1、Designation: D 5351 93 (Reapproved 2009)Standard Test Method forDetermination of Organically Combined Sulfuric Anhydrideby Extraction Titration, Test Method B1This standard is issued under the fixed designation D 5351; the number immediately following the designation indicates the year oforiginal ad
2、option 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 the determination of the organi-cally combined
3、 sulfuric anhydride existing in a sample ofsulfated oil by extracting the undecomposed sulfated fat andother fatty matter over an acidulated, concentrated salt solu-tion, boiling the residue with sulfuric acid after evaporating thesolvent, and titrating the products of reaction. This test methodis a
4、pplicable only to sulfated oils that split off their combinedSO3upon boiling with mineral acids, including samplescontaining sodium acetate or other compounds that cannot beaccurately titrated in water solution with methyl orange as theindicator. This test method was derived from Test MethodsD 500,
5、Sections 20 through 24, and ALCA Method H-43.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is therespon
6、sibility 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 500 Test Methods of Chemical Analysis of Sulfonatedand Sulfated Oils2.2 Other Document:ALCA
7、 Method H-43 Organically Combined Sulfuric Anhy-dride Extraction Titration Test (for Sulfated Oils)33. Significance and Use3.1 This test method is intended for the determination oforganically combined sulfuric anhydride in sulfated oils.4. Apparatus4.1 The apparatus required consists of a glass flas
8、k providedwith a glass stopper and an air condenser. The connectionbetween the flask and the condenser shall be a ground joint.Perforated glass beads shall be used to prevent bumping.4.1.1 Flask, an Erlenmeyer flask (Fig. 1) made of borosili-cate glass, having a capacity of approximately 300 mL, and
9、provided with a glass stopper.4.1.2 CondenserThe condenser required consists of aglass tube, 915 mm (36 in.) in length, and 8 mm (516 in.) inoutside diameter. The lower end of the tube shall be flared andground to fit the mouth of the Erlenmeyer flask.4.1.3 Glass Beads, perforated glass beads, made
10、of chemi-cally resistant glass, approximately 4 mm (532 in.) in diameter.Before using, the glass beads shall be boiled thoroughly inseveral portions of water or until the wash water reacts neutralto methyl orange indicator.5. Reagents5.1 Ethyl Ether:5.2 Methyl Orange Indicator Solution (1 g/L)Dissol
11、ve 0.1g of methyl orange in 100 mL of water.5.3 Sodium Chloride (NaCl), solid.5.4 Sodium Hydroxide, Standard Solution (1 N)Accurately prepare and standardize a 1 N sodium hydroxide(NaOH) solution. Express the strength or concentration of thesolution as milligrams of KOH per millilitre; 1 mL of 1 NNa
12、OH solution is equivalent to 56.1 mg of KOH.5.5 Sodium Hydroxide, Standard Solution (0.5 N)Accurately prepare and standardize a 0.5 N NaOH solution.Express the strength of the solution as milligrams of KOH permillilitre; 1 mL of 0.5 N NaOH solution is equivalent to 28.05mg of KOH.5.6 Sulfuric Acid (
13、1 + 19)Carefully mix one volume ofconcentrated sulfuric acid (H2SO4, sp gr 1.84) into 19 volumesof water while stirring.5.7 Sulfuric Acid Standard (0.5 N)Accurately prepareand standardize as 0.5 N sulfuric acid (H2SO4) solution.Express the strength of the solution as milligrams of KOH permillilitre;
14、 1 mL of 0.5 N H2SO4is equivalent to 28.05 mg ofKOH.1This test method is under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.08 on Fats and OilsCurrent edition approved April 1, 2009. Published July 2009. Originallyapproved in 1993. Last previo
15、us edition approved in 2003 as D 5351 93 (2003).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.3Available fr
16、om American Leather Chemists Assn., Texas Tech University, P.O.Box 45300, Lubbock, TX 79409.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Procedure6.1 The procedure consists of isolating and purifying thefatty matter as it exist
17、s in the original oil by dissolving thesample in a solvent, acidifying and washing with saturatedbrine, and determining the increase in acidity upon boiling theisolated product with sulfuric acid. This increase in acidity isdesignated as F.6.1.1 Separation of Purified OilWeigh5to10gofthesample, depe
18、nding upon the concentration of the fatty matter,into a 250-mL separatory funnel containing 50 mL of concen-trated NaCl solution, some solid NaCl, five drops of methylorange indicator solution, and 50 mL of ether. Shake themixture and neutralize with H2SO4(1 + 19) until the lowerlayer is distinctly
19、pink (about 0.2 mL in excess). Highlysulfated oils at this stage may form three layers instead of two.In such cases, use a fat solvent consisting of a mixture of twoparts of ether and one part of alcohol. Allow the mixture in theseparatory funnel to settle for at least 5 min, draw off the lowerlayer
20、 into another separatory funnel, and wash the ether layerwith 25-mL portions of NaCl solution until practically neutralto methyl orange, that is, until one drop of 0.5 N NaOHsolution turns the wash water strongly alkaline. Allow allseparations to settle for at least 5 min. Combine the waterlayers, a
21、nd extract with two 25-mL portions of ether. Combinethe last two ether extractions and wash with NaCl solution untilfree from acid, as in the case of the ether layer in the firstfunnel. Combine all the ether layers in the decomposition flaskand evaporate the ether.6.1.2 Increase in Acidity upon Boil
22、ing, FDetermine theincrease in acidity upon boiling in accordance with theprocedure described for Test Method A in 6.1.2. Reserve thetitrated solution for the subsequent determination of totaldesulfated fatty matter (Sections 20 to 24 of Test MethodsD 500). Make a blank determination as described fo
23、r TestMethod A in 6.1.1. Calculate the increase in acidity F inaccordance with 6.1.2.7. Calculation7.1 Calculate the percentage of organically combined sul-furic anhydride as follows:Organically combined sulfuric anhydride, % 5 0.1426 3 Fwhere:0.1426 = one tenth the molecular ratio of SO3: KOH, andF
24、 = increase in acidity upon boiling.8. Precision and Bias8.1 Although this test method is widely used, precision andbias information is not available at this time.9. Keywords9.1 extraction; leather; sulfated oils; sulfuric anhydride;titrationASTM International takes no position respecting the validi
25、ty of any patent rights asserted 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 subjec
26、t 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 comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarte
27、rs. Your comments will receive 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
28、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).FIG. 1 Apparatus for Determination of Organically CombinedSulfuric Anhydride, Method AD 5351 93 (2009)2
