Method for online automatic detection of permanganate index in water

Abstract

The invention discloses a method for online automatic detection of permanganate index in water. The method comprises the following steps: preparing a used reagent; finishing calibration of a standardcurve, and verifying the accuracy and repeatability of online automatic detection equipment and glucose test; manually testing different types of surface water and standard solutions thereof in a laboratory according to a national standard method to obtain permanganate indexes in the surface water; testing the corresponding surface water and the standard solution thereof by online automatic detection equipment to obtain absorbance; enabling the online automatic detection equipment to calculate permanganate indexes in different types of surface water according to the standard curve; and comparing a laboratory method with an automatic calculation method, calculating a relative error, and judging whether the relative error is within a standard requirement range. By using the method provided by the invention, the accuracy and repeatability of the online automatic detection equipment are good, the glucose test and the adding standard recovery rate meet the requirements, and the method has great significance for environmental protection in the field of online monitoring of surface water quality.

Description

technical field [0001] The invention relates to the field of analytical chemistry and detection, in particular to an online automatic detection method for permanganate index in water. Background technique [0002] The laboratory measures the permanganate index in water according to the national standard: "GB 11892-89 Determination of Permanganate Index in Water Quality", specifically: use a pipette to accurately pipette 100.0ml of distilled water or shake and mix thoroughly Put a uniform sample in a 250ml Erlenmeyer flask, add 5±0.5ml of dilute sulfuric acid solution with a concentration of 25%, add 10.00ml of potassium permanganate solution with a concentration of 0.01mol / L with a burette, shake well, and put the conical Place the flask in a boiling water bath for 30±2min. After heating, take out the Erlenmeyer flask and add 10.00ml of sodium oxalate solution with a concentration of 0.01mol / L with a burette until the solution in the Erlenmeyer flask becomes colorless. Titr...

AI Technical Summary

Problems solved by technology

This method requires more reagents and produces more waste liquid; at the same time, because the on-site water samples need to be taken back to the laboratory, and then manually tested, the effectiveness of the data is not high; the most important thing is to pipette When measuring water samples and corresponding reagents, the titration process is greatly affected by human factors, resulting in poor accuracy and repeatability of test results

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