1、Designation: D874 13a British Standard 4716Standard Test Method forSulfated Ash from Lubricating Oils and Additives1This standard is issued under the fixed designation D874; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method covers the deter
3、mination of the sul-fated ash from unused lubricating oils containing additives andfrom additive concentrates used in compounding. These addi-tives usually contain one or more of the following metals:barium, calcium, magnesium, zinc, potassium, sodium, and tin.The elements sulfur, phosphorus, and ch
4、lorine can also bepresent in combined form.1.2 Application of this test method to sulfated ash levelsbelow 0.02 mass % is restricted to oils containing ashlessadditives. The lower limit of the test method is 0.005 mass %sulfated ash.NOTE 1This test method is not intended for the analysis of usedengi
5、ne oils or oils containing lead. Neither is it recommended for theanalysis of nonadditive lubricating oils, for which Test Method D482 canbe used.NOTE 2There is evidence that magnesium does not react the same asother alkali metals in this test. If magnesium additives are present, the datais interpre
6、ted with caution.NOTE 3There is evidence that samples containing molybdenum cangive low results because molybdenum compounds are not fully recoveredat the temperature of ashing.1.3 Fatty acid methyl ester (FAME) conforming to EN14213 and EN 14214, when tested using this test method, wereshown to mee
7、t its precision.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 concerns, if any, associated with its use. It is theresponsibility of the user of this standard t
8、o establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D482 Test Method for Ash from Petroleum ProductsD1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum
9、 andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System Performance2.2 CEN Standards:3EN 14213 Heating FuelsFatty Acid Methyl Esters
10、(FAME)Requirements and Test MethodsEN 14214 Automotive FuelsFatty Acid Methyl Esters(FAME) for Diesel EnginesRequirements and TestMethods3. Terminology3.1 Definitions:3.1.1 sulfated ashthe residue remaining after the samplehas been carbonized, and the residue subsequently treated withsulfuric acid a
11、nd heated to constant weight.4. Summary of Test Method4.1 The sample is ignited and burned until only ash andcarbon remain. After cooling, the residue is treated withsulfuric acid and heated at 775C until oxidation of carbon iscomplete. The ash is then cooled, re-treated with sulfuric acid,and heate
12、d at 775C to constant weight.5. Significance and Use5.1 The sulfated ash can be used to indicate the concentra-tion of known metal-containing additives in new oils. Whenphosphorus is absent, barium, calcium, magnesium, sodium1This test method is under the jurisdiction of ASTM Committee D02 onPetrole
13、um Products and Lubricants and is the direct responsibility of SubcommitteeD02.03 on Elemental Analysis.Current edition approved Sept. 1, 2013. Published September 2013. Originallyapproved in 1946. Last previous edition approved in 2013 as D874 13. DOI:10.1520/D0874-13A.In the IP, this test method i
14、s under the jurisdiction of the StandardizationCommittee. This test method has been approved by the sponsoring committees andaccepted by the cooperating societies in accordance with established procedures.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer S
15、ervice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from European Committee for Standardization (CEN-CENELECManagement Centre), Avenue Marnix 17, B-1000, Brussels, Belgium, http:/www.cenorm.be.*A S
16、ummary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1and potassium are converted to their sulfates and tin (stannic)and zinc to their oxides (Note 4). Sulfur and chlorine do noti
17、nterfere, but when phosphorus is present with metals, itremains partially or wholly in the sulfated ash as metalphosphates.NOTE 4Since zinc sulfate slowly decomposes to its oxide at theignition temperature specified in the test method, samples containing zinccan give variable results unless the zinc
18、 sulfate is completely converted tothe oxide.5.2 Because of above inter-element interferences, experi-mentally obtained sulfated ash values may differ from sulfatedash values calculated from elemental analysis. The formationof such non-sulfated species is dependent on the temperature ofashing, time
19、ashed, and the composition of metal compoundspresent in oils. Hence, sulfated ash requirement generallyshould not be used in product specifications without a clearunderstanding between a buyer and a seller of the unreliabilityof an ash value as an indicator of the total metallic compoundcontent.46.
