【国外标准】 Standard Test Method for Carbohydrate Distribution of Cellulosic Materials

5.1 This test method requires total hydrolysis of carbohydrate material to monosaccharides, and is thus applicable to any cellulosic or related material that undergoes substantial hydrolysis, including cellulose derivatives such as cellulose acetate.5.2 The carbohydrate composition of a cellulosic material can be expressed on the basis of the total initial sample, or on the basis of the carbohydrate portion of the sample. The former requires quantitative handling and may require special knowledge of the other components present in order to establish the absolute carbohydrate level or determine individual wood hemicelluloses such as galactoglucomannan, etc. Since the solid portion of purified pulps is almost all carbohydrate (98 +  %), the latter basis is often used to express the carbohydrate distribution as a percent.5.3 If heated under alkaline conditions, isomeric sugars may begin to appear in the chromatogram. The major impurity present in purified pulps is saccharinic acids. These acidic components, and other anions such as sulfate, carbonate, and acetate are removed by a strong base anion exchange SPE, and would need to be determined separately to get a more exact carbohydrate distribution.1.1 This test method covers the determination of the carbohydrate composition of cellulosic materials such as ground wood meal, chemically refined pulp, mechanical pulps, brownstocks, and plant exudates (gums) by ion chromatography. This test method is suitable for rapid, routine testing of large numbers of samples with high accuracy and precision. For a review of this technique, see Lee (1).21.2 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. For hazard statement, see 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.