What is Karl Fischer titrator?
Karl Fischer titration is a titration method that uses volumetric or coulometric titration to determine the quantity of water present in a given analyte.
Why Karl Fischer is used? Karl Fischer (KF) titration is a redox reaction which uses the consumption of water during the reaction to measure the amount of water in a sample. It is the reference method for water determination because of its specificity, accuracy and speed of measurement.
Karl Fischer (KF) Titration is a technique for the determination of moisture content. It is a process based on the reaction of iodine with water. The KF method is one of the few techniques that will measure water content and not be affected by other volatiles.
The principle of Karl Fischer titration is based on the oxidation reaction between iodine and sulphur dioxide. Water reacts with iodine and sulphur dioxide to form sulphur trioxide and hydrogen iodide. An endpoint is reached when all the water is consumed.
What is Coulometric titrator?
Coulometric titration is an absolute determination technique in which the mass of a given substance is determined by measuring the quantity of electricity required to electrolyze that substance。
What are the application of coulometric titration?
The Karl Fischer reaction uses a coulometric titration to determine the amount of water in a sample. It can determine concentrations of water on the order of milligrams per liter. It is used to find the amount of water in substances such as butter, sugar, cheese, paper, and petroleum.
How Does it Work?
The samples are placed in the rotating tray and sealed. Once the instrument starts, the first sample is moved into a temperature-controlled oven. Then, the sample is pierced so that as the water is converted into a vapor, it is transferred into either a coulometric or volumetric titrator which will determine the water content of the sample. By controlling the temperature, only the water evaporates while the remaining sample stays in the sample bottle. Once all of the water is removed and measured, the sample bottle is put back into its original position on the tray, and the tray rotates to the next sample to be performed.
Post time: Jul-04-2022