| 摘要 |
Provided is a method for regenerating a nitric acid active treatment solution comprising: adding a zinc ion-aggregating agent to a nitric acid active treatment solution for a surface of a zinc-based material plated metal member, the nitric acid active treatment solution containing zinc ions, to thereby aggregate the zinc ions in the solution as an insoluble salt; and separating and removing the insoluble salt. This regeneration method is employed instead of methods conventionally and widely conducted in zinc-based plating on a steel material such as the exchange of the entire amount of the nitric acid active treatment solution after a lapse of a certain time, and is a method for regenerating a nitric acid active treatment solution, comprising: depositing and removing zinc ions which come to be mixed in the nitric acid active treatment solution during a zinc-based plating process on a steel material, so that the quality of a trivalent chromium chemical conversion treatment can be controlled at a constant level through simplification and cost reduction of a plating control step, and the waste nitric acid can be reduced as much as possible. |
