1、Designation: D4902 99 (Reapproved 2016)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 la
2、st 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
3、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 spen
4、tmaterials 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 therespo
5、nsibility 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:2D4903 Test Method for Total Solids and Water in VegetableTanning Material ExtractsD6401 Test
6、 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
7、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 soli
8、ds, 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
9、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 labo
10、ratories.5. Apparatus5.1 Drying OvenForced-air convection oven (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
11、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.6. Procedure6.1 The thermometer having been checked and the ovenproperly regulated, place the tare
12、d evaporating dishes contain-ing the aliquots of solution, or of hide powder, or of raw orspent tanning materials, to be dried in the oven and allow toremain there for 17 6 1h.6.2 When drying is complete, remove the dishes from theoven, place in desiccators, cool to room temperature, andweigh to the
13、 nearest 0.1 mg.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, Method A13 of the OfficialMethods of the American Leather Chemists Ass
14、ociation.Current edition approved Sept. 1, 2016. Published October 2016. Originallyapproved in 1989. Last previous edition approved in 2009 as D4902 99 (2009).DOI: 10.1520/D4902-99R16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm
15、.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
16、 452210014.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17. Keywords7.1 drying; evaporation; moisture; tannin analysis; veg-etable tannin analysisASTM International takes no position respecting the validity of any patent rights asse
17、rted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by
18、 the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will recei
19、ve careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Inter
20、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 99 (2016)2
