METHOD FOR MEASURING CONCENTRATION OF IMPURITY IN METAL ELECTROLYTE AND SYSTEM FOR REMOVING IMPURITY

摘要

PURPOSE:To make automatic measurement and high-sensitivity measurement by adopting a reverse flow injection method and properly selecting a buffer soln. CONSTITUTION:A 2M ammonium acetate soln., etc., are used as a buffer soln. and are supplied through a pump 2 and a pipeline 2a so as to be mixed with the sample soln. of a zinc sulfate soln. About 1% aq. soln. of a nitroso R salt is used as a Co color developing reagent. The addition of this reagent is executed by the reverse flow injection method which charges the reagent into the pipeline in which a sample liquid flows. The sample liquid added with this reagent is then introduced into a reaction coil 5 having a heater. Further, a mineral acid is added through the pump 3 and the pipeline 3a and the complex compd. formed by the reaction of the reagent and the metal exclusive of Co is decomposed by oxidation. A specified amt. of this sample reagent is introduced to a spectrophotometer 7 to measure absorption spectra. A previously determined concn. curve and the measured absorption spectra are contrasted and the concn. of the Co ions in the zinc sulfate soln. is determined. The automatic measurement and the high-sensitivity measurement are enabled by this measuring method.