【国外标准】 Standard Test Method for Water in Organic Liquids by Coulometric Karl Fischer Titration

4.1 The coulometric technique is especially suited for determining low concentrations of water in organic liquids that would yield small titers by the Karl Fischer volumetric procedure. The precision and accuracy of the coulometric technique decreases for concentrations of water much greater than 2.0 % because of the difficulty in measuring the small size of sample required. The test method assumes 100 % efficiency of coulombs in iodine production. Provision is made for verifying this efficiency. (See Table 1 and Note 5.)1.1 This test method covers the determination of water from 0 % to 2.0 % mass in most liquid organic chemicals, with Karl Fischer reagent, using an automated coulometric titration procedure. Use of this test method is not applicable for liquefied gas products such as Liquid Petroleum Gas (LPG), Butane, Propane, Liquid Natural Gas (LNG), etc.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 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first-aid procedures, handling, and safety precautions.1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.1.5 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.