1、Designation: D 4625 04 (Reapproved 2009)Designation: 378/87Standard Test Method forMiddle Distillate Fuel Storage Stability at 43C (110F)1This standard is issued under the fixed designation D 4625; the number immediately following the designation indicates the year oforiginal adoption or, in the cas
2、e of revision, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test
3、method covers a method for evaluating theinherent storage stability of distillate fuels having flash pointsabove 38C (100F), by Test Methods D93, and 90 % distilledpoints below 340C (644F), by Test Method D86.NOTE 1ASTM specification fuels falling within the scope of this testmethod are Specificatio
4、n D 396, Grade Nos. 1 and 2; Specification D 975,Grades 1-D and 2-D; and Specification D 2880, Grades 1-GT and 2-GT.1.2 This test method is not suitable for quality controltesting but, rather it is intended for research use to shortenstorage time relative to that required at ambient storagetemperatu
5、res.1.3 Appendix X1 presents additional information aboutstorage stability and the correlation of Test Method D 4625results with sediment formation in actual field storage.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibilit
6、y of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D86 Test Method for Distillation of Petroleum Products atAtmospheric PressureD93 Test Methods for Fl
7、ash Point by Pensky-MartensClosed Cup TesterD 381 Test Method for Gum Content in Fuels by JetEvaporationD 396 Specification for Fuel OilsD 975 Specification for Diesel Fuel OilsD 1193 Specification for Reagent WaterD 2880 Specification for Gas Turbine Fuel OilsD 4057 Practice for Manual Sampling of
8、Petroleum andPetroleum ProductsD 4177 Practice for Automatic Sampling of Petroleum andPetroleum Products3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 adherent insolubles, ngums formed during storagethat remain tightly attached to the walls of the vessel.3.1.2 filterable inso
9、lubles, nsolids formed during storagethat can be removed from the fuel by filtration.3.1.3 inherent storage stability, nof middle distillatefuelthe resistance to change in storage in contact with air, butin the absence of other environmental factors such as water, orreactive metallic surfaces and di
10、rt.3.1.4 total insolubles, nsum of the filterable insolublesplus the adherent insolubles.4. Summary of Test Method4.1 Four-hundred millilitre volumes of filtered fuel are agedby storage in borosilicate glass containers at 43C (110F) forperiods of 0, 4, 8, 12, 18, and 24 weeks. After aging for aselec
11、ted time period, a sample is removed from storage, cooledto room temperature, and analyzed for filterable insolubles andfor adherent insolubles.5. Significance and Use5.1 Fuel oxidation and other degradative reactions leadingto formation of sediment (and color) are mildly accelerated bythe test cond
12、itions compared with typical storage conditions.Test results have been shown to predict storage stability more1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.14 on Stability and Cleanliness of L
13、iquid Fuels.Current edition approved June 1, 2009. Published August 2009. Originallyapproved in 1986. Last previous edition approved in 2004 as D 462504.This test method was adopted as a joint ASTM/IP standard in 1986.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS
14、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.reliably than other more acc
15、elerated tests. SeeAppendix X1 forinformation on the correlation of test results with actual fieldstorage.5.2 Because the storage periods are long (4 to 24 weeks), thetest method is not suitable for quality control testing, but doesprovide a tool for research on storage properties of fuels.5.3 Becau
16、se environmental effects and the materials andnature of tank construction affect storage stability, the resultsobtained by this test are not necessarily the same as thoseobtained during storage in a specific field storage situation.6. Apparatus6.1 Sample Containers, borosilicate glass bottles. The c