20、Apparatus6.1 Evaporating Dish or Crucible; 50 to 100-mL forsamples containing more than 0.02 mass % sulfated ash, or 120to 150-mL for samples containing less than 0.02 mass %sulfated ash, and made of porcelain, fused silica, or platinum.( WarningDo not use platinum when the sample is likely tocontai
21、n elements such as phosphorus, which attack platinumunder the conditions of the test.)NOTE 5For best results on samples containing less than 0.1 mass %sulfated ash, platinum dishes are used. The precision values shown inSection 13 for this type of sample were so obtained.6.2 Electric Muffle FurnaceT
22、he furnace shall be capableof maintaining a temperature of 775 6 25C and preferablyhave apertures at the front and rear to allow a slow natural draftof air to pass through the furnace.6.3 Balance, capable of weighing to 0.1 mg.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in
23、all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available, or to other recognizedstandards for reagent chemicals.5Other grades may be use
24、d,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water defined byTypes II or III of Specificatio
25、n D1193.7.3 Low-Ash Mineral OilWhite oil having a sulfated ashlower than the limit capable of being determined by this testmethod.NOTE 6Determine the sulfated ash of this oil by the procedure givenin 9.1-9.11 below using 100 g of white oil weighed to the nearest 0.5 g ina 120 to 150-mL platinum dish
26、. Deduct the sulfuric acid blank asdescribed in 9.11.7.4 Sulfuric Acid (relative density 1.84)Concentrated sul-furic acid (H2SO4). ( WarningPoison. Corrosive. Strongoxidizer.)7.5 Sulfuric Acid (1 + 1)Prepare by slowly adding 1volume of concentrated sulfuric acid (relative density 1.84) to1 volume of
27、 water with vigorous stirring. ( WarningMixingthis acid into water generates considerable heat. Whennecessary, cool the solution before adding more acid. Do notallow the solution to boil.)7.6 Propan-2-ol, (WarningFlammable, can be explosivewhen evaporated to or near dryness.) 99 % minimum purity.7.7
28、 Toluene, (WarningFlammable, toxic.) 99 % mini-mum purity.7.8 Quality Control (QC) Samples , preferably are portionsof one or more liquid petroleum materials that are stable andrepresentative of the samples of interest. These QC samplescan be used to check the validity of the testing process asdescr
29、ibed in Section 12.8. Sampling8.1 Obtain samples in accordance with the instructions inPractice D4057 or D4177. The sample shall be thoroughlymixed before removal of the laboratory test portion.9. Procedure9.1 Select the size of the evaporating dish or crucibleaccording to the quantity of sample nec
30、essary (see 9.3).9.2 Heat the evaporating dish or crucible that is used for thetest at 775 6 25C for a minimum of 10 min. Cool to roomtemperature in a suitable container and weigh to the nearest 0.1mg.NOTE 7The container in which the dish is cooled does not contain adesiccating agent.9.3 Weigh into
31、the dish a quantity of sample given asfollows:W 5 10/a (1)where:W = mass of test specimen, g, anda = expected sulfated ash, mass %.However, do not take a quantity in excess of 80 g. In the caseof lubricating oil additives yielding a sulfated ash of 2 mass %or more, dilute the weighed sample in the d
32、ish with approxi-mately 10 times its weight of low-ash mineral oil. If theamount of sulfated ash found differs from the expected amountby more than a factor of two, repeat the analysis with a4Further discussion of these interferences can be found in Nadkarni, R. A.,Ledesma, R. R., and Via, G. H., “S
33、ulfated Ash TM: Limitations of Reliability andReproducibility,” SAE Technical Paper No. 952548, available from SAE, 400Commonwealth Drive, Warrendale, PA 15096-0001, U.S.A.5Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the
34、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.D874 13a2different weight of sample calculat
35、ed from the first analysisunless the calculated sample size 80 g.9.4 Heat the dish or crucible and sample carefully until thecontents can be ignited with a flame. Maintain at such atemperature that the sample continues to burn at a uniform andmoderate rate. When burning ceases, continue to heat gent
