1、Designation: D5386 10Standard Test Method forColor of Liquids Using Tristimulus Colorimetry1This standard is issued under the fixed designation D5386; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A num
2、ber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers an instrumental method for theCIE (Commission International de lEclairage) tristimulusmeasurement of the color of
3、 near-clear liquid samples. Themeasurement is converted to color ratings in the platinum-cobalt system.1.2 This test method has been found applicable to the colormeasurement of clear, liquid samples, free of haze, withnominal platinum cobalt color values in the 0 to 100 range. Itis applicable to non
4、fluorescent liquids with light absorptioncharacteristics similar to those of the platinum cobalt colorstandard solutions. Test Methods D1686, D2108, and E450deal with the visual and instrumental measurement of near-clear liquids.1.3 In determining the conformance of the test results usingthis method
5、 to applicable specifications, results shall berounded in accordance with the rounding off methods ofPractice E29.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety
6、 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. For specific hazardstatements, see Section 8.2. Referenced Documents2.1 ASTM
7、 Standards:2D1193 Specification for Reagent WaterD1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)D1686 Test Method for Color of Solid Aromatic Hydrocar-bons and Related Materials in the Molten State (Platinum-Cobalt Scale)D2108 Test Method for Color of Halogenated OrganicSolvents
8、 and Their Admixtures (Platinum-Cobalt Scale)D3437 Practice for Sampling and Handling Liquid CyclicProductsD6809 Guide for Quality Control and Quality AssuranceProcedures for Aromatic Hydrocarbons and Related Ma-terialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance wi
9、th SpecificationsE179 Guide for Selection of Geometric Conditions forMeasurement of Reflection and Transmission Properties ofMaterialsE308 Practice for Computing the Colors of Objects byUsing the CIE SystemE313 Practice for Calculating Yellowness and WhitenessIndices from Instrumentally Measured Col
10、or CoordinatesE450 Method for Measurement of Color of Low-ColoredClear Liquids Using the Hunterlab Color DifferenceMeter3E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Other Document:OSHA Regulations, 29 CFR paragraphs 1910.1000 and1910.120043. Su
11、mmary of Test Method3.1 Color is measured by tristimulus values of light trans-mitted by a sample as percent of light transmitted by distilledwater. Convert the measured tristimulus values by appropriateequations to the platinum-cobalt scale.4. Significance and Use4.1 The major objective of the visu
12、al platinum-cobalt (Pt-Co) method of color measurement, as defined in Test MethodD1209, is to rate specific materials for yellowness. This1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D1
13、6.04 on Instrumental Analysis.Current edition approved Jan. 1, 2010. Published January 2010. Originallyapproved in 1993. Last previous edition approved in 2005 as D5386 05. DOI:10.1520/D5386-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
14、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from U.S. Government Printing Office Superintendent of Docume
15、nts,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.yellowness is frequently the
16、 result of the undesirable tendencyof liquid hydrocarbons to absorb blue light due to contamina-tion in processing, storage or shipping.4.2 Clear liquids can be rated for light absorbing yellowishor brownish contaminants, using scales that simulate thelong-established visual-comparison method just c
17、ited. Whereneeded, dimensions of color can be reported to identify anypinkness or greenness (one dimension), or grayness.5. Apparatus5.1 Instrument, with the following provisions:5.1.1 Instrument Sensor, shall provide a beam for illuminat-ing the sample cell in transmission. The instrument shall bec
18、apable of converting light measured in total transmissionthrough the sample cell to CIE X Y Z tristimulus color valuesfor the measurement conditions of CIE illuminant C and theCIE 1931 2 degree standard observer as described in GuideE179 and Practice E308.5.1.2 The CIE X Y Z tristimulus color values
