Water is an unwanted constituent of all kinds of gases. Precise determination is therefore a must, e. g., in medical gases, noble gases, process gases, and welding gases. The 875 KF Gas Analyzer is a highly robust solution for this kind of analysis, combining precise sampling with the accuracy of coulometric Karl Fischer titration in a fully integrated, software-controlled analyzer.
Water can be determined with various analytical techniques at trace levels. However, water in gases is a particular challenge: Most of the feasible methods need to be calibrated and can only determine the water content indirectly. In contrast, Karl Fischer titration measures the absolute amount of water in the gaseous matrix. Moreover, results do not tend to drift, as the reagent is exchanged at regular intervals. As Karl Fischer titration is a primary method, the sensor does not need to be calibrated either. Detection limits of the method lie in the single-digit ppm range (µg water/g gas).