Working Principle of COD Analyzer

COD Analyzer is an important instrument for measuring chemical oxygen demand in water samples. It has a wide range of applications in environmental monitoring, water treatment and other fields. The following is a detailed introduction to the working principle of COD Analyzer.

The core principle of COD Analyzer is based on redox reaction. Strong oxidants, such as potassium dichromate, are usually used to oxidize organic matter in water samples.

The specific working process is as follows: First, a certain amount of water sample is added to the reaction vessel. Then, an appropriate amount of potassium dichromate solution and a catalyst, such as silver sulfate, are added. Under heating conditions, potassium dichromate undergoes a violent oxidation reaction with organic matter in the water sample.

During the oxidation process, organic matter is converted into substances such as carbon dioxide and water, while potassium dichromate is reduced to trivalent chromium ions. After the reaction is completed, the reacted solution is detected by colorimetry or electrochemical methods.

Colorimetry is the use of instruments such as spectrophotometers to measure the absorbance of a solution at a specific wavelength. The absorbance is related to the concentration of potassium dichromate or trivalent chromium ions remaining in the water sample, which indirectly reflects the COD value.

In order to ensure the accuracy and reliability of the measurement results, COD Analyzer is usually equipped with a series of calibration and quality control measures. For example, calibration with standard solutions, regular maintenance and inspection of the instrument, etc.

In short, COD Analyzer can accurately determine the chemical oxygen demand in water samples through specific chemical reactions and detection methods, providing important data support for environmental monitoring and water treatment.