19、 shall beconvertible to the instrumental yellowness index (YI) definedby Practice E308 and Practice E313. A correlation betweenmeasured yellowness index (YI) (Practice E313) values and thePt-Co standard solutions shall be used to yield an equivalentinstrumental Pt-Co rating for liquid hydrocarbon sa
20、mples.5.1.3 Sample Cells, shall have clear, colorless, parallelentrance and exit windows. Internal distance between facesshall be selectable. Path lengths from 20 to 150 mm have beenused for near-clear liquid hydrocarbons. If measuring samplesusing cells of the same path length, a path length tolera
21、nce of63 % or less would be appropriate. Matched cells would bebeneficial but not required.6. Reagents6.1 Purity 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 Analytic
22、al Reagents of the American Chemical Society,where such specifications are available.5Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 Purity of WaterReferences to water s
23、hall be under-stood to mean colorless distilled water, conforming to Type IVof Specification D1193.6.3 Cobalt Chloride, (CoCl26H2O).6.4 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).6.5 Potassium Chloroplatinate,(K2PtCl6).6.6 Platinum-Cobalt Stock SolutionDissolve 1.245 g ofpot
24、assium chloroplatinate (K2PtCl6) and 1.00 g of cobaltchloride (CoCl2H2O) in water. Carefully add 100 mL ofhydrochloric acid (HCl sp gr 1.19) and dilute to 1 L withdistilled water. The absorbance of the 500 platinum-cobaltstock solution in a cell having a 10-mm light path with distilledwater in a mat
25、ched cell as the reference solution must fallwithin the limits given in Table 1.7. Materials7.1 Platinum-Cobalt StandardsFrom the stock solutionprepare color standards in accordance with Table 2 by dilutingthe required volumes to 100 mL with water in volumetricflasks. When properly sealed and stored
26、 these standards arestable for at least one year. 500 APHA Platinum-Cobaltstandards may also be purchased.8. Hazards8.1 Consult current OSHA regulations, suppliers MaterialSafety Data Sheets, and local regulations for all materials usedin this test method.9. Sampling and Handling9.1 Refer to Practic
27、e D3437 for proper sampling and han-dling of liquid hydrocarbons analyzed by this test method.10. Calibration10.1 Prepare instrument for operation by following theinstrument manufacturers instructions.10.2 Use instrument standardizing adjustments or programto obtain a Pt-Co value of 0 for a sample o
28、f distilled water.10.3 It is advisable to read back distilled water to verify thatthe instrument reads a Pt-Co value of 0 as an operationalqualification (OQ) step.10.4 Run QA samples to verify the analytical system is incontrol. It is desirable for the user to be able to adjust theinstrument to matc
29、h the Pt-Co standard solutions as defined in7.1.11. Procedure11.1 Check to be sure that the instrument is operating inaccordance with the manufacturers operations manual.11.2 Take three (3) instrumental readings without samplereplacement, with the average taken as being a representativePt-Co measure
30、ment of the sample. Exercise care to avoidsample contamination.12. Report12.1 Report the following information:12.1.1 Sample identification, and12.1.2 Instrumental Pt-Co measurement to nearest wholeunit.5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washingto
31、n, DC. For suggestions on the testing of reagents 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.TABLE 1 Absorb
32、ance Tolerance Limits for No. 500 Platinum-Cobalt Stock SolutionWavelength Absorbance430 0.110 to 0.120455 0.130 to 0.145480 0.105 to 0.120510 0.055 to 0.065D5386 10213. Precision and Bias613.1 PrecisionInstrument correlations to the Pt-Co ColorScale are based on measuring the corresponding Yellowne
33、ssIndex of Pt-Co liquid color standards as defined in Test MethodD1209. However, regular samples often exhibit a slight greenor red off-hueness or scattering haze, or both, relative to thePt-Co liquid color standards that can result in instruments ofdifferent models and manufacture reading near iden
