Wide Measuring Range Volumetric Karl Fischer Moisture Tester

Wide Measuring Range Volumetric Karl Fischer Moisture Tester

Introduction

AKF-V1 is a volumetric method Karl Fischer Titrator. The instrument has been designed with the latest mechanical and electronic technology and a user-friendly interface. It is reliable, accurate and has a wide measuring range (0.001%-100%). It is also economical and practical, and can be used for accurate analysis of solid, liquid and gas samples. It can be used for the analysis of crystal water, adsorptive water and free water. It is suitable for use in a number of industries, including petroleum, chemical, pharmaceutical, daily chemical, food, agriculture, laboratory and many other sectors.

Principle

The Karl Fischer moisture determination method is a non-aqueous REDOX titration method. The fundamental principle of the titration is that iodine oxidation of sulfur dioxide necessitates a specific quantity of water to participate in the reaction. The chemical reaction equation is as follows:

The chemical reaction equation is as follows:

I2 + SO2 + 2H2O → 2HI + H2SO4 (2-1)

I2 + SO2+ H2O + 3RN + CH3OH → 2RNHI + RNSO4CH3 (2-2)

The Karl Fischer reagent contains The reagent is a dark brown solution of molecular iodine. When the reagent or a sample containing water is added, a chemical reaction generates the methyl sulfate complex (RNSO4CH3), which turns the solution yellow. This change in color can be visually assessed, ranging from light yellow to orange. However, the visual method is not sufficiently accurate and can lead to errors in the determination of coloured substances. The majority of national standards require the use of the 'permanent stop method' to determine the end point of the reaction. This is achieved by inserting double platinum electrodes into the reaction solution and applying a fixed voltage between them. If water is present in the solvent, an electric pair will not form in the solution, resulting in a non-conductive solution. At the endpoint of the reaction, an I2 and I- electric pair will be present in the solution. This results in a sudden increase in solution conductivity, as well as a corresponding increase in current between the two platinum electrodes. The current stabilises at a value set in advance, which allows the end of the titration to be determined. The machine then stops the titration, allowing the water content of the sample to be calculated based on the volume of KF testing agent consumed.

Technical Features:

1. A constant voltage is applied to the double platinum electrodes, and the titration end point is indicated by collecting the current signal.
2. Fully closed system, titration cup, solvent bottle, reagent bottle are equipped with drying tube to avoid the infiltration of environmental moisture.
3. Push-button operation instrument can be realized: metering tube cleaning, quantitative feed, solvent absorption, waste liquid discharge, automatic titration.
4. The status light indicates whether the instrument is working and ready, the
titration curve is dynamically displayed, and the calibration, sample
measurement and verification results are automatically saved.
5. When idle, the environmental water drift will be automatically tracked, and the
drift deduction will be selected when calculating the results to ensure the
accuracy of the analysis results.
6. It can automatically replace fresh solvents, reagents and discharge waste liquid, closed structure can reduce volatile gas escape of reagents and solvents.
7. During the titration process, the titration speed is automatically adjusted
according to the water content in the titration cup, and the titration volume, titration speed and electrode signal are displayed in real time.
8. With user rights management, support English and Chinese language switching.
9. Running smoothly and has low noise.

Technical Specification