Designation:D1106−21StandardTestMethodforAcid-InsolubleLignininWood1,2ThisstandardisissuedunderthefixeddesignationD1106;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethod3coversthedeterminationoftheacid-insolublelignincontentofwood.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.Specificprecautionarystatementsaregivenin6.1.1.3Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:4D1107TestMethodforEthanol-TolueneSolubilityofWood3.PrincipleofMethod3.1Whenwoodistreatedwithstrongacidsthecarbohy-dratesarehydrolyzed,leavinganinsolubleresiduewhichisdeterminedasacid-insolublelignin.Sincesomeofthewoodextractives(oils,resins,fats,waxes,tannins,gums,andstarch)wouldremaininsolublewiththelignin,thesearefirstremovedbyextractionwithsuitablesolvents.The72%sulfuricacidmethodforlignincontainstwoandsometimesthreeprelimi-naryextractivetreatmentsofthewood,namely:(1)withethanol,toremovethecatecholtannins;(2)withethanol-toluenesolution,toremovetheresins,oils,fatsandwaxes;and(3)withhotwater,toremovetheremainingwater-solublematerials.3.2Theethanolextractionisnecessaryinanalysisofwoodshighintannin;thatis,oak,chestnut,redwood,etc.Ithasnotbeenshownnecessaryinthemorecommonpulpwoods,suchasthevariousspeciesofspruce,pine,fir,hemlock,poplar,birch,beech,andmaple.Itisrecommendedthatforthesewoodsthealcoh...