34、tical onPt-Co liquid color standards but not on samples. This precisionstatement accommodates all of the expected variables ininstrumental Pt-Co color measurement of regular samples andPt-Co liquid standards to the Pt-Co 100 level.13.1.1 A higher precision may be achieved than is listedbelow by usin
35、g the same measurement method and instrumentsmodel or measuring samples, or both, that are optically clearand are near identical in yellowness to the Pt-Co liquidstandards.13.1.2 The data for determining the precision of this testmethod are based on the analyses of o-xylene, styrene, andtoluene samp
36、les at approximate values of 2, 12, 17, 63, and 127respectively, and Pt-Co liquid standards at levels of approxi-mately 0, 10 and 254 and 498 were also included in the roundrobin. Nineteen (19) laboratories participated in this studyusing instruments from all of the major transmission geom-etries (0
37、:t, 8:t, 0:0) and using transmission cells of differentpath lengths (10, 20, 33, 50, 100 mm).13.2 Under the guidelines of Practice E691, the followingcriteria should be used to judge the acceptability (95 %probability) of results obtained by this test method. The criteriawere derived from a round ro
38、bin between nineteen laborato-ries. Each of the samples was run on three different days ineach laboratory.13.2.1 Intermediate Precision to Pt-Co 100 LevelBasedon an intermediate precision standard deviation of 0.44 +0.0057 (Pt-Co reading), two single test results obtained fromtwo samples of the same
39、 material in the same laboratory by thesame operator and on the same instruments in a short period oftime should not differ by more than 1.23 + 0.0161 (Pt-Coreading).Y=mX+b Y=Intermediate precision X = Platinum Cobalt Readingb = y-intercept m = slopeY = 0.0057 X +0.44 Intermediate precision SDY = 0.
40、0161 X +1.23 Intermediate precision at 95 % confidence level13.2.2 Reproducibility to Pt-Co 100 LevelBased on areproducibility standard deviation of 1.64 + 0.0552 (Pt-Coreading), two test results from samples of the same materialfrom different laboratories should not differ by more than 4.60+ 0.1546
41、 (Pt-Co reading).Y=mX+b Y=Reproducibility X = Platinum Cobalt Readingb = y-intercept m = slopeY = 0.0552 X +1.64 Reproducibility SDY = 0.1546 X +4.60 Reproducibility at 95 % confidence level13.3 BiasThe bias of this test method cannot be deter-mined because no referee method is available to determin
42、e thetrue value.14. Quality Guidelines14.1 Laboratories shall have a quality control system inplace.14.1.1 Confirm the performance of the test instrument ortest method by analyzing a quality control sample followingthe guidelines of standard statistical quality control practices.14.1.2 A quality con
43、trol sample is a stable material isolatedfrom the production process and representative of the samplebeing analyzed.14.1.3 When QA/QC protocols are already established inthe testing facility, these protocols are acceptable when theyconfirm the validity of test results.14.1.4 When there ar no QA/QC p
44、rotocols established in thetesting facility, use the guidelines described in Guide D6809 orsimilar statistical quality control practices.15. Keywords15.1 APHA; Hazen; hydrocarbons; instrumental color mea-surement; Pt-Co; platinum-cobalt; tristimulus6Supporting data have been filed at ASTM Internatio
45、nal Headquarters and maybe obtained by requesting Research Report RR: D16-1012.TABLE 2 Platinum-Cobalt Color StandardsColor StandardNumberStock Solution, mLColor StandardNumberStock Solution mL1 0.20 10 2.002 0.40 11 2.203 0.60 12 2.404 0.80 13 2.605 1.00 14 2.806 1.20 15 3.007 1.40 20 4.008 1.60 25
46、 5.009 1.80 30 6.00D5386 103SUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to this standard since the last issue (D5386 - 05)that may impact the use of this standard. (Approved January 1, 2010.)(1) Added information on units to the Scope section 1.4.(2) Added Guide D
47、6809 to the list of Referenced Documents section 2.1.(3) Added a section on Quality Guidelines Section 14.ASTM 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 tha
48、t 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 reviewed every five years andif not revised, either reappro
49、ved 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 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 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
