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ASTM_D_5896_-_96_2012.pdf

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1、Designation:D589696(Reapproved 2012)Standard Test Method forCarbohydrate Distribution of Cellulosic Materials1This standard is issued under the fixed designation D5896;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last

2、revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the carbo-hydrate composition of cellulosic materials such as groundwood meal,chemi

3、cally refined pulp,mechanical pulps,brown-stocks,and plant exudates(gums)by ion chromatography.Thistest method is suitable for rapid,routine testing of largenumbers of samples with high accuracy and precision.For areview of this technique,see Lee(1).21.2 The values stated in SI units are to be regar

4、ded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine th

5、e applica-bility of regulatory limitations prior to use.For hazard state-ment,see Section 8.2.Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD1695 Terminology of Cellulose and Cellulose Derivatives3.Terminology3.1 For standard terminology of cellulose and cellulosederiv

6、atives,see Terminology D1695.3.2 Abbreviations:3.2.1 ICion chromatography,3.2.2 SPEsolid phase extraction,3.2.3 PADpulsed amperometric detector,3.2.4 PEDpulsed electrochemical detector,3.2.5 mMmillimolar.4.Summary of Test Method4.1 IC analysis of cellulosics requires the following opera-tions:(1)sam

7、ple preparation,(2)total hydrolysis,(3)dilution,(4)SPE,(5)ion chromatographic analysis,and(6)calibration/calculation.5.Significance and Use5.1 This test method requires total hydrolysis of carbohy-drate material to monosaccharides,and is thus applicable toany cellulosic or related material that unde

8、rgoes substantialhydrolysis,including cellulose derivatives such as celluloseacetate.5.2 The carbohydrate composition of a cellulosic materialcan be expressed on the basis of the total initial sample,or onthe basis of the carbohydrate portion of the sample.The formerrequires quantitative handling an

9、d may require special knowl-edge of the other components present in order to establish theabsolute carbohydrate level or determine individual woodhemicelluloses such as galactoglucomannan,etc.Since thesolid portion of purified pulps is almost all carbohydrate(98+%),the latter basis is often used to

10、express the carbo-hydrate distribution as a percent.5.3 If heated under alkaline conditions,isomeric sugars maybegin to appear in the chromatogram.The major impuritypresent in purified pulps is saccharinic acids.These acidiccomponents,and other anions such as sulfate,carbonate,andacetate are removed

11、 by a strong base anion exchange SPE,andwould need to be determined separately to get a more exactcarbohydrate distribution.6.Apparatus6.1 Blender.6.2 Screw Cap Culture Tubes,25 by 150 mm,outsidediameter.6.3 Refrigerator.6.4 Pressure Cooker.1This test method is under the jurisdiction of ASTM Committ

12、ee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.36 on Cellulose and Cellulose Derivatives.Current edition approved June 1,2012.Published August 2012.Originallyapproved in 1996.Last previous edition approved in 2007 as D5896-96(2007).

13、DOI:10.1520/D5896-96R12.2The boldface numbers in parentheses refer to the list of references at the end ofthis test method.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer t

14、o the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.5 SPE Cartridges.6.6 Water Bath.6.7 Ion Chromatograph.6.8 Moisture Balance.6.9 Hot Plate.6.10 Pipets.TOTAL HYDROLYSIS7.Reagents and

15、 Materials7.1 Sulfuric Acid(72 6 0.1 weight%):To 1 volume ofwater,add slowly while stirring vigorously 2 volumes ofconcentrated sulfuric acid(sp gr 1.84).Standardize against analkaline standard,and adjust to 72 6 0.1 weight%.8.Hazards8.1 Precaution:Wear eye protection and chemical resistantgloves wh

16、ile working with strong acid.9.Summary of Procedure9.1 The total hydrolysis of cellulosic material requires aprimary hydrolysis with strong mineral acid followed by asecondary hydrolysis in dilute acid.The primary hydrolysisresults in the formation of a mixture of oligosaccharides;thesecondary hydrolysis completes the conversion to monomericsugars.10.Sampling,Test Specimens,and Test Units10.1 Extract wood samples with ethanol to remove extrac-tives,then grind in a Wiley mill to pass a 40-mesh sc

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