Method for rapid detection of hexavalent chromium ions in sewage

Abstract

The invention specifically relates to a method for rapid detection of hexavalent chromium ions in sewage, which belongs to the field of detection of metal ions. The method comprises the following steps: adding 100 ml of distilled water or deionized water into a wash bottle; sequentially adding 1 ml of 1+1 sulfuric acid and 1 ml of 1+1 phosphoric acid and shaking up an obtained mixture; adding 4 ml of a prepared diphenylcarbazide solution and shaking up an obtained mixture; adding 100 ml of distilled water or deionized water and shaking up an obtained mixture for usage in subsequent detection; taking 2 to 5 ml of a water sample to be detected, adding 2 to 5 ml of a hexavalent chromium ion detection reagent with a wash bottle, shaking up an obtained mixture, observing the color of mixed liquor and determining the range of the content of chromium ions in detection liquid by observing whether the mixed liquor has a color or by observing the color which the mixed liquor displays. Application of the method provided in the invention for detection of hexavalent chromium ions enables detection time to be saved and on-site detection to be realizable; the method has the advantages of simpleness, easy operation and strong practicality.

Description

Technical field [0001] The invention belongs to the field of metal ion detection, and specifically relates to a method for rapidly detecting hexavalent chromium ions in sewage. Background technique In the detection process of sewage, it is usually detected whether the hexavalent chromium ion in the sewage exceeds the standard. The current general method for the detection of hexavalent chromium ion is the national standard method GB7467-87. This method can be used for quantitative detection. The time required for the method is about 30min to 60min. In the actual production process, only the hexavalent chromium ion in the sewage needs to be qualitatively tested when the on-site sewage is detected. The test results will be obtained in a short time, so the national standard method is not suitable for on-site qualitative testing. Especially for continuously operating sewage treatment plants, abnormal situations may occur at any time. Using national standard methods to monitor the...

AI Technical Summary

Problems solved by technology

In the process of sewage detection, it is usually detected whether the hexavalent chromium ion in the sewage exceeds the standard. At present, the general method for the detection of hexavalent chromium ion is the national standard method GB7467-87. This method can be quantitatively detected, but this The time required by the method is about 30min to 60min, but in the actual production process, only the hexavalent chromium ions in the sewage need to be qualitatively detected when testing the sewage on site, and often need to be detected in the field The test results will be obtained in a short time, so the national standard method is not suitable for on-site qualitative testing

Especially for continuously operating sewage treatment plants, abnormal situations may occur at any time

Using the national standard method to monitor the operation status of the sewage treatment plant, it is difficult to find abnormal conditions in time, because the national standard method generally takes 40 minutes from sampling, sample preparation, step-by-step dosing, static reaction, start-up detection, cleaning equipment, etc. If the operator is not familiar with the whole process, the detection time will be longer

In a long time interval, once an abnormality occurs, many water bodies will be polluted, and it will take at least 4 hours to reprocess and restore the operation of the device, which is a waste of manpower and material resources

In more than 4 hours, the sewage treatment device could not treat the sewage, and the polluted water had to be pumped back again, which increased the burden on the sewage treatment device

In addition, the national standard method requires instruments, and it is inconvenient for operators to bring instruments to the site for testing, which is also a major defect

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