1.1 本试验方法通过滴定法定量测定纯化甘油中的脂肪酸和酯含量。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 本标准可能涉及危险材料、操作和设备。本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 具体预防措施见第节 8. . 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 任何残留的脂肪酸和酯（FA＆E）应仅以极低的水平存在于纯甘油中。 4.2 该程序需要添加测量体积的氢氧化钠，超过与甘油样品中FA&E反应实际需要的量。 煮沸后，用标准盐酸反滴定多余的氢氧化钠。被滴定物质的数量是根据最初添加的氢氧化钠溶液的体积（通过空白滴定进行校正）与滴定剂在反滴定中消耗的体积之间的差值计算的。 注1: 氢氧化钠和盐酸的标准溶液可在市场上买到。

1.1 This test method provides the quantitative determination of the fatty acid and ester content in purified glycerin by the titrimetric method. 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 may involve hazardous materials, operations and equipment. 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. Specific precautions are listed in Section 8 . 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. ====== Significance And Use ====== 4.1 Any residual fatty acid and esters (FA&E) should be present only at very low levels in purified glycerine. 4.2 This procedure requires the addition of a measured volume of sodium hydroxide, in excess of the amount actually needed to react with FA&E in the glycerine sample. After boiling, the excess sodium hydroxide is back titrated with standardized hydrochloric acid. The quantity of the substance being titrated is calculated as the difference between the volumes of the sodium hydroxide solution originally added, corrected by means of a blank titration, and that was consumed by the titrant in the back titration. Note 1: The standardized solutions for sodium hydroxide and hydrochloric acid are commercially available.