ASTM C1733-21

4.1?The distribution coefficient, K_d, is an experimentally determined ratio quantifying the distribution of a chemical species between a given fluid and solid material sample under certain conditions, including the attainment of constant aqueous concentrations of the species of interest. The K_d concept is used in mass transport modeling, for example, to assess the degree to which the movement of a species will be delayed by interactions with the local geomedium as the solution migrates through the geosphere under a given set of underground geochemical conditions (pH, temperature, ionic strength, etc.). The retardation factor (4.2?Because of the sensitivity of K_d to site specific conditions and materials, the use of literature derived K_d values is strongly discouraged. For applications other than transport modeling, batch 1.1?This test method covers the determination of distribution coefficients, 1.2?The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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

1.4?This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.