1、Designation: D 6406 99 (Reapproved 2004)Standard Test Method forAnalysis of Sugar in Vegetable Tanning Materials1This standard is issued under the fixed designation D 6406; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates 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 determining the sugars presentin vegetable tanning materials.1.2 The values stated in SI un
3、its are to be regarded as thestandard. The inch-pound units given in parentheses are forinformation only.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 and
4、 health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 4901 Practice for Preparation of Solution of Liquid Veg-etable Tannin ExtractsD 4905 Practice for Preparation of Solution of Solid, Pasty,and Powdered Vegetable Tann
5、in ExtractsD 6401 Test Method for Determining Non-Tannins andTannin in Extracts of Vegetable Tanning MaterialsD 6403 Test Method for Determining Moisture in Raw andSpent MaterialsD 6404 Practice for Sampling Vegetable Materials Contain-ing TanninD 6405 Practice for Extraction of Tannins from Raw and
6、Spent MaterialsD 6408 Test Method for Analysis of Tannery Liquors2.2 ALCA Methods:A30 Sugar in Tanning Materials33. Terminology3.1 Definitions:3.1.1 dextrosed-glucose.3.1.2 glucosea simple sugar with formula C6H12O6, andknown to exist in d-, l-, and racemic forms. The termcommonly refers to the swee
7、t, colorless, water-soluble dex-trorotatory form that occurs widely in nature and is the usualform in which carbohydrate is assimilated by animals. Theterm glucose can also refer to a light-colored syrup made fromcorn starch.3.1.3 sugarany of various water-soluble compounds thatvary widely in sweetn
8、ess and comprise the oligosaccharidesincluding sucrose.4. Summary of Test Method4.1 An analytical strength solution (that is, 4.00 6 0.25 gtannin per litre) of the tanning material is analyzed for reducingsugars and total sugars by the Munson and Walker procedure.5. Significance and Use5.1 This test
9、 method is used to determine the quantity ofsugar present in vegetable tanning materials or vegetabletannin extracts. The amount of the reducing sugars, totalsugars, and non-reducing sugars in a sample of material orextract can be determined by this method.5.2 Because of the possibility of errors in
10、 this test method itis essential that the method be followed exactly in order toobtain reproducible results both among specimens within alaboratory and for analyses between laboratories.6. Apparatus and Reagents6.1 Saturated Solution of Normal Lead Acetate.6.2 Dipotassium Hydrogen Phosphate, Anhydro
11、us(K2HPO4), dried in an oven at 100C for 16 h then stored in atightly stoppered bottle.6.3 Toluene, assay $ 99.5 %.6.4 Fehlings Solutions, A and B.6.5 Hydrochloric Acid, concentrated (sp.gr. 1.18).6.6 Kerosene, commercial grade.6.7 Saturated Solution of Sodium Hydroxide.6.8 Phenolphthalein Solution,
12、 0.5 g dissolved in 100 mL of95 % ethanol.6.9 Tartaric Acid, powdered.6.10 Copper Sulfate Solution, prepared by dissolving69.278 g of CuSO45H2O in 1 L of distilled water and filteringthrough asbestos.1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct respon
13、sibility of Subcommittee D31.01 on Vegetable Leather. Thismethod has been adapted from and is a replacement for Method A30 of the OfficialMethods of the American Leather Chemists Association.Current edition approved April 1, 2004. Published May 2004. Originallyapproved in 1999. Last previous edition
14、 approved in 1999 as D 6406 99.2For 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 Ameri
15、can Leather Chemists Association. Availablefrom the American Leather Chemists Association, University of Cincinnati, P.O.Box 210014, Cincinnati, OH 45221-0014.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.11 Alkaline Tartrate Sol
16、ution, prepared by dissolving 346g of Rochelle salt (sodium potassium tartrate tetrahydrate) and100 g of sodium hydroxide in 1 L of distilled water. Afterstanding for two days the solution shall be filtered throughasbestos.6.12 Alcohol, 95 % ethyl alcohol.6.13 Ether, diethyl ether.6.14 Filter Paper4
17、, 21.5 cm diameter, pleated to contain 32evenly divided creases.6.15 Funnel, 100-125 mm top diameter, 60 angle bowl, and150 mm stem length.6.16 Watch Glasses, a suitable size (approximately 150 mmdiameter) to be used as a cover for the funnel and filter paper.6.17 Graduated Cylinder, standard labora
18、tory grade with500 mL capacity.6.18 Pipets, capable of measuring and transferring 100 mL,50 mL, and 7.5 mL.6.19 Beakers, 400 mL, low form.6.20 Erlenmeyer Flasks, 500 mL capacity.6.21 Reflux Condensers, to connect to the top of theErlenmeyer flasks.6.22 Heat Source, either a Bunsen burner or a hotpla
19、te.6.23 Volumetric Flasks, 200 mL capacity.6.24 Filtering Crucibles, either porcelain crucibles of Fineporosity or Gooch-asbestos crucibles prepared as follows:6.24.1 Digest finely divided long fibered asbestos with nitricacid (diluted 1 to 3) for 2 to 3 days.6.24.2 Wash the asbestos free from acid.
