GD-3200 Coulometric Water Analyzer for Karl Fischer Coulometric Titration
Which Karl Fisher Titration is adopted depends on the estimated water content in the sample:
Volumetric Karl Fischer Titration Iodine is added by a burette during titration, it is suitable for samples where water is present as a major component: 100 ppm - 100% Coulometric Karl Fischer Coulometric Karl Fischer Analysis Iodine is generated electrochemically during titration, it is suitable for samples where water is present in trace amounts: 1 ppm - 5%
Main Difference between Volumetric Karl Fisher Titration and Coulometric Karl Fisher Titrator:
1. In volumetry, moisture determination is made by taking into account the volume of reagent that is used in titration against moisture.
2. In coulometry, it is done by measuring current responsible for the generation of iodine.
3. The Coulometric Karl Fisher Titrator is used for assessing water content in petroleum and petrochemical products including oils, gasolines, solvents, and fluids as well as other products such as pharmaceuticals and cosmetics.
4. The Coulometric Karl Fischer titration is the ideal method to determine low moisture and water contents in samples (0.001 to 1% water content).
Electrolytic current |
400mA maximum |
Instrument resolution ratio |
0.1 ug |
Display |
7 inch high definition true color touch screen (1024*600) |
Printing |
wide line thermal printing |
Power supply |
AC220V±10% 50Hz±5% |
Environment temperature |
0 - 50ºC |
Volume AND Weight |
390×270×220mm ;6kg |
Environment humidity |
≤85% |
Karl Flscher reagent reacts with water below:
12 + SO2 + 3C5H5N + CH3OH + H2O = 2C5H5N·HI + C5H5N·HSO4CH3
The reagent solution used is prepared by mixing simple substance iodine, I- and SO2-containing methanol, etc. The measurement is based on the conductibility of the equilibrium system consisting of simple substance iodine andI-. The following reactions proceed alternately on two electrodes when the current is imposed on them:
2I--2e→I2
I2 + 2e→2I-
There is an excess of I- in the solution, but the I- concentration change does not greatly affect the solution conductibility. The change of simple substance iodine concentration within a range will cause an effective change of the solution conductibility. We select the range in which the higher simple substance iodine concentration leads to the bigger change of solution conductibility, and measure the value of the current intensity generated by the voltage at both ends of the platinum electrode immersed in the solution. The current intensity reflects the solution conductibility. A sample is injected to the electrolyte. The water in the sample reacts. The tester can detect the iodine change in the reaction, while the tester can calculate the iodine consumption from the electric quantity consumed when the same amount of iodine is electrolyzed out. The mass of the water to be tested is directly indicated on the LED display. This tester has an electrolytic current autocontrol system, which can automatically control the electrolytic current according to the water content of the sample. The maximum electrolytic current is up to 400 mA. During electrolysis, the water content gradually reduces, and the electrolysis rate reduced proportionally till an equilibrium point. The corresponding control loop of end point of titration starts, and the tester stops of measurement accumulation. This system ensures high analysis precision, sensitivity and speed. In addition, some interference factors unavoidably exist during measurement. For example, blank current is generated in the titration cell because of the water immersed in air. However, this tester has the memory and subtracts blank current, so the mass displayed on LED display is the real water content of the sample.
Service |
Device Problem Handling
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Social media 24 hours online communication |
Mail Seamless Docking |
Video Conferencing |
Packaging:
The Coulometric Water Analyzer are packaged with plastic box inside and carton box outside,1PC/Carton;
Delivery:
We will arrange delivery within 7 working days.
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If you are interested in our Coulometric Water Analyzer or have any questions, please feel free to contact us.