1、Designation: D 2617 06Standard Test Method forTotal Ash in Leather1This standard is issued under the fixed designation D 2617; 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 indic
2、ates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of total ash inleather.1.2 This standard does not purport to address all of thesafety concerns, if any, associated with
3、 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:2D 2807 Test Method for Chromic Oxide in Leather (Per-chloric Acid Ox
4、idation)D 2813 Practice for Sampling Leather for Physical andChemical Tests3. Summary of Test Method3.1 The sample is ignited in air at 600 6 25C until constantmass is attained. The weighed residual matter is termed “ash”and is calculated as a percentage of the original sample.4. Significance and Us
5、e4.1 This test method is useful in determining the approxi-mate amount of nonvolatile inorganic material in leather. Thismay be in the form of salts or oxides of the elements. In amixed chrome tannage, the approximate percentage of otherelements in the leather may be determined by subtracting thechr
6、omic oxide that may be conveniently determined on the ash.(See Test Method D 2807.)4.2 The temperature of 600C specified is high enough toproduce a reproducible result but it does not completelydehydrate such oxides as aluminum oxide, (Al2O3) and chro-mic oxide (Cr2O3). Likewise, such salts as sulfa
7、tes andphosphates may be incompletely dehydrated, and if alkaliesand chromium are present simultaneously, oxidation to chro-mate may occur. Therefore, caution is advised in drawingconclusions based on quantitative relations of the elements.5. Apparatus5.1 Crucible, 30 to 50-mL, high-form, platinum o
8、r porce-lain.5.2 Electric Muffle Furnace, with controller or rheostat andpyrometer, capable of maintaining a temperature of 600 625C.6. Test Specimen6.1 The specimen shall consist of 1 to5gofleather from thecomposite sample prepared in accordance with an acceptedprocedure.3NOTE 1In some leathers, si
9、licones or other organometallic complexesthat are solvent, soluble, and ash producing are used. It may be desirableto obtain ash on an extracted sample, and if so, it should be indicated onthe report.7. Procedure7.1 Weigh accurately (to 1 mg) into a tared crucible 1 to 5g of leather, prepared as des
10、cribed in 6.1, and preferably atsufficiently close equilibrium with the laboratory humidity thatit does not gain or lose mass at a significant rate. Place thecrucible and sample in the muffle furnace and maintain at 6006 25C for at least 15 min after the absence of char or glowingembers, to destroy
11、carbonaceous matter (Note 2). Remove thecrucible from the furnace, cool in a desiccator, and weigh(Note 3). Replace in the furnace and maintain at 600 6 25Cfor another 15 min. Repeat the weighing operation. Continueheating for 15 min and weighing as described above until amass constant within 0.2 mg
12、 is obtained. Record the final mass.NOTE 2The above procedure is satisfactory with most leathers. Withheavily oiled or stuffed leather, start with a cold muffle and raisetemperature gradually to 600C, or burn off the oil carefully over a gasburner before placing the crucible in the hot furnace.NOTE
13、3If it is difficult to burn off the carbon, as evidenced byinspection or failure to achieve constant mass, moisten the ash with a fewdrops of 1+1 nitric acid, dry carefully over a low flame, and then transferto the muffle and heat as before. If this procedure is unsuccessful, digestthe ash in the cr
14、ucible with 15 to 20 mL of hot water for a few minutes,and filter the suspension through an ashless high-retention filter paper.1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.06 on Chemical Analysis. Thistest method wa
15、s developed in cooperation with the American Leather ChemistsAssn. (Standard Method B 15 1969).Current edition approved Oct. 1, 2006. Published November 2006. Originallyapproved in 1969. Last previous edition approved in 2001 as D 2617 96 (2001).2For referenced ASTM standards, visit the ASTM website
16、, 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.3Acceptable procedures are published in the Journal of the American LeatherChemists Association, Vol 51, 1956, p. 4
17、97; see Practice D 2813.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Transfer the paper and insoluble residue to the crucible and ignite at 6006 25C as described above. Cool, add the filtrate to the crucible,evaporate carefully to
18、 dryness, then ignite at 600 6 25C to constant massas described above.8. Calculations8.1 Calculate the percentage of ash in the leather weighed asfollows:Ash, % 5 A 2 B!/C 2 B!# 3 100 (1)where:A = mass of the ash and crucible,B = mass of the crucible, andC = mass of the sample and crucible.8.2 If it
19、 is desired to convert the percentage obtained aboveto the dry basis, perform a moisture determination on a portionof the same sample weighed under the same conditions as inSection 7. If the percentage moisture found is D, then calculatethe percentage of ash on a dry basis as follows:Ash, dry basis,
20、 % 5 A 2 B!/C 2 B!# 3 100/1 2 D/100!# (2)where A, B, and C have the same meaning as in 8.1.8.3 The ash may be determined on a sample conditioned asto temperature and relative humidity. In this case, weigh thesample under identically controlled temperature and humidity,and report the results in such
21、a manner as to indicate this fact,for example:Ash X C, Y % relative humidity! 5 Z % (3)9. Precision and Bias49.1 PrecisionThe precision of this test method is largelylimited by the homogeneity of the sample in a complex naturalmaterial such as leather.9.1.1 RepeatabilityAt the 95 % confidence level,
22、 dupli-cate determinations by the same operator should not differ bymore than 0.14 % ash.9.1.2 ReproducibilityAt the 95 % confidence level, theaverage of duplicate determinations in each of two laboratoriesby different operators should not differ by more than 0.20 %ash.9.2 BiasInasmuch as all leathe
23、rs contain an unknownamount of natural or inherent ash, no meaningful statement canbe made with respect to bias.10. Keywords10.1 aluminum oxide; ash; chromic oxideASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this s
24、tandard. 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 the responsible technical committee and must be re
25、viewed 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 receive careful consideration at a meeting of therespons
26、ible 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 International, 100 Barr Harbor Drive, PO Box C700, West
27、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).4The precision and bias statements are based on data filed at the ASTMHeadquarters as RR 89: D-31.D2617062
