ASTM D3366-18

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D3366 − 18
Standard Test Method for
Color of Maleic Anhydride in the Molten State and After
Heating (Platinum-Cobalt Scale)
This standard is issued under the fixed designation D3366; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* D1209 Test Method for Color of Clear Liquids (Platinum-
Cobalt Scale)
1.1 This test method covers the determination of the visual
D1686 Test Method for Color of Solid Aromatic Hydrocar-
measurement of the color of maleic anhydride melt before and
bons and Related Materials in the Molten State (Platinum-
after prolonged heating under specified conditions of time and
Cobalt Scale)
temperature. Color values are expressed in terms of platinum-
D3438 Practice for Sampling and Handling Naphthalene,
cobalt standards.
Maleic Anhydride, and Phthalic Anhydride
1.2 This test method covers the range 0 to 100 color
D6809 Guide for Quality Control and Quality Assurance
standard numbers.
Procedures for Aromatic Hydrocarbons and Related Ma-
terials
1.3 In determining the conformance of the test results using
this method to applicable specifications, results shall be D8005 Test Method for Color of Clear Liquids (Platinum-
Cobalt Scale)
rounded off in accordance with the rounding-off method of
Practice E29. E29 Practice for Using Significant Digits in Test Data to
Determine Conformance with Specifications
1.4 The values stated in SI units are to be regarded as
E691 Practice for Conducting an Interlaboratory Study to
standard. No other units of measurement are included in this
Determine the Precision of a Test Method
standard.
2.2 Other Document:
1.5 This standard does not purport to address all of the
OSHA Regulations, 29 CFR paragraphs 1910.1000 and
safety concerns, if any, associated with its use. It is the
1910.1200
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
3. Summary of Test Method
mine the applicability of regulatory limitations prior to use.
3.1 A specimen is melted at 60°C.
For specific hazard statements see Sections 7, 10.2.1, and
3.2 A freshly melted specimen is filled to mark into a
10.4.2.
Nessler tube and compared with Platinum-Cobalt color stan-
1.6 This international standard was developed in accor-
dards.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
3.3 After heating for2hat 140°C, the specimen is again
Development of International Standards, Guides and Recom-
compared to the color standards.
mendations issued by the World Trade Organization Technical
4. Significance and Use
Barriers to Trade (TBT) Committee.
4.1 The color of maleic anhydride can be an indication of
2. Referenced Documents
the purity of these materials. High colors normally indicate
2.1 ASTM Standards:
contamination or decomposition. This test method is suitable
D1193 Specification for Reagent Water
for setting specifications and for use as an internal quality
control tool.
This test method is under the jurisdiction of ASTM Committee D16 on
5. Apparatus
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi-
bility of Subcommittee D16.02 on Oxygenated Aromatics.
5.1 Color Comparison Tubes—Matched 100-mL, tall-form
Current edition approved Feb. 1, 2018. Published June 2018. DOI: 10.1520/
ε1
Nessler tubes, provided with ground-on, optically clear, glass
D3366-18. Last previous edition approved in 2003 as D3366-95(2003) which was
withdrawn January 2012 and reinstated in February 2018.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Available from U.S. Government Printing Office, Superintendent of
Standards volume information, refer to the standard’s Document Summary page on Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://
the ASTM website. www.access.gpo.gov.
*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
D3366 − 18
caps.Tubesshouldbeselectedsothattheheightofthe100-mL Cobalt Stock Solution in a cell having a 10-mm light path with
graduation mark is 300 6 3 mm above the bottom of the tube. distilled water in a matched cell as the reference solution must
The use of heat resistant tubes is preferred for safety reasons. fall within the limits given in Table 1.
5.2 Color Comparator, constructed to permit visual com-
TABLE 1 Absorbance Tolerance Limits for No. 500 Platinum-
parison of light transmitted through tall-form, 100-mL Nessler
Cobalt Stock Solution
tubes in the direction of their longitudinal axes. The compara-
Wavelength Absorbance
tor should be constructed so that white light is reflected off a
430 0.110 to 0.120
white plate and directed with equal intensity through the tubes,
455 0.130 to 0.145
andshouldbeshieldedsothatnolightentersthetubesfromthe
480 0.105 to 0.120
side. 510 0.055 to 0.065
5.3 Oven—An oven, preferably of the forced draft type and
capable of maintaining a constant temperature 61°C in the
9.2 Platinum-Cobalt Standards—From the stock solution
range up to 140°C. Alternatively the use of an aluminum
prepare color standards in accordance with Table 2 by diluting
heating block provided with proper temperature control or
the required volumes to 100 mL with water in volumetric
other similar equipment is permissible.
flasks. When properly sealed and stored these standards are
6. Reagents and Materials stable for at least one year. 500 Platinum-Cobalt standards may
also be purchased.
6.1 Purity of Reagents—Reagent grade chemicals shall be
used in all tests. Unless otherwise indicated, it is intended that
10. Procedure
all the reagents should conform to the specifications of the
10.1 Melt approximately 150-g specimen and simultane-
Committee on Analytical Reagents of the American Chemical
ously preheat a Nessler tube and cap in an oven, electric
Society, where such specifications are available. Other grades
heating block, or other similar equipment held at a temperature
may be used, provided it is first ascertained that the reagent is
of 60°C for maleic anhydride.
of sufficiently high purity to permit its use without lessening
the accuracy of the determination.
10.2 As soon as the specimen is completely liquid, mix by
stirring with a clean, dry, glass rod; then quickly fill the
6.2 Purity of Water—References to water shall be under-
preheated Nessler tube to the 100-mL mark with the specimen
stood to mean water, conforming to Type IV of Specification
and cap the tube. Place the tube in the comparator and
D1193.
immediately compare with the standards and record as the
6.3 Cobalt Chloride, (CoCl ·6H O).
2 2
color of the specimen in the molten state.
6.4 Hydrochloric Acid (sp gr 1.19)—Concentrated hydro- 10.2.1 Use caution and wear appropriate safety equipment
chloric acid (HCl). when handling hot samples and equipment.
10.2.2 Report as the color, the number of the standard that
6.5 Potassium Chloroplatinate, (K PtCl ).
2 6
most nearly matches the specimen. For samples between 20
and 100 Pt–Co color, estimate the color between the standards
7. Hazards
below and above the specimen.
7.1 Consult current OSHA regulations, supplier’s Safety
10.3 PlacethefilledNesslertubeinanoven,electricheating
Data Sheets, and local regulations fo
...