R&D Background: According to the national standard GB 11893-89, potassium persulfate is used to digest the sample under neutral conditions, and all the phosphorus contained is oxidized to orthophosphate; under acidic conditions, orthophosphate reacts with molybdate to generate phosphomolybdic heteropoly acid in the presence of antimony salt, which is immediately reduced by ascorbic acid to generate a blue complex, and the total phosphorus content is determined by spectrophotometry; at the same time, standard HJ636-2012 stipulates the determination of total nitrogen in water by alkaline potassium persulfate digestion ultraviolet spectrophotometry. The principle of the method is that at 120-124 degrees, alkaline potassium persulfate converts the nitrogen-containing compounds in the sample into nitrates, and the total nitrogen content can be determined by a UV-visible spectrophotometer. This instrument mainly refers to these two standards and realizes the automated determination of total phosphorus and total nitrogen.
Product technical advantages:
1. It can automatically perform batch sample digestion, cooling, volume setting, mixing, detection, colorimetric cell cleaning, data analysis and other operations throughout the entire process;
2. It can realize the semi-process automatic batch addition of oxidants, standard solution, and digestion steps; it can also automatically realize the operations of adding reagents, constant volume, mixing, testing, cleaning colorimetric cells, data analysis, etc. after semi-process digestion;
3. Realize the mixing mode imitating human hands to avoid pollution or loss caused by blowing or suction mixing mode;
4. Use a pipette-type reagent addition method to minimize cross-contamination of reagents between different experiments;
5. Use a high-precision syringe pump to add reagents to avoid the low precision problem caused by using a peristaltic pump;
6. Automatic opening and closing of the digestion bottle cover and automatic control of the digestion time;
7. Automatic drawing of standard curve and intelligent automatic proportional dilution;
8. The experiment was conducted in batches of 8, which improved the experimental efficiency compared with single experiments;