36、lyuntil no further smoke or fumes are evolved.9.4.1 If the sample contains sufficient moisture to causefoaming and loss of material from the dish, discard the sampleand to an additional sample add 1 to 2 mL of 99 % propan-2-ol(Warning Flammable) before heating. If this is notsatisfactory, add 10 mL
37、of a mixture of equal volumes oftoluene (Warning Flammable, Vapor harmful.) and propan-2-ol and mix thoroughly. Place several strips of ashless filterpaper in the mixture and heat; when the paper begins to burn,the greater part of the water will have been removed.9.5 Allow the dish to cool to room t
38、emperature, thencompletely moisten the residue by the dropwise addition ofsulfuric acid (relative density 1.84). Carefully heat the dish ata low temperature on a hot plate or over a gas burner, avoidingspattering, and continue heating until fumes are no longerevolved.9.6 Place the dish in the furnac
39、e at 775 6 25C for 30 6 5min until oxidation of the carbon is complete or almostcomplete.9.7 Allow the dish to cool to room temperature.Add 3 dropsof water and 10 drops of sulfuric acid (1 + 1). Move the dish soas to moisten the entire residue. Again heat the dish inaccordance with 9.5.9.8 Again pla
40、ce the dish in the furnace at 775 6 25C andmaintain at that temperature for 30 6 5min (see Note 8). Coolthe dish to room temperature in a suitable container (see Note7). Zinc dialkyl or alkaryl dithiophosphates and blends con-taining these additives can give a residue that is partially blackat this
41、stage. In this case, repeat 9.7 and 9.8 until a whiteresidue is obtained.NOTE 8A study conducted by two separate laboratories investigatingwhether heating sulfated ash residues for extended periods of time (forexample, overnight) in a furnace at 775 6 25C as opposed to 30 min asrequired in 9.8 revea
42、led that a significant difference in sulfated ash resultscan exist. The study indicated that lower sulfated ash results were obtainedon the samples left in the furnace overnight versus those that were heatedin 30min cycles. A thermogravimetric analysis also confirmed that thesamples evaluated contin
43、ued to lose weight at 775C as a function of time.As such, it is essential that the 30min heating time requirement beadhered to in performing the test method. Details concerning the study canbe found in ASTM Research Report RR:D02-1597.9.9 Weigh the dish and residue to the nearest 0.1 mg.9.10 Repeat
44、9.8 and 9.9 until two successive weighingsdiffer by no more than 1.0 mg.NOTE 9Normally one repeat will suffice, unless a high proportion ofzinc is present, when three or four heating periods can be required.9.11 For samples expected to contain 0.02 mass % or less ofsulfated ash, determine a sulfuric
45、 acid blank by adding 1 mL ofthe concentrated sulfuric acid to a tared platinum dish orcrucible, heating until fumes are no longer evolved and thenheating in the furnace at 775 6 25C for 30 6 5 min. Cool thedish or crucible to room temperature in a suitable container(see Note 7) and weigh to the nea
46、rest 0.1 mg. If any ash isfound in the sulfuric acid, make an adjustment to the weight ofsulfated ash obtained by subtracting the weight of ash contrib-uted by the sulfuric acid, determined from the total volume ofsulfuric acid used and the weight of ash found for the 1-mLblank, from the total grams
47、 of sulfated ash for the sample. Usethis corrected weight, w, in calculating the percent sulfated ash.10. Calculation10.1 Calculate the sulfated ash as a percentage of theoriginal sample as follows:Sulfated ash, mass% 5 w/W! 3100 (2)where:w = grams of sulfated ash, andW = grams of sample used.11. Re
48、port11.1 Report the result to the nearest 0.001 mass % forsamples below 0.02 mass % and to the nearest 0.01 mass % forhigher levels as the sulfated ash, Test Method D874.12. Quality Control12.1 Confirm the performance of the instrument or the testprocedure by analyzing a QC sample (see 7.8).12.1.1 W
49、hen QC/Quality Assurance (QA) protocols arealready established in the testing facility, these may be used toconfirm the reliability of the test result.12.1.2 When there is no QC/QA protocol established in thetesting facility, Appendix X1 can be used as the QC/QAsystem.13. Precision and Bias613.1 The precision of this test method as determined bystatistical examination of interlaboratory results is as follows:13.1.1 For sulfated ash levels between 0.005 and 0.10mass %.13.1.1.1 RepeatabilityThe difference between two testresults obtained by the
