1、Designation: D 848 03Standard Test Method forAcid Wash Color of Industrial Aromatic Hydrocarbons1This standard is issued under the fixed designation D 848; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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. Scope*1.1 This test method covers the determination of the a
3、cidwash color of benzene, toluene, xylenes, refined solventnaphthas, and similar industrial aromatic hydrocarbons.1.2 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 s
4、afety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see Sections 8 and 12.1.2. Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water2D 3437 Practice for Sampling and Handling Liquid CyclicProducts3
5、D 4790 Terminology of Aromatic Hydrocarbons and Re-lated Chemicals32.2 Other Document:OSHA Regulations. 29 CFR, paragraphs 1910.1000 and1910.120043. Terminology3.1 See Terminology D 4790 for definitions of terms used inthis test method.4. Summary of Test Method4.1 A mixture of the aromatic hydrocarb
6、on and sulfuric acidis vigorously shaken and the color of the acid layer is comparedwith that of color standards prepared from CoCl2and FeCl3.5. Significance and Use5.1 This test method is suitable for setting specifications onthe materials referenced in 1.1. It may also be used as aninternal qualit
7、y control tool and in development or researchwork.5.2 The color developed in the acid layer gives an indicationof impurities which if sulfonated would cause the material tobe discolored.6. Apparatus6.1 Containers for Color StandardsClear and unblem-ished, clean, French square, flint-glass, flat-bott
8、om, glass-stoppered, 1-oz capacity bottles holding 31 to 33 mL whenfilled to the neck.5The bottles shall be labeled with thereference number of the color standard they contain (see 11.2).6.2 Test ContainersContainers exactly like those de-scribed in 6.1 except that each French square bottle shall be
9、marked by etching to show when the bottle contains thevolume of 7 and 28 mL, respectively. Colored crayons andsimilar markers shall not be used for marking the bottles.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thata
10、ll reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.6Other grades may beused provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lesseni
11、ng theaccuracy of the determination.1This test method is under the jurisdiction of ASTM Committee D16 onAromatic Hydrocarbons and Related Chemicals and is the direct responsibility ofSubcommittee D16.01 on Benzene, Toluene, Xylenes, Cyclohexane and TheirDerivatives.Current edition approved June 10,
12、2003. Published July 2003. Originallyapproved in 1945. Last previous edition approved in 2002 as D 848 02.2Annual Book of ASTM Standards, Vol 11.01.3Annual Book of ASTM Standards, Vol 06.04.4Available from Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.5The sole so
13、urce of supply of the apparatus known to the committee at this timeis Ramin USA Corporation, 39019 FM 149 Rd., Magnolia, TX 77354. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meet
14、ingof the responsible technical committee, which you may attend.6Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals,
15、 BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.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, P
16、A 19428-2959, United States.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean distilled water, Type I orII as described in Specification D 1193.7.3 Cobalt Chloride (CoCl26H2O).7.4 Ferric Chloride (FeCl36H2O).7.5 Hydrochloric Acid (1 + 39)Mix 25 mL of hydro
17、chlo-ric acid (31 weight % HCl) with 975 mL of water.7.6 Potassium Chromate (K2CrO4).7.7 Potassium Dichromate (K2Cr2O7).7.8 Sulfuric Acid (96 60.5 weight % H2SO4).7.9 Sulfuric Acid (78 60.5 weight % H2SO4).8. Hazards8.1 Consult current OSHA regulations, suppliers MaterialSafety Data Sheets, and loca
18、l regulations for all materials usedin this test method.8.2 When handling strong acids or acid cleaning solutions,wear proper personnel protective equipment.9. Sampling9.1 Sample the material in accordance with PracticeD 3437.10. Cleaning of Containers10.1 Clean new containers (Section 6) with a cle
19、aningsolution that will not impact the results, such as a chromic acidsubstitute, rinse with tap water followed by distilled water, anddry in an oven set at a minimum of 105C for at least 1 h.Likewise, clean all other glassware used in this test method.11. Preparation of Reference Color StandardsNOT
20、E 1Purchase of solutions or reference color standards, or both, isallowed. The user of this standard assumes the responsibility of ensuringany purchased solutions or standards are prepared with materials that meetthe requirements expressed in the Reagents section of this standard.Likewise, the user
21、of this standard assumes the responsibility of ensuringany purchased solutions or standards are prepared as expressed in thissection.11.1 Stock SolutionsPrepare the following basic reagentsolutions for use in preparing the reference color standards:11.1.1 Solution ADissolve 59.50 g of CoCl26H2OinHCl
22、(1 + 39) and make up to 1 L in a volumetric flask with HCl(1 + 39).11.1.2 Solution BDissolve 45.054 g of FeCl36H2OinHCl (1 + 39) and make up to 1 L in a volumetric flask with HCl(1 + 39).11.1.3 Solution CMix 312 volumes of Solution A with3612 volumes of Solution B and dilute with 90 volumes ofwater.
