electrodialys is takes place in a cell with a catholyte, a product and an anolyte compartments wh ich are divided by a fluorinated anion permselective membranes. Catholyte solution readily supplies OH ions, raw starting solution contains palladium ammine ions a nd anions capable of migrating into the anolyte compartment, and anolyte solution readily absorbs the anions from the raw solution. Electrodes, placed in the oute r compartments, are placed no more than 5 cm apart. The process is conducted with current densities of 500 ASF or less, with 200 ASF being preferable, with curren t efficiencies of 50 to 90 percent, with 60-80 percent being preferable, and at ba th temperatures of from above freezing to 40.degree.C, with 25-40.degree.C being pr eferable. The electrodialysis results in a stable palladium diammine hydroxide solution contai ning a small fraction of starting palladium diammine compound, such as palladium diammine chloride, making the final solution readily useable either as a repleni shing or a plating solution.
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