METHOD FOR REGENERATING A SOLUTION USED FOR PICKLING OR CHEMICALLY MILLING TITANIUM

摘要

The invention relates to a method of regenerating a spent titanium etching solution that is based on hydrofluoric acid and nitric acid and contains dissolved titanium. Said method involves determining the hydrofluoric acid and nitric acid concentrations in the solution, comparing each of the measured values with a respective associated predetermined threshold value, and adding KF and/or KNO3 to the solution when the respective HF and/or HNO3 concentration in the solution is below the associated threshold value. The method also includes determining the titanium concentration in the solution, comparing the measured value with a predetermined limit, and adding KF and KNO3 to the solution if the measured value exceeds said limit.