1、Designation: D3366 18Standard Test Method forColor of Maleic Anhydride in the Molten State and AfterHeating (Platinum-Cobalt Scale)1This standard is issued under the fixed designation D3366; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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. Scope*1.1 This test method covers the determination of the visualmeasurement of the color of maleic anhydri
3、de melt before andafter prolonged heating under specified conditions of time andtemperature. Color values are expressed in terms of platinum-cobalt standards.1.2 This test method covers the range 0 to 100 colorstandard numbers.1.3 In determining the conformance of the test results usingthis method t
4、o applicable specifications, results shall berounded off in accordance with the rounding-off method 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 thesafet
5、y concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific hazard statements see Sections 7, 10.2.1, and10
6、.4.2.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarrie
7、rs to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM 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
8、)D3438 Practice for Sampling and Handling Naphthalene,Maleic Anhydride, and Phthalic AnhydrideD6809 Guide for Quality Control and Quality AssuranceProcedures for Aromatic Hydrocarbons and Related Ma-terialsD8005 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)E29 Practice for Using Sig
9、nificant Digits in Test Data toDetermine Conformance with SpecificationsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 Other Document:3OSHA Regulations, 29 CFR paragraphs 1910.1000 and1910.12003. Summary of Test Method3.1 A specimen is melted at 6
10、0C.3.2 A freshly melted specimen is filled to mark into aNessler tube and compared with Platinum-Cobalt color stan-dards.3.3 After heating for2hat140C, the specimen is againcompared to the color standards.4. Significance and Use4.1 The color of maleic anhydride can be an indication ofthe purity of t
11、hese materials. High colors normally indicatecontamination or decomposition. This test method is suitablefor setting specifications and for use as an internal qualitycontrol tool.5. Apparatus5.1 Color Comparison TubesMatched 100-mL, tall-formNessler tubes, provided with ground-on, optically clear, g
12、lass1This test method is under the jurisdiction of ASTM Committee D16 onAromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-bility of Subcommittee D16.02 on Oxygenated Aromatics.Current edition approved Feb. 1, 2018. Published June 2018. DOI: 10.1520/D3366-18. Last previ
13、ous edition approved in 2003 as D3366-95(2003)1which waswithdrawn January 2012 and reinstated in February 2018.2For 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 s
14、tandards Document Summary page onthe ASTM website.3Available from U.S. Government Printing Office, Superintendent ofDocuments, 732 N. Capitol St., NW, Washington, DC 20401-0001, http:/www.access.gpo.gov.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 10
15、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and R
16、ecommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1caps. Tubes should be selected so that the height of the 100-mLgraduation mark is 300 6 3 mm above the bottom of the tube.The use of heat resistant tubes is preferred for safety reasons.5.2 Color Compa
17、rator, constructed to permit visual com-parison of light transmitted through tall-form, 100-mL Nesslertubes in the direction of their longitudinal axes. The compara-tor should be constructed so that white light is reflected off awhite plate and directed with equal intensity through the tubes,and sho
18、uld be shielded so that no light enters the tubes from theside.5.3 OvenAn oven, preferably of the forced draft type andcapable of maintaining a constant temperature 61C in therange up to 140C. Alternatively the use of an aluminumheating block provided with proper temperature control orother similar
19、equipment is permissible.6. Reagents and Materials6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall the reagents should conform to the specifications of theCommittee on Analytical Reagents of the American ChemicalSociety, wher
20、e such specifications are available.4Other gradesmay be used, provided it is first ascertained that the reagent isof sufficiently high purity to permit its use without lesseningthe accuracy of the determination.6.2 Purity of WaterReferences to water shall be under-stood to mean water, conforming to
21、Type IV of SpecificationD1193.6.3 Cobalt Chloride, (CoCl26H2O).6.4 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).6.5 Potassium Chloroplatinate, (K2PtCl6).7. Hazards7.1 Consult current OSHA regulations, suppliers SafetyData Sheets, and local regulations for all materials used in
22、 thistest method.7.2 WarningWhen handling molten solids in open tubes,adequate ventilation must be provided and proper protectionshould be used to prevent thermal burns.8. Sampling and Handling8.1 Sample the material in accordance with Practice D3438.9. Calibration and Standardization9.1 Platinum-Co
23、balt Stock SolutionDissolve 1.245 g ofK2PtCl6and 1.000 g of CoCl26H2O in water. Add 100 mL ofHCl and dilute to 1 L with water. This solution is defined ascolor standard No. 500. The absorbance of the 500 Platinum-Cobalt Stock Solution in a cell having a 10-mm light path withdistilled water in a matc
24、hed cell as the reference solution mustfall within the limits given in Table 1.9.2 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 these standa
25、rds arestable for at least one year. 500 Platinum-Cobalt standards mayalso be purchased.10. Procedure10.1 Melt approximately 150-g specimen and simultane-ously preheat a Nessler tube and cap in an oven, electricheating block, or other similar equipment held at a temperatureof 60C for maleic anhydrid
26、e.10.2 As soon as the specimen is completely liquid, mix bystirring with a clean, dry, glass rod; then quickly fill thepreheated Nessler tube to the 100-mL mark with the specimenand cap the tube. Place the tube in the comparator andimmediately compare with the standards and record as thecolor of the
