ASTM D890-98

1.1 This test method covers the quantitative determination of dissolved or occluded water present in any proportion in light-colored, liquid naval stores, such as turpentine, pinene, dipentene, pine oil, refined tall oil, and tall oil fatty acids. It is based on the reaction between water and a complex reagent consisting of iodine, sulfur dioxide, pyridine, and methanol, whereby the iodine is converted to a colorless compound. The appearance of a persistent iodine color in the reaction mixture indicates the complete removal of free water by reaction with the reagent.

Note 1-The Karl Fischer reagent prescribed in this test method is prepared in two solutions, in which form it is more stable and less affected by atmospheric moisture. However, the single solution reagent described in Test Methods D1364 and Method D1123 may be used if it is more readily available. The solvents and proportions specified in this test method should be employed if the single solution reagent is used.

1.2 For dark-colored liquid naval stores products such as crude tall oil, an alternate method described in Test Methods D803 is recommended.

1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.>