WATER IN PETROLEUM PRODUCTS AND LUBRICANTS BY COULOMETRIC KARL FISCHER TITRATION: ASTM D6304
TEST SUMMARY
This test method covers the direct determination of water in the range of 10 to 25000 mg/kg entrained water in petroleum products and hydrocarbons using automated instrument. This test method is applicable to additives, lube oils, base oils, automatic transmission fluids, hydrocarbon solvents, and other petroleum products. By proper choice of the sample size, this test method may be used for the determination of water from mg/kg to percent level concentrations. The normal chemical interferences in Karl Fischer titrations also apply to this test method.

The sample injection in the titration vessel can be done volumetrically or gravimetrically. The instrument automatically titrates the sample and displays the result at the end of the titration. Viscous samples can be analyzed by using a water vaporizer accessory that heats the sample in the evaporation chamber, and the vaporized water is carried into the Karl Fischer titration cell by a dry inert carrier gas.

TEST PRECISION

Where X is the mean of duplicate measurements. The values are in volume or mass percent.

This test method has no bias.