17、on-tainers must have a lid or cover, preferably with a polytet-rafluoroethylene (PTFE) insert and a hole for a borosilicateglass vent. The total capacity of the containers is 500 mL.6.2 Storage Oven, large enough to contain all of the samplebottles. The oven shall be thermostatically controlled to m
18、ain-tain a temperature of 43 6 1C (110 6 2F). It shall be as darkas possible to prevent degradation due to photolytic reactionsand shall also be explosion proof.6.3 Filter Drying Oven, shall be capable of safely evapo-rating the solvent at 90 6 5C for the drying of filter materials.6.4 Filtration Sy
19、stemArrange the following componentsas shown in Fig. 1.6.4.1 Funnel and Funnel Base, with filter support for a47-mm diameter membrane and a locking ring or spring actionclip.6.4.2 Ground/Bond Wire, 0.9122.59 mm (No. 10No. 19)bare-stranded, flexible stainless steel or copper installed in theflasks an
20、d grounded as shown in Fig. 1.6.4.3 Receiving Flask, 1.5 L or larger borosilicate glassvacuum filter flask, which the filtration apparatus fits into,equipped with a sidearm to connect to the safety flask.6.4.4 Safety Flask, 1.5 L or larger borosilicate glass vacuumfilter flask equipped with a sidear
21、m to connect the vacuumsystem. A fuel and solvent resistance rubber hose, throughwhich the grounding wire passes, shall connect the sidearm ofthe receiving flask to the tube passing through the rubberstopper in the top of the safety flask.6.4.5 Vacuum System, either a water-aspirated or a mechani-ca
22、l vacuum pump may be used if capable of producing avacuum of up to 100 kPa below atmospheric pressure whenmeasured at the receiving flask.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conf
23、orm to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.3Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe de
24、termination.7.2 Nylon Test and Control Membrane Filtersplain,47-mm diameter, nominal pore size 0.8-m. (Membrane filterswith a grid imprinted on their surface may be used as controlmembrane filters for identification.)7.3 Hydrocarbon Solvent, 2,2,4-trimethylpentane (iso-octane)ASTM knock test referen
25、ce fuel grade, prefilteredthrough two glass-fiber filters. (WarningExtremely flam-mable. Harmful if inhaled. Vapors may cause flash fire.)7.4 Adherent Insolubles Solvent (WarningExtremelyflammable. Vapors harmful. May cause flash fire)Mix equalvolumes of reagent grade acetone (WarningExtremely flam-
26、mable. Vapors may cause flash fire), methyl alcohol(WarningFlammable. Vapor harmful. May be fatal or causeblindness if swallowed or inhaled. Cannot be made nonpoison-ous), and toluene (WarningFlammable. Vapor harmful.).7.5 Purity of WaterUnless otherwise indicated, referencesto water mean reagent wa
27、ter as defined by Type III ofSpecification D 1193.7.6 Liquid or Powder Detergent, water-soluble, for cleaningglassware.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical
28、 Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.FIG. 1 Schematic of Filtration SystemD 4625 04 (2009)28. Sampling Procedure8.1 Samples for testing
29、 shall be obtained by an appropriatemethod outlined in Practice D 4057 or D 4177. Sample con-tainers should be 1 gal (3.78 L) or larger, epoxy-lined cans. Fillsample cans almost to the top to avoid a significant air space.Purge the void space with nitrogen. Store the samples atreduced temperature, -
30、7 to 4C (20 to 40F), prior to use, wherepossible.9. Preparation of Apparatus and Sample Bottles9.1 Sample Storage BottlesScrub each bottle with a de-tergent solution and rinse it with water. Soak the bottleovernight in a mildly alkaline laboratory glassware cleaningsolution. Rinse the bottle with ta
31、p water, then invert it and flushit with a stream of distilled water. Allow the bottles to dry andrinse the bottles with 50 mL of the fuel sample. Vent the bottlesduring storage, using a glass tube bent in an upside down “U,”(see Fig. 2), to prevent contamination of the sample fromairborne particula
32、tes. Insert the glass tube through a cover,preferably equipped with a polytetrafluoroethylene (PTFE)insert (see Fig. 2).9.2 Clean all components of the filtration apparatus asdescribed in 9.2.1-9.2.7.9.2.1 Remove any labels, tags, and so forth.9.2.2 Wash with warm tap water containing detergent.9.2.
