1、Designation:D98205(Reapproved 2009)Technical Association of Pulpand Paper IndustryStandard Method T 418 os-61Standard Test Method forOrganic Nitrogen in Paper and Paperboard1This standard is issued under the fixed designation D982;the number immediately following the designation indicates the year o
2、foriginal adoption or,in the case of revision,the year of last 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 nitrog-enous organic
3、 materials in paper and paperboard,whichtypically are used to reduce the thermal degradation of thecellulose in the paper and paperboard.1.2 The nitrogen determination by this method does notinclude the nitrogen in nitro compounds,nitrates,nitrites,azo,hydrazine,cyanide,or pyridine ring-type compoun
4、ds,none ofwhich are normally found in paper and paperboard.There is noknown modification of the method that is applicable to allnitrogenous compounds.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.2.Referenced Documents2.1 A
5、STM Standards:2D585 Practice for Sampling and Accepting a Single Lot ofPaper,Paperboard,Fiberboard,and Related Product(Withdrawn 2010)3D644 Test Method for Moisture Content of Paper andPaperboard by Oven Drying(Withdrawn 2010)33.Summary of Test Method3.1 This test method is a modification of the wel
6、l-knownKjeldahl procedure.In this test method,compounds that yieldtheir nitrogen as ammonia are digested with concentratedsulfuric acid,using sodium sulfate to raise the boiling point,and mercuric oxide as a catalyst.The organic matter isdestroyed and the nitrogen is fixed as ammonium sulfate in the
7、excess acid.4.Significance and Use4.1 The purpose of this test method is to determine theamount of organic nitrogen present within a sample of electri-cal insulation paper or paperboard.Nitrogen content is used todetermine if the paper or paperboard has been chemicallytreated to withstand higher tha
8、n normal operating tempera-tures.Such a paper or paperboard is referred to in the industryas“thermally upgraded.”A paper or paperboard that is ther-mally upgraded can withstand higher operating temperaturesand allow the electrical equipment to have a longer useful lifespan.5.Apparatus5.1 Kjeldahl Ap
9、paratus,with 500 or 800-mL flask and adigestion rack,an efficient bulb or scrubber type of trap toensure that no nonvolatile alkali is carried over,the trap beingconnected to the flask with a rubber stopper and to thewater-cooled condenser following,with rubber tubing.Thecondenser tube shall be made
10、 of alkali-resistant glass or blocktin with the discharge end connected to a bent glass deliverytube,the lower end of which is drawn out to a bore of about 3mm.5.2 Other Apparatus500-mL Erlenmeyer flask,100-mLgraduated cylinder,50-mLburet,and mossy zinc or glass beadsfor the flask to prevent bumping
11、.6.Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.4Other g
12、rades are alsoacceptable,provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the
13、direct responsibility ofSubcommittee D09.19 on Dielectric Sheet and Roll Products.Current edition approved Oct.1,2009.Published February 2010.Originallyapproved in 1948.Last previous edition approved in 2005 as D982 05.DOI:10.1520/D0982-05R09.2For referenced ASTM standards,visit the ASTM website,www
14、.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Reagents Chemicals,American Chemical S
15、ociety Specifications,”Am.Chemi-cal Soc.,Washington,DC.For suggestions on the testing of reagents not listed bytheAmerican Chemical Society,see“Reagent Chemicals and Standards,”by JosephRosin,D.Van Nostrand Co.,Inc.,New York,NY,and the“United StatesPharmacopeia.”Copyright ASTM International,100 Barr
16、 Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.2 Purity of WaterUnless otherwise indicated,referencesto water shall be understood to mean distilled water or water ofequal purity.6.3 Boric Acid and Indicator SolutionDissolve 43 g ofboric acid(H3BO3)(free from borax),6 mL of methyl redindicator,and 4 mL of methylene blue indicator,each 0.1 g in100 mL of 95%ethyl alcohol,per litre of freshly distilledwater.Keep the solution in a borosilicate glass bottle.It isstable for
