Prinsip Metode Analisis Karl Fischer
Karl Fischer

Principles of the Karl Fischer Analysis Method

Created By: Hyprowira | Published Date: 02 August 2019 | Last Modified: 15 August 2019

Karl Fischer is a tool used by several industries. Karl Fischer is used as an alternative to moisture test. This tool itself uses the volumetric method based on the principle of titration. You also need to know that the Karl Fischer titration is an analytical method used to measure the water content in various products. The main principle is based on what is called the Bunsen Reaction between two things, iodine and sulfur dioxide which are contained in a medium that contains water.

How is Karl Fischer Used in Industry?

The industry's Karl Fischer titration is usually used to determine moisture content in raw materials. The determination of water content is carried out as part of a set quality test of raw materials.

An important note that you need to remember is, in the Karl Fischer titration of water only to be measured. It is different from the LOD (loss of drying) where all the substances evaporate including the water content and all the solvents. LOD itself is an analysis technique that is not specific, not only removes water but also all the volatile impurities, e.g. alcohol from the sample.

What do Karl Fischer Tools Consist of?

Karl Fischer is a three-part instrument, analytical scale (minimum 0.1 mg resolution), long syringe with small needle, and Karl Fischer reagent used as water content determination. To use Karl Fischer, you must place it on an area where the fluctuations in the temperature and humidity are awake. Why so? Because rising temperatures and humidity can interfere with the accuracy of moisture determination. Also keep the Karl Fischer tool from a tool that releases heat or cold.

Do you need a Karl Fischer Tool to Test Precision and Recovery?

As already mentioned earlier, Karl Fischer titration is a method of analysis that is used to measure water content in different products. Thus, calibration or qualification is required to guarantee the results of the resulting measurements.

Regarding this, there are differences of opinion about whether the Karl Fischer tool only needs to be calibrating or also needs qualification. Most of the parties argue that Karl Fischer includes the tools that need to be done qualifying because the tool includes complex tools and each part in it works together to perform measurements. Precision testing and measurement recovery is necessary to know the performance of Karl Fischer titration.

To perform precision tests and recovery, here's what you need to do:

-First, make sure the hose, container bottle and Burette are connected tightly.

-Then turn on the tools and printers.

-Fill solvent, stop filling until platinum indicator is unmerged.

-Weigh carefully 0.068-0.073 g DST (AT-Sodium Tartrate) standard with a Weighing Boat on analytical scales.

-Press the button to perform the analysis, wait until the value of Drift ≤ 25μg/ml or until the Sample Start button is visible or appears.

-Then press the Start Sample button, enter your weighed DST.

-Wait until it is finished, then the Karl Fischer tool will automatically print the result.

-When the result is out, note the result in the worksheet.

-To perform the precision test, do steps 4, 5, 6 and 7 as much as 6 times.

-After precision test, remove solvent, then clean Titration Beaker.

-To perform recovery test, run step 3-7 as much as 3 times.

That's the information about the principles of Karl Fischer analytical methods in the industry that matters to you. Hopefully useful!