ASTM_D_4903_-_99_2009.pdf

Designation:D490399(Reapproved 2009)Standard Test Method forTotal Solids and Water in Vegetable Tanning MaterialExtracts1This standard is issued under the fixed designation D4903;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 is intended for use in determining thetotal solids and water in extracts of vegetable tanning materi-als.The test method is applicable to solutions of liquid,solid,pasty,and powdered extracts and to extracts of raw or spentmaterials.1.2 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:2D4901 Practice for Preparation of Solution of Liquid Veg-etable Tannin ExtractsD4902 Test Method for Evaporation and Drying of Analyti-cal SolutionsD4905 Practice for Preparation of Solution of Solid,Pastyand Powdered Vegetable Tannin 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 MaterialsD6404 Practice for Sampling Vegetable Materials Contain-ing TanninD6405 Practice for Extraction of Tannins from Raw andSpent Materials2.2 ALCA Methods:A20 Total Solids and Water33.Summary of Test Method3.1 An aliquot of the prepared analytical solution is pipettedinto an evaporating dish and evaporated to dryness in a forcedair oven.4.Significance and Use4.1 The test method is useful in determining the total solidsand water in analytical solutions.5.Apparatus5.1 Tannin DishCrystallizing dish,borosilicate glass,50mm tall,70 mm outside diameter.The bottom corner shall berounded to a radius of 6 mm,the bottom shall be flat and notcupped in the center,and the top edge shall be rounded andpolished.5.2 Pipet,100-mL capacity,preferably with a wide orificeapproximately 2.4 mm(332in.)diameter and 15 to 25-sdelivery time.5.3 Drying OvenA forced-air convection oven(ormechanical-convection draft oven)capable of maintaining atemperature of 100 6 2.0 C.5.4 ThermometerAccurate to 6 2.0 C,used to check andmonitor the oven set point.5.5 DessicatorAny convenient form or size.6.Test Specimen6.1 The specimen shall consist of 100 mL of a solutionprepared as described in Practices D4901,D4905,and D6405.7.Procedure7.1 Thoroughly mix the solution,prepared as described inPractices D4901,D4905,and D6405,by inverting and shaking1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.01 on Vegetable Leather Thistest method has been adapted from and is a replacement for Method A20 of theOfficial Methods of the American Leather Chemists Association.Current edition approved April 1,2009.Published July 2009.Originallyapproved in 1989.Last previous edition approved in 2004 as D490399(2004).DOI:10.1520/D4903-99R09.2For 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 45221.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8 to 10 times,taking care to ensure that all insoluble matter isuniformly dispersed and none left adhering to the walls of theflask.Immediately,pour a 150-mLto 250-mLportion(approxi-mately)into a bottle or other suitable container,stoppered orcovered,and retain until the soluble solids and non-tannins areready to be pipetted(see Practice D6404).Where the analysisis being performed in a constant temperature room,however,the specimen may be pipetted from this portion at anyconvenient time.At the proper time,thoroughly mix thissecondary portion by shaking,or stirring,so that the insolublematter is uniformly distributed throughout the liquor and noneremains adhering to the walls of the container.Immediatelyrinse the 100-mL pipet with the liquor rejecting the rinsings.Then stir the liquor well avoiding production of air bubbles andfoam,and while stirring immerse the tip of the rinsed pipet andfill pipet quickly by suction.Bring the level to the mark asquickly as possible,and transfer the 100-mL specimen into atared evaporating dish.(Since tan liquors are very liable tofoam and since they may contain large amounts of rapid-settling insoluble matter,conduct the final mixing,so