33、3 Rinse thoroughly with warm tap water.9.2.4 Rinse thoroughly with deionized water. Containercaps should be handled only externally with clean laboratorycrucible tongs during this and subsequent washings.9.2.5 Rinse thoroughly with propan-2-ol that has beenfiltered through a 0.45-m membrane filter.9
34、.2.6 Rinse thoroughly with filtered flushing fluid and dry.9.2.7 Keep a clean protective cover (the cover may be rinsedwith filtered flushing fluid) over the top of the sample containeruntil the cap is installed. Similarly, protect the funnel openingof the assembled filtration apparatus with a clean
35、 protectivecover until ready for use.9.3 Preparation of Membrane Filters:9.3.1 Each set of test filters consists of one test membranefilter and one control membrane filter. For fuels containinglittle particulate materials, only one set of filters is required. Ifthe fuel is highly contaminated, more
36、than one set of filtersmay be required. The two membrane filters used for eachindividual test shall be identified by marking the petri dishesused to hold and transport the filters. Clean all glassware usedin preparation of membrane filters as described in 9.2.9.3.1.1 Using forceps, place the test an
37、d control membranefilters side by side in a clean petri dish. To facilitate handling,the membrane filters should rest on clean glass support rods, orwatch glasses, in the petri dish.9.3.1.2 Place the petri dish, with its lid slightly ajar, in adrying oven at 90 6 5C and leave it for 30 min.9.3.1.3 R
38、emove the petri dish from the drying oven, andplace it near the balance. Keep the petri dish cover ajar, butkeep it such that the membrane filters are still protected fromcontamination from the atmosphere. Allow 30 min for themembrane filters to come to equilibrium with room air tem-perature and hum
39、idity.9.3.1.4 Remove the control membrane filter from the petridish with forceps, handling by the edge only, and place itcentrally on the weighing pan of the balance. Weigh it, recordthe initial mass to the nearest 0.0001 g, and return it to the petridish.9.3.1.5 Repeat 9.3.1.4 for the test membrane
40、 filter.9.3.1.6 Using clean forceps, place the weighed controlmembrane filter centrally on the membrane filter support of thefiltration apparatus (see Fig. 1). Place the weighed test mem-brane filter on top of the control membrane filter. Install thefunnel and secure with locking ring or spring clip
41、. Do notremove the plastic film from the funnel opening until ready tostart filtration.10. Preparation of Sample10.1 If the fuel has been stored at reduced temperature,allow the sample to come to ambient temperature. To dissolveany separated wax, be certain that the entire fuel sample is atleast 5C
42、above its cloud point before proceeding.10.2 Assemble a filtration system, as shown in Fig. 1,tofilter the fuel. Clean the receiving flask, separatory funnel, andglass funnel in the same manner as the storage bottles (9.1).Rinse these items with filtered isooctane and then air.11. Procedure11.1 Samp
43、le Aging:11.1.1 Adjust the storage oven for sample storage to atemperature of 43 6 1C (110 6 2F).11.1.2 Place 400 mL of filtered fuel into each bottle. Usetwo bottles for each sampling period. (Commonly used sam-pling periods are 0, or any of the following: 4, 8, 12, and 24weeks). Fill three extra b
44、ottles with fuel to be used in case ofaccidents, for further tests at other times of storage, or toextend the overall test duration.11.1.3 Label each storage bottle with the time and date thetest is started, sample identification, and the time and dateFIG. 2 Sample Storage ContainerD 4625 04 (2009)3
45、when the bottle is to be removed from storage. Place the bottlesin the oven in random order.11.1.4 Perform zero-week analyses on the same day as theother samples are placed in storage. Zero-week data arenecessary to provide base data and assure satisfactory tech-nique.11.2 Determination of Filterabl
46、e Insolubles:11.2.1 At the end of each prescribed period of time, removetwo bottles from the storage oven and allow them to cool to 21to 27C (70 to 80F) in a dark environment. This may takefrom4to24h.11.2.2 After cooling, pour fuel from the sample container tothe graduated cylinder, start the vacuum
47、, and then transfer 100mL of fuel to the filter funnel.11.2.2.1 Continue transferring 100-mL increments of fuel tothe filter funnel. When all the fuel from the sample containerhas been filtered, or if filtration slows so that 100 mL of samplerequires greater than 10 min for complete filtration, then
48、remove the filter support/filter funnel from the receiving flask,pour the filtered fuel into a clean graduated cylinder, and recordthe volume of fuel that was filtered in millilitres. Keep the fuelsample filtrate separate from the solvent washings filtrate. Thisallows the fuel to be used for additio
49、nal analyses. If all the fuelhas been filtered, thoroughly rinse the sample container and thegraduated cylinder with one or more portions of filteredflushing fluid, pour the rinses into the funnel, and proceed to11.2.2.2. If all the fuel has not been filtered, proceed to 11.2.2.2and 11.2.2.3, and then repeat from 11.2.2.1.11.2.2.2 Wash down the inside of the funnel and the outsideof the joint between the funnel and filter base filtered withflushing fluid. With the vacuum applied, carefully separate thefunnel from the filter base. Wash the pe
