ASTM_D_465_-_15.pdf

Designation:D46515Standard Test Methods forAcid Number of Pine Chemical Products Including Tall Oiland Other Related Products1This standard is issued under the fixed designation D465;the number immediately following the designation indicates the year oforiginal 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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These test methods are intended for determining the acidnumber of pine chemical products as defined in TerminologyD804 including tall oil products,wood and gum rosin,andother related materials.These test methods may not be appli-cable to all modified rosin products.Two test methods arecovered,as follows:1.1.1 Potentiometric method(referee),and1.1.2 Internal indicator method(alternate).1.2 The potentiometric method is suitable for use with bothlight-and dark-colored products.It should be considered thereferee method.The internal indicator method is suitable foruse only with light-and medium-colored products with aGardner color of less than 12.It should be considered thealternate method.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4 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 the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D803 Test Methods for Testing Tall OilD804 Terminology Relating to Pine Chemicals,IncludingTall Oil and Related ProductsE70 Test Method for pH of Aqueous Solutions With theGlass ElectrodeE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Significance and Use3.1 These test methods are designed to broaden the scope ofthe earlier editions of the test method by the inclusion of tall oiland tall oil derived products as test materials and will bereferenced in Test Methods D803.3.2 The acid number is an important property of pinechemical products,such as tall oil,and the products obtainedby the fractionation of tall oil.It is the test method widely usedto determine the total free acid content of these products.3.3 The potentiometric test method should be used when themost reproducible results are required.4.Preparation of Sample4.1 If the sample for analysis is rosin,it shall consist ofsmall pieces of rosin chipped from a freshly exposed part of alump or lumps,and thereafter crushed to facilitate weighingand dissolution.Prepare the sample the same day on which thetest is begun,in order to avoid changes in properties due tosurface oxidation.This is very pronounced on ground rosinhaving a large surface area exposed to the air.Existing rosindust and powdered rosin must not be used.4.2 If the sample is a nonhomogenous liquid,heat the entiresample in a closed container fitted with a capillary vent or theequivalent.Some kind of agitation,even if done occasionallyby hand,saves much time.Heat by immersion in open steam orhot water bath to avoid overheating.When dealing withcrystallized rosin a temperature of approximately 160C maybe needed.Sampling should take place only when the entiresample is homogeneous and has been well stirred.4.3 For other products no special preparation is necessaryexcept storage in a closed container prior to testing.1These test methods are under the jurisdiction of ASTM Committee D01 onPaint and Related Coatings,Materials,and Applications and are the directresponsibility of Subcommittee D01.34 on Pine Chemicals and HydrocarbonResins.Current edition approved Dec.1,2015.Published December 2015.Originallyapproved in 1937.Last previous edition approved in 2010 as D465 05(2010).DOI:10.1520/D0465-15.2For 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 to 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 4.4 Guideline for sample size,solvent,and titrant:SampleSample Size,gSolvent I,mLSolvent II,mLTitrant,KOHFatty acidsDTOARosin soap4.0 0.05Isopropylalcohol,ormethanol100None0.5NFA esters20 0.1Isopropylalcohol,ormethanol100None0.1NRosinCTOAPitch4.0 0.05Toluene 25Isopropylalcohol 750.5NRosin esters10 0.1 g10 0.1Toluene 25Isopropylalcohol 750.1NADTO represents distilled tall oil,while CTO represents crude tall oil.5.Purity of Reagents and Water5.1 Unless otherwise indicated,it is intended that all re-agents shall conform to the specifications established by theCommittee on An