23、11.1.4 Solution DMix 312 volumes of Solution A with3612 volumes of Solution B.11.1.5 Solution EPrepare an aqueous solution of K2CrO4saturated at 21C.11.1.6 Solution FPrepare an aqueous solution of K2Cr2O7saturated at 21C and dilute with an equal volume of water.11.2 Prepare reference color standard
24、solutions having thefollowing compositions and numbered as specified below. It isnot required to make each color standard. Only those referencecolor standards that bracket the samples being evaluated mustbe utilized.No. 0Distilled water.No. 11 volume of Solution C plus 1 volume of water.No. 2512 vol
25、umes of Solution C plus 2 volumes of water.No. 3Solution C.No. 41 volume of Solution D plus 1 volume of water.No. 5512 volumes of Solution D plus 2 volumes of water.No. 6Solution D.No. 75 volumes of Solution E plus 2 volumes of water.No. 8Solution E.No. 97 volumes of Solution E plus12 volume of Solu
26、tion F.No. 10612 volumes of Solution E plus 1 volume of Solution F.No. 11512 volumes of Solution E plus 2 volumes of Solution F.No. 121 volume of Solution E plus 1 volume of Solution F.No. 132 volumes of Solution E plus 5 volumes of Solution F.No. 14Solution F.11.3 Rinse the No. 0 container (5.1) an
27、d its glass stopperthree times with water, fill with water, and stopper. Rinse theNo. 1 container and its stopper three times with reference colorstandard solution No. 1 (Section 11.2), fill with this solution,and stopper. In this way, prepare the set of containers of colorstandards from 0 through 1
28、4 having the compositions shownfor the corresponding color solution standards in 11.2. Whenfilling the French square bottles, leave14 in. (6 mm) of vaporspace below the neck of the bottle. Seal each container withparaffin to prevent loss by evaporation or seepage.NOTE 2It is recommended color standa
29、rds be prepared annually fromfresh solutions.12. Procedure12.1 Fill a clean, dry test container to the 7-mL mark withthe acid of the strength specified in Table 1 for the type ofsample to be tested . Add sufficient sample to bring the totalvolume to the 28-mL mark (Note 3). Insert the stopper, hold
30、afinger over the stopper, and give vigorous shakes with a strokeof 13 to 25 cm (5 to 10 in.), shaking for a total of 150 cyclesover a period of 40 to 50 s, that is at a rate of 3 to 3.75 cycles/s.(Use of an automatic shaker is allowed given it can be shownto produce comparable results to the manual
31、technique.)(WarningConcentrated sulfuric acid will cause severe burnson contact with the skin. As a precaution the test containershould be wrapped in a towel or enclosed in a plastic bagduring the shaking period. The test should be performed usingappropriate personal protective equipment.)NOTE 3If t
32、he room temperature is above 85F, maintain the acid,sample, and reference color standards at a temperature between 77 andTABLE 1 Acid Strengths and Standing TimesSampleSulfuricAcidStrength,%StandingTime,minGroup 1 Benzene, all ASTM gradesToluene, all ASTM gradesXylene, nitration gradeXylene, 5Xylene
33、, 10Any other more highly refinedproducts96 15Group 2 Xylene, industrial gradeRefined solvent naphtha96 5Group 3 Hi-flash solventHeavy solvent naphtha78 5D84803285F (25 and 29C) through the test, and insulate the test container insome convenient way, such as wrapping with a cloth, during the shaking
34、period.12.2 Allow the container to stand, protected from directsunlight, for the period of time shown in Table 1. Withoutfurther delay, invert the container gently once or twice toobtain a uniform color in the acid layer, and compare the colorof the acid layer with that of the standards (11.3). Make
35、 thecomparison against a white background or against daylight,using transmitted light (Note 4). When testing samples inGroup 1 (Table 1), observe the color of the oil layer as well asthat of the acid layer. Standards used shall include standardsone number above and one number below the sample, excep
36、tfor the samples reading 0 or 14.NOTE 4Agreement of results may be improved by using a colorcomparator of a suitable type for observing the color of the acid layer incomparison with the reference standard color solution.12.3 Designate the color of the acid layer by the number ofthe nearest matching
37、standard, following the number with aplus or minus sign if the sample is darker or lighter, respec-tively, than the standard. Disregard any difference in hue anddetermine only whether the color of the acid layer is darker orlighter than the color of the reference standard to which thesample most nea
38、rly corresponds. If the hue of the acid color isdifferent from the hue of the reference color standard, recordthe color number followed by (X). Thus “No. 4 (X)” meansthat the acid wash test color is slightly lighter than No. 4 colorstandard and that the hue of the No. 4 color standard is not thesame
39、 as the hue of the acid layer.12.4 Dispose of the acid and hydrocarbon properly beforecleaning the container. Clean the test container by flushingthoroughly with water (tap grade or better) until traces of acidhave been removed. The test container must be completely drybefore being placed back into
40、use.NOTE 5Suitable solvents, that will not impact the results, may be usedafter the water rinse step to assist in drying the container.13. Interpretation of Results13.1 Report Group 1 samples (Table 1) as passing the testonly when the oil layer shows no change in color and when theacid layer is not
41、darker than the specified color standard. Acloudiness or haze in the oil layer should not be interpreted asa change in color.13.2 When testing samples of Groups 2 or 3, disregard thecolor of the oil layer and report the sample as passing the testwhen the acid layer is not darker than the specified c
42、olorstandard.14. Precision and Bias14.1 Precision data have not been established for all types ofsamples on which this test method is used. Limited cooperativetests were conducted in 1961, principally to establish equalitywith the previously used shaking procedure. Precision esti-mates taken from th
43、ese data are as follows:Repeatability ReproducibilityAverage AcidWash ColorDegreesofFreedom95 %Repeat-abilityDegreesofFreedom95 %Repro-ducibilityBenzene 1.46.111120.751.859102.344.47Xylene 4.710.212120.401.1410101.393.5215. Keywords15.1 acid wash color; aromatic hydrocarbonsSUMMARY OF CHANGESCommitt
44、ee D16 has identified the location of selected changes to this standard since the last issue (D 848 02)that may impact the use of this issue.(1) Section 6.1 Source of bottles added to Footnote 5. (2) Section 12 Portion of Note 5 extracted and made 12.4.ASTM International takes no position respecting
45、 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 riskof infringement of such rights, are entirely their own responsibility.This standar
46、d 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 this standard or for additional standardsand should be addressed to ASTM International
47、 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.Thi
48、s 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 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).D848033
