Nutrient salt online analyzer

Under alkaline medium conditions, potassium persulfate is used as an oxidant to oxidize ammonia nitrogen and nitrite nitrogen in the sample into nitrates, and most of the organic nitrogen compounds in the sample are oxidized into nitrates. NO3- reacts with resorcinol in an acidic environment. Within a certain concentration range, the color depth is proportional to its concentration. The absorbance is measured at a wavelength of 375nm and converted into a total nitrogen concentration value after correction by the calibration curve.

In the presence of potassium persulfate, the nitrogen-containing compounds in the water sample are completely converted into nitrate nitrogen after high digestion. The absorbance of the complex is measured by a spectrophotometer at a wavelength of 220nm and converted into a total nitrogen value.

After the water sample and the masking agent are mixed, ammonia nitrogen in the form of free ammonia or ammonium ions reacts with the salicylic acid colorimetric reagent in an alkaline environment and in the presence of a sensitizer to form a colored complex. The absorbance of the complex is measured by a spectrophotometer to calculate the concentration of ammonia nitrogen in the water sample.

Ammonia nitrogen in the form of free ammonia or ammonium ions reacts with Nessler's reagent to form a light reddish-brown complex. The absorbance of the complex is measured by a spectrophotometer to calculate the concentration of ammonia nitrogen in the water sample.

The mixture of water sample, catalyst solution and strong oxidant digestion solution is heated to 120°C. Polyphosphate and other phosphorus-containing compounds in the water sample are digested and oxidized by strong oxidants under acidic conditions of high temperature and pressure to generate phosphate. In the presence of a catalyst, the phosphate ions generate a colored complex in a strong acid solution containing molybdate. The absorbance of the complex is measured by a spectrophotometer to calculate the concentration of total phosphorus.

This product uses the resorcinol spectrophotometric method to determine nitrate nitrogen. Resorcinol reacts with nitrate nitrogen to generate a colored compound, and the absorbance of the compound is measured by a spectrophotometer to calculate the concentration of nitrate nitrogen.

This product uses N-1-naphthylethylenediamine spectrophotometry to determine nitrite nitrogen. In an acidic solution, nitrite ions undergo a diazotization reaction with sulfonamide, and then couple with N-(1-naphthyl)-ethylenediamine to generate a purple-red dye. By measuring the absorbance of the dye at a specific wavelength (such as 540nm), the content of nitrite can be quantitatively analyzed.