4.1 The quantitative determination of acid-extractable content is useful in evaluating activated carbon samples that contain acid-soluble impurities. These acid-soluble impurities can affect applications of activated carbon.

4.2 Limitations of Method—Hydrochloric acid is used in this test method as the extracting acid. All elements or compounds present in the activated carbon sample, which can be acid extracted, are assumed to form water-soluble chloride salts. Hydrochloric acid may not solubilize all impurities of activated carbon.

1.1 This test method is to be used for determination of the acid-extractable content of a sample of activated carbon. This test method presupposes the existence of substances other than carbon to be present with activated carbon but does not purport to address or identify those substances which may be present. This test method should be applicable to any form in which activated carbon may exist and requires the performance of Test Method D2866.

1.2 This test method requires the use of concentrated hydrochloric acid, which should be used in an appropriate and safe manner, with eye protection, skin protection, and handling carried out in a properly operating fume hood. The proper use of a muffle furnace is addressed in Test Method D2866.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 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.

1.5 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.