METHOD FOR DETERMINATION OF POLYCARBOXYLIC ACID

摘要

PURPOSE:To make easy and exact analysis and to effectively suppress genera tion of scale by using a specific aq. soln. of a coloring agent diisobutylphen oxyethoxyethyldimethyl benzine ammonium chloride adjusted in pH. CONSTITUTION:The aq. 0.005-10W/V% soln. of the coloring agent diisobutyl phenoxyethoxyethyldimethyl benzine ammonium chloride is used after the pH thereof is adjusted to 10-13.5 by using a pH buffer agent. Measurement by an absorptivity measuring instrument is executed by imaging the light from a tungsten lamp W or deuterium lamp D2 as a light source to an incident slit S1 by a spherical mirror M1 and projecting the light further to a diffraction grating G by a spherical mirror M2. The light dispersed by the diffraction grating G passes an exist slit S2 and enters a sample. The light transmitted through the sample enters a detector. The intensity of the incident light is changed to an electric signal by the detector and is displayed as absorptivity, by which the concn. of the desired polycarboxylic acid is detected.