1、Designation:D 3366 95(Reapproved 2003)e1Standard Test Method forColor of Maleic Anhydride and Phthalic Anhydride in theMolten State and After Heating(Platinum-Cobalt Scale)1This standard is issued under the fixed designation D 3366;the number immediately following the designation indicates the year
2、oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.e1NOTEEditorial changes were made throughout in February 2003.1.Scope1.1 T
3、his test method covers the determination of the visualmeasurement of the color of maleic and phthalic anhydridemelt before and after prolonged heating under specified con-ditions of time and temperature.Color values are expressed interms of platinum-cobalt standards.This test method covers therange
4、0 to 100 color standard numbers.1.2 The following applies to all specified limits in thisstandard:for purposes of determining conformance with thisstandard,an observed value or a calculated value shall berounded of“to the nearest unit”in the last right-hand digit usedin expressing the specification
5、limit,in accordance with therounding-off method of Practice E 29.1.3 This standard does 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
6、-bility of regulatory limitations prior to use.For specific hazardstatements see Section 7.2.Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water2D 1209 Test Method for Color of Clear Liquids(Platinum-Cobalt Scale)3D 3438 Practice for Sampling and Handling Naphthalene,Maleic
7、 Anhydride,and Phthalic Anhydride3E 29 Practice for Using Significant Digits in Test Data toDetermine Conformance With Specifications42.2Other Document:OSHA Regulations,29 CFR,paragraphs 1910.1000 and1910.120053.Summary of Test Method3.1 A freshly melted specimen is filled to mark into aNessler tube
8、 and compared with Platinum-Cobalt color stan-dards.3.2 After heating for 2 hours at a prescribed temperature,thespecimen is again compared to the color standards.4.Significance and Use4.1 The color of maleic anhydride and phthalic anhydridecan be an indication of the purity of these materials.Highc
9、olors normally indicate contamination.5.Apparatus5.1 Color Comparison TubesMatched sets of 50-mLNessler tubes having a total length of about 300 mm.Theheight of the 50-mL gradation mark shall be within 200 to 250mm above the exterior bottom of the tube.In a given set thegraduation marks shall not va
10、ry by more than 3 mm.The useof heat resistant glass is required.5.2 Color Comparator,constructed to permit visual com-parison of light transmitted through the 50-mL Nessler tubes inthe direction of their longitudinal axes.(The comparator shouldbe constructed so that white light is reflected off a wh
11、ite plateand directed with equal intensity through the tubes,and shouldbe shielded so that no light enters the tubes from the side.)NOTE1For convenience of operation,an electrically heated,insulatedcomparator tube may be used to prevent the solidification of maleic orphthalic anhydride.5.3 Electric
12、Heating BlockAn electrically heated alumi-num block,such as shown in Fig.1,having the followingoperating characteristics:1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.02 on Oxygenate
13、d Aromatics.Current edition approved Feb.10,2003.Published April 2003.Originallyapproved in 1974.Last previous edition approved in 1995 as D 3366 95.2Annual Book of ASTM Standards,Vol 11.01.3Annual Book of ASTM Standards,Vol 06.04.4Annual Book of ASTM Standards,Vol 14.02.5Available from U.S.Governme
14、nt Printing Office Superintendent of Documents,732 N.Capitol St.,NW,Mail Stop:SDE,Washington,DC 20401.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.Maleic anhydride temperature regulation,C140 6 2Heating time for specimen from 60 to 140
15、C,minutes25 6 5Phthalic anhydride temperature regulation,C250 6 2Heating time for specimen from 150 to 250C,minutes25 6 5Temperature gradient,specimen well to thermometer well,Cmax2The operating characteristics of the heating block used arecritical.6.Reagents6.1 Purity of ReagentsReagent grade chemi
16、cals 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,where such specifications are available.6Other 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 WaterUnless otherwise indicated referenceto water shall be understood
