1、Designation: D2108 10Standard Test Method forColor of Halogenated Organic Solvents andTheir Admixtures (Platinum-Cobalt Scale)1This standard is issued under the fixed designation D2108; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method cover
3、s the visual measurement of thecolor of halogenated organic solvents and their admixtures. Itis valid for values of 50 platinum-cobalt (Pt-Co) units or less.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 d
4、oes 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. Significance and Use2.1 Color m
5、ay be indicative of the quality of the solventbecause any color present is due to the presence of contami-nants.3. Apparatus3.1 Color Comparison TubesMatched 50 or 100-mL,tall-form Nessler tubes, provided with ground-on, opticallyclear, glass caps.3.2 Color ComparatorA color comparator constructed t
6、opermit visual comparison of light transmitted through tall-form, Nessler tubes in the direction of their longitudinal axes.The comparator should be constructed so that white light ispassed through or reflected off a white glass plate and directedwith equal intensity through the tubes and should be
7、shieldedso that no light enters the tubes from the side.3.3 Digital Color InstrumentDigital color instruments areavailable that measure color digitally and convert the result toa numerical value using the Platinum-Cobalt scale. Manymanufacturers market instruments of this type.NOTE 1There are numero
8、us colorimeters and comparators commer-cially available that measure the color of liquids and take some of thesubjectivity out of the measurement. These instruments may be calibratedwith the platinum-cobalt color standards listed in Table 1 at 455 mm orwith optically standardized color filter disks
9、such as those available for theHellige Aqua Tester. Many of these instruments take the measurementacross a relatively narrow range of wave lengths, and their readings maybe in error if the color of the sample is significantly different from theamber color of the color standards.4. Reagents4.1 Purity
10、 of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.2Other grades may beused, p
11、rovided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.4.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean distilled water or water ofequal purity.4.3 Cobaltous Chlo
12、ride (CoCl26H2O).4.4 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).4.5 Potassium Chloroplatinate (K2PtCl6).5. Preparation of Color Standards5.1 Platinum-Cobalt Stock SolutionDissolve 1.245 g ofK2PtCl6and 1.000 g of CoCl26H2O in water. Add 100 mL ofHCl (sp gr 1.19) and dilute to
13、 1 L with water. This solution hasa color of 500.NOTE 2Stock solutions of Pt-Co 500 color may be purchased fromreagent supply houses. The stock solution should be certified reagent orverified by the user as being correct.5.2 Platinum-Cobalt StandardsFor 100-mL Nesslertubes, prepare color standards a
14、s given in Table 1. Dilute therequired volumes of the stock solution with water to 100 mL in1This test method is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility of Subcommittee D26.04 on Test Methods.Current ed
15、ition approved Feb. 1, 2010. Published March 2010. Originallyapproved in 1962. Last previous edition approved in 2005 as D2108 05. DOI:10.1520/D2108-05.2Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents
16、notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C70
17、0, West Conshohocken, PA 19428-2959, United States.the Nessler tubes. Cap the tubes and seal the caps with shellacor a waterproof cement.5.3 For 50-mL Nessler tubes, prepare color standards byusing half the volume of stock solution given in Table 1. Thestock solution shall then be diluted with water
18、 to 50 mL in theNessler tubes. Cap the tubes and seal the caps with shellac ora waterproof cement.6. Procedure6.1 Introduce required sample volume into the Nessler tube,passing the sample through a filter if it has any visible turbidity.Cap the tube, place in the comparator, and compare with thestan
19、dards.7. Report7.1 Report the following information:7.1.1 Report as the color, the number of the standard thatmost nearly matches the sample. In the event that the color liesmidway between the two standards, report the darker of thetwo.7.1.2 If, owing to differences in hue between the sample andthe
20、standards, a definite match cannot be obtained, report therange over which an apparent match is obtained, and report thesample as “off-hue.”8. Precision and Bias38.1 PrecisionThe intralaboratory precision (one standarddeviation) of this test method is less than 2 Pt-Co units. Theinterlaboratory prec
21、ision is about 5 Pt-Co units (30 to 40 %relative standard deviation). The precision was determined by100-mL Nessler tubes.8.2 BiasThe bias of this test method was not determinedas a result of the lack of known standards of color in solvent.9. Keywords9.1 color; halogenated organic solvent; platinum-
22、cobaltscale; Pt-Co color; Pt-Co scaleASTM 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 validity of any such patent rights, and the ri
23、skof 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 comments are invited either for revision of th
24、is standard or for additional standardsand should be addressed to ASTM International Headquarters. 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
25、 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
26、 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 ASTM website (www.astm.org/COPYRIGHT/).3Research report available from ASTM Headquarters. Request RR:D26-1013.TABLE 1 Platinum-Cobalt Color StandardsColorStandardNumberStockSolution,mLColorStandardNumberStockSolution,mL51 35 710 2 40 815 3 50 1020 4 60 1225 5 70 1430 6 100 20500 100D2108 102
