Do you know how many measurement principles the water quality multi-parameter detector has?

The water quality multi-parameter detector adopts imported high-brightness LED cold light source and advanced German optical structure, with good optical performance and detection effect; user-friendly operation interface. Simple measurement methods and large-screen LCD display make professional and Non-professional personnel are handy to use. It is a right-hand man for scientific research, data analysis, and water quality testing. It is widely used in scientific research institutes, sewage treatment, environmental monitoring, petrochemicals, papermaking, pharmaceuticals, printing and dyeing, textiles, leather, winemaking, and electronics. The municipal administration. Universities and other industries have received unanimous praise from users.

This instrument is based on the principle of the characteristic absorption spectrum and light absorption law (Lambert-Beer law) produced by the substance molecule to visible light, and it uses the method of comparing the unknown concentration sample with the known concentration standard substance for quantitative analysis.

The instrument is composed of the LED light source, colorimetric cell, photoelectric sensor, microprocessor, and micro-printer, which can directly display the content of certain items or certain pollutants in the tested sample on the LCD screen, and print out the analysis results.

Measurement principle:

COD measurement principle (chromium method): in the presence of excessive potassium dichromate in a strong acid solution, silver sulfate is used as a catalyst, and the reducing substances in the water are catalyzed by heating to oxidize the reducing substances in the water through hexavalent chromium or trivalent chromium The relationship established between the absorbance value and the COD value of the water sample is used to determine the COD value of the water sample.

Principle of ammonia nitrogen determination (Nessler's reagent method): Ammonia nitrogen in the form of free ammonia or ammonium ions reacts with Nessler's reagent to form a reddish-brown complex, which is proportional to the content of ammonia nitrogen according to the absorbance of the complex. To determine the ammonia nitrogen content in the water sample.

Principle of total phosphorus determination (ammonium molybdate method): After the sample is digested, all the phosphorus contained in it is oxidized to orthophosphate. In an acidic medium, orthophosphate reacts with ammonium molybdate to form phosphomolybdic in the presence of antimony salt, which is immediately reduced by ascorbic acid to form a blue complex. The total phosphorus content in the water sample is determined according to the absorbance of the complex.

Principle of total nitrogen determination (thymol method): Add alkaline potassium persulfate solution to the water sample, under high temperature and high pressure, the nitrogen element of the nitrogen compound in the water sample can be converted into nitrate, which can make the water The nitrogen element of the nitrogen-containing compound in the sample is converted into nitrate, which forms a nitrophenol compound with thymol in a solution of concentrated sulfuric acid, and molecular rearrangement occurs in the alkaline solution to form a yellow compound.