Chemiluminescence system and method for measuring dissolved oxygen

Abstract

The invention relates to a chemiluminescence system and a method for measuring the dissolved oxygen in water. The chemiluminescence system comprises solution A and solution B; the solution A is a luminescence reagent which contains 1.0 multiplying 10-4 to 1.0 multiplying 10 -3 mol / L of Luminol, 0.10-0.50 mol / L of CO32-, and 0.02-0.10 mol / L of HCO3-; the solution B is the liquid under test obtained after the treatment of water sample through dissolved oxygen fixing and free iodine steps in the measuring process with iodometry of dissolved oxygen. The main measuring steps are as follows: the blank solution, the standard solution and the test solution B are mixed and reacted with the solution A in a reaction detection container of a chemiluminescence apparatus, based on a volume ratio of 1 to 0.8-1.2, and the luminous intensity is detected so as to obtain the dissolved oxygen content in the corresponding sample. The invention combines the chemiluminescence with the iodometry so as to take advantages of high sensitivity and low detection limit of the chemiluminescence and avoid the problems of inaccurate endpoint determination, as well as complicated sodium thiosulfate configuration and calibration of the iodometry; besides, the invention has small reagent consumption, low cost, as well as accurate and reliable measurement result, and is suitable for the analysis and measurement of dissolved oxygen for most water bodies.

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