27、 specimen in the molten state.10.2.1 Use caution and wear appropriate safety equipmentwhen handling hot samples and equipment.10.2.2 Report as the color, the number of the standard thatmost nearly matches the specimen. For samples between 20and 100 PtCo color, estimate the color between the standard
28、sbelow and above the specimen.10.3 Place the filled Nessler tube in an oven, electric heatingblock, or other similar equipment which has been regulated at140C (61C). Allow the tube to remain in the block for 2 h4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, W
29、ashington, 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
30、1 Absorbance 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 0.065TABLE 2 Platinum-Cobalt Color StandardsColor StandardNumberStock Solution,mLColor StandardNumberStock Solution,mL1 0.20 19 3.802 0.40 2
31、0 4.003 0.60 25 5.004 0.80 30 6.005 1.00 35 7.006 1.20 40 8.007 1.40 45 9.008 1.60 50 10.009 1.80 55 11.0010 2.00 60 12.0011 2.20 65 13.0012 2.40 70 14.0013 2.60 75 15.0014 2.80 80 16.0015 3.00 85 17.0016 3.20 90 18.0017 3.40 95 19.0018 3.60 100 20.00D3366 182(which includes 90 min at the test tempe
32、rature). Protect tubesadequately from contamination during the test period.10.4 Remove the tube, place in the comparator, and imme-diately compare with the standard. Record as the color afterheating in the molten state.10.4.1 Report as the color, the number of the standard thatmost nearly matches th
33、e specimen. For samples between 20and 100 Pt-Co color, estimate the color between the standardbelow and above the sample.10.4.2 Use caution and wear appropriate safety equipmentwhen handling hot samples.10.5 In no case apply this test method if the moltenspecimen contains any visible turbidity.11. R
34、eport11.1 Report the following information:11.1.1 Report (1) color in the molten state, and (2) color inthe molten state after heating.11.1.2 Report as the color, the number of the standard thatmost nearly matches the specimen. In the event that the colorlies midway between two standards, estimate t
35、he color.11.1.3 If, owing to differences in hue between the specimenand the standard, an exact match cannot be attained, but anestimate is possible, report the range over which an approxi-mate match is obtained, and report the specimen as “off hue.”11.1.4 If, owing to large differences in hue betwee
36、n thespecimen and the standards, no estimate is possible, report thespecimen as “no match.”12. Precision and Bias512.1 The precision of this test method is based on anintralaboratory study of Test Method D3366 conducted in2017. One laboratory tested one Maleic Anhydride sample forColor in the Molten
37、 State and After Heating Using VisualMeasurement. Every test result represents an individual deter-mination. The laboratory reported 20 replicate results for eachanalysis/material combination in order to estimate the repeat-ability limits of the standard. Practice E691 was followed forthe design and
38、 analysis of the repeatability data; the details aregiven in Research Report RR:D16-1066.12.1.1 Repeatability Limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for that material; “r” is theinterval representing the critica
39、l difference between two testresults for the same material, obtained by the same operatorusing the same method on the same day in the same laboratory.12.1.1.1 Repeatability limits are listed in Table 3 and Table4.12.1.2 Reproducibility has not been determined and will bedetermined within five years.
40、12.2 BiasSince there is no acceptable reference material,bias has not been determined.13. Quality Guidelines13.1 Laboratories shall have a quality control system inplace.13.1.1 Confirm the performance of the test instrument ortest method by analyzing a quality control sample followingthe guidelines
41、of standard statistical quality control practices.13.1.2 A quality control sample is a stable material isolatedfrom the production process and representative of the samplebeing analyzed.13.1.3 When QA/QC protocols are already established inthe testing facility, these protocols are acceptable when th
42、eyconfirm the validity of test results.13.1.4 When there are no QA/QC protocols established inthe testing facility, use the guidelines described in GuideD6809 or similar statistical quality control practices.14. Keywords14.1 maleic anhydride; platinum-cobalt color5Supporting data have been filed at
43、ASTM International Headquarters and maybe obtained by requesting Research Report RR:D16-1066. ContactASTM CustomerService at serviceastm.org.TABLE 3 Repeatability Limits(Maleic Anhydride in the Molten State at 60C)VisualMeasurementAverageXRepeatabilityStandardDeviationSrRepeatabilityLimitrNumber(Pla
44、tinum-CobaltScale)8 0.5 1TABLE 4 Repeatability Limits(Maleic Anhydride after Heating at 140C)VisualMeasurementAverageXRepeabatilityStandardDeviationSrRepeatabilityLimitrNumber(Platinum-CobaltScale)18 1.3 4D3366 183SUMMARY OF CHANGESCommittee D16 has identified the location of selected changes to thi
45、s standard since the last issue(D3366-95(2003)1) that may impact the use of this standard. (Approved February 1, 2018.)(1) This standard applies to maleic anhydride only. Phthalicanhydride is used less in chemical industry.(2) Warning of hazard was added in Section 7, 10.2.1, and10.4.2.(3) The absor
46、bance tolerance limits for No. 500 Platinum-Cobalt Stock Solution was set in 9.1 to verify the referencesolution.(4) The Platinum-Cobalt Color Standards were defined in 9.2from the range of 1 to 100 platinum-cobalt number.(5) Precision and Bias was required in Section 12 based on anintralaboratory s
47、tudy. The laboratory reported 20 replicateresults for each analysis/material combination in order toestimate the repeatability limits of the standard.(6) Section 13 Quality Guidelines was added.ASTM International takes no position respecting the validity of any patent rights asserted in connection w
48、ith 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 subject to revision at any time by the responsible tec
49、hnical 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 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 copyr
