ASTM D4471-22 - Standard Test Method for Pyridine Bases in Cresylic Acid by Direct Titration
Standard Test Method for Pyridine Bases in Cresylic Acid by Direct Titration
|cresols; cresylic acids; nitrogen bases; phenol; pyridine bases; tar acids;
1.1 This test method covers the determination of pyridine and other basic nitrogen impurities in crude and refined cresylic acids streams, including mixtures.
1.2 This test method is applicable for pyridine base levels of 0.001 % to 0.5 %.
1.3 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice .
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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. For specific hazard statements, see Section .
1.6 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.