concept Chemical Oxygen Demand (Chemical Oxygen Demand) refers to the amount of oxidant consumed in the treatment of water samples with potassium dichromate as the oxidant under strong acid and heating conditions, expressed as mg/L of oxygen. It reflects the degree of contamination of the water by reducing substances. principle Greater consumption = higher organic concentration Less consumption = lower organic concentration Sulfuric acid and potassium dichromate oxidation of organic matter is    2KC 8 H 3 O 4 + 10K 2 Cr 2 O 7 + 41H 2 SO 4 = 16CO2 + 46H2 O + 10Cr 2 (SO 4) 3 + 11K 2 SO 4 Instrument measurement method Instrument Measurement Principle (HJ/T399-2007) COD analyzer analysis flow chart For technical and commercial inquiries, please contact China InstrumentNet Manager (Hangzhou Yingou Instrument Co., Ltd.) Medical product moulds,Medical device moulds,Medical plastic product moulds,Medical product molds Medical Product Mold,Medical Product Molds,Medical Device Moulds,Medical Plastic Product Molds Dongguan Anding Technology Manufacturing Co., Ltd , https://www.cn-moulds.com
- Organics are oxidized, turning yellow hexavalent chromium into green trivalent chromium
- Cr6+ is yellow, Cr3+ is green, and the consumption of oxidant can be known by colorimetric method;
— Low range: 420nm, measuring the degree of yellow light intensity reduction High range: 610nm, measuring the degree of increase in green light intensity The degree of light intensity change is linear with the COD value; 