Measuring moisture contamination in alternative fuel

By Control Engineering Staff September 21, 2006

The Aquacounter titrator from Karl Fischer is compact and allows technicians to measure moisture content quickly and easily.

The growth of alternative fuels research and use has spurred the need for a simple and reliable method for measuring moisture content to avoid operational problems in engines and turbines. Alternative fuels, such as ethanol, methanol, natural gas, propane, biodiesel, etc., are becoming more common, but some of them have handling characteristics different from typical gasoline and diesel fuel. Ethanol is very hygroscopic and tends to absorb airborne moisture. Water in biodiesel feeds bacterial contamination.

Preventing moisture-caused problems such as plugged fuel filters, reduced lubricity, and freezing requires moisture analysis close to the point of use. A new coulometric titrating device from Karl Fischer reportedly makes this process fast, simple, and highly reliable. A measured sample of the fuel is placed in the machine and a reagent containing iodine is added. The iodine reacts with the water in the sample, and the water is quantified on the basis of the total charge as measured by current and time. Depending on the moisture content, the sample required varies from 0.5 to 5 grams.

The Aquacounter AQ-300 coulometric Karl Fischer titrator is reportedly designed to perform such analysis quickly, easily, and with small sample sizes of liquid, solid, and gas products. A training DVD assists users through the process of performing tests using one of six built-in calculation modes. The unit accumulates data for up to 20 tests and can perform simple statistical functions or download data into another computer. Titration status is continuously monitored and direct key access allows entry of titration parameters.

Control Engineering Daily News Desk

Peter Welander , process industries editor