20、6.24.3 Digest the asbestos with 10 % sodium hydroxidesolution for two to three days.6.24.4 Wash the asbestos free from alkali.6.24.5 Prepare the Gooch crucible by making a bottom layerof 6.4 mm (14 in.) thickness using the coarser particles ofasbestos on the bottom and dress off the mat with the fin
21、erasbestos particles.6.24.6 Wash the mat with boiling Fehlings solution.6.24.7 Wash the mat with nitric acid diluted 1 to 3.6.24.8 Wash and rinse the mat with hot distilled water.6.24.9 Crucibles so prepared can be used for a long time.6.25 Suction Flask and Crucible Holder, with connectionsto a vac
22、uum.6.26 Balance, analytical balance which will weigh up to 100g with an accuracy of 6 0.1 mg (6 0.0001 g).6.27 Drying Oven, a forced-air convection oven (ormechanical-convection draft oven) capable of maintaining atemperature of 100 6 2.0C.6.28 Thermometer, accurate to 6 0.2C used to check andmonit
23、or the oven set point.6.29 Dessicator, any convenient form or size, using anynormal desiccant.7. Test Specimen7.1 The specimen for the sugar analysis shall consist of 400mL of a solution of the tanning material of analytical strength(4.006 0.25 g tannin per L).8. Procedure8.1 Sample the tanning mate
24、rial using Practice D 6404, andprepare the analytical solution as described in PracticesD 4901, D 4905, D 6405,orD 6408.8.2 Detannization of Analytical Solution:8.2.1 Add to 400 mL of the analytical solution 50 mL of asaturated lead acetate solution. Shake the mixture well andallow to stand for 5 to
25、 10 min.NOTE 1It is important that the mixture of liquor and lead acetatesolution be very well shaken. Good results are obtained by placing thesolution mixture in shake bottles and running in the shake machine for 10min (as described in Test Method D 6401) to ensure complete detanniza-tion of the li
26、quor. The mixture filters better after complete detannization.Complete detannization also results in less danger of residual quantities ofunreacted lead which may exceed the capacity of the potassium phosphateto remove and which could then interfere in the final copper precipitationstep.8.2.2 Then f
27、ilter the mixture through a folded filter paperand return the filtrate to the filter until it is clear. Continuefiltration until 360 to 380 mL of the clear filtrate has beencollected; this may take an hour or more to accomplish. Coverthe funnel during the filtration.8.2.3 Measure the volume of the c
28、ollected filtrate in agraduated cylinder. Remove the excess lead from this filtrateby adding dried dipotassium hydrogen phosphate (K2HPO4)atthe rate of 2.5 g (6 0.1 g) phosphate per 100 mL of the filtrate.After addition of the phosphate shake the mixture well for 4 to5 min and then filter through a
29、folded filter paper. Allow timefor the solution to drain completely from the lead phosphate.Cover the funnel during the filtration.8.3 Determination of Reducing Sugars:8.3.1 Add to 100 mL of the clarified (de-tanned) andde-leaded filtrate solution obtained from 8.2.3 33.3 mL ofdistilled water. If th
30、e reduction is not to be made at once alsoadd eight to ten drops of toluene. Shake this mixture well andstopper with a plug of cotton. Keep the prepared solution in acool place and make the reduction within 24 h. When ready forreduction, filter the solution if toluene has been added. Deter-mine redu
31、cing sugars by the Munson and Walker procedure in8.4 using duplicate 50 mL aliquots.8.4 Munson and Walker Method for Sugar Analysis:8.4.1 Measure a 50 mL aliquot by pipet into a 400 mLbeaker containing a mixture of 25 mL of the alkaline tartratesolution and 25 mL of the copper sulfate solution and c
32、over thebeaker. Heat this mixture to 100C, as indicated by a thermom-eter, in exactly 4 min and continue boiling for exactly 2 min.8.4.1.1 Regulate the rate of heating before the determinationis started by adjusting the burner or hotplate so that 50 mL ofwater, 25 mL of the tartrate solution, and 25
33、 mL of the coppersulfate solution in a 400 mL beaker will be heated to 100C inexactly 4 min.8.4.2 Filter the solution, without dilution, immediatelythrough a tared crucible. Wash the residue thoroughly with hotwater, then with alcohol, and finally with ether. Prepare the4The sole source of supply of
34、 S glucose analysis; sugar analysis;tannin analysis; vegetable tannin analysisASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the valid
35、ity 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 reviewed every five years andif not revised, either reapproved or withdrawn. Your comme
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37、ot 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 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).D 6406 99 (2004)6
