ASTM_D_4902_-_99_2020.pdf

Designation:D490299(Reapproved 2020)Standard Test Method forEvaporation and Drying of Analytical Solutions1This standard is issued under the fixed designation D4902;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.1.Scope1.1 This test method covers a procedure for the evaporatingand drying of the 100 mL portions of analytical solutionobtained in the methods for vegetable tannin analysis,so thatconsistent results may be obtained for the determination oftotal solids,soluble solids,and non-tannins in the sample.Thistest method is also intended for use in determining the moisturein the hide powder samples and the moisture in raw and spentmaterials in the methods for vegetable tannin analysis.1.2 The values stated in SI units are to be regarded 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4903 Test Method for Total Solids and Water in VegetableTanning Material ExtractsD6401 Test Method for Determining Non-Tannins and Tan-nin in Extracts of Vegetable Tanning MaterialsD6402 Test Method for Determining Soluble Solids andInsolubles in Extracts of Vegetable Tanning MaterialsD6403 Test Method for Determining Moisture in Raw andSpent Materials2.2 ALCA Methods:A13 Evaporation and Drying of Analytical Solutions33.Summary of Test Method3.1 This test method describes a procedure for evaporationand drying of the 100 mL portions of the analytical solutionobtained in Test Methods D4903,D6401,and D6402,so thatconsistent results may be obtained for the determination oftotal solids,soluble solids,and non-tannins in the sample.Thistest method is also intended for use in determining the moisturein the air-dry and prepared,wet,hide powders used in TestMethod D6401,and the moisture in raw and spent materials inTest Method D6403.4.Significance and Use4.1 This test method is useful for determining the solidresidue in analytical solutions.4.2 Because of the possibility of unknown errors in this testmethod,it is essential that the procedure be followed exactly inorder to obtain reproducible results,both among specimenswithin a laboratory and for analyses between laboratories.5.Apparatus5.1 DryingOvenForced-airconvectionoven(ormechanical-convection draft oven)capable of maintaining atemperature of 100 6 2.0C.5.2 ThermometerAccurate to 6 0.2C,should be used tocheck and monitor the oven set point.5.3 Desiccators and Desiccant:5.3.1 The desiccators used can be of any convenient form orsize,but should be at least 4 in.in diameter for a single tannindish.5.3.2 Any normal desiccating agent such as calcium sulfate,calcium chloride,or silica gel may be used.1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.01 on Vegetable Leather.Thismethod has been adapted from,and is a replacement for,MethodA13 of the OfficialMethods of the American Leather Chemists Association.Current edition approved Dec.1,2020.Published December 2020.Originallyapproved in 1989.Last previous edition approved in 2016 as D4902 99(2016).DOI:10.1520/D4902-99R20.2For 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.3Official Methods of the American Leather Chemists Association.Availablefrom the American Leather Chemists Association,University of Cincinnati,P.O.Box 210014,Cincinnati,OH 452210014.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.16.Procedure6.1 The thermometer having been checked and the ovenproperly regulated,place the tared evaporating dishes contain-ing the aliquots of solution,or of hide powder,or of raw orspent tanning materials,to