1、Designation: C1234 11Standard Practice forPreparation of Oils and Oily Waste Samples by High-Pressure, High-Temperature Digestion for Trace ElementDeterminations1This standard is issued under the fixed designation C1234; the number immediately following the designation indicates the year oforiginal
2、adoption or, in the case 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.1. Scope1.1 This practice covers a high-pressure, high-temperaturedigestion tech
3、nique using the high-pressure asher (HPA) forpreparation of oils and oily waste specimens for determinationof up to 28 different elements by inductively coupled plasma-atomic emission plasma spectroscopy (ICP-AES), cold-vaporatomic absorption spectroscopy (CVAAS), and graphite fur-nace atomic absorp
4、tion spectroscopy (GFAAS), inductivelycoupled plasma-mass spectrometry (ICPMS), and radiochemi-cal methods. Oily and high-percentage organic waste streamsfrom nuclear and non-nuclear manufacturing processes can besuccessfully prepared for trace element determinations byICP-AES, CVAAS, and GFAAS. Thi
5、s practice is applicable tothe determination of total trace elements in these mixed wastes.Specimens prepared by this practice can be used to characterizeorganic mixed waste streams received by hazardous wastetreatment incinerators and for total element characterization ofthe waste streams.1.2 This
6、practice is applicable only to organic waste streamsthat contain radioactivity levels that do not require specialpersonnel or environmental protection from radioactivity orother acute hazards.1.3 A list of elements determined in oily waste streams isfound in Table 1.1.4 This practice has been used s
7、uccessfully to completelydigest a large variety of oils and oily mixed waste streams fromnuclear processing facilities. While the practice has been usedto report data on up to 28 trace elements, its success should notbe expected for all analytes in every specimen. The overallnature of these oily was
8、tes tends to be heterogeneous that canaffect the results. Homogeneity of the prepared sample iscritical to the precision and quality of the results.1.5 This practice is designed to be applicable to sampleswhose preparation practices are not defined, or not suitable, byother regulatory procedures or
9、requirements, such as the U.S.Environmental Protection Agency (EPA) SW-846 and EPA-600/4-79-020 documents. This digestion practice is designed toprovide a high level of accuracy and precision, but does notreplace or override any regulatory requirements for samplepreparation.1.6 This practice uses ha
10、zardous materials, operations, andequipment at high pressure (90110 bars, 89108 atm, or13051595 lb/in.2) and high temperatures, up to 320C, andtherefore poses significant hazards if not operated properly.1.7 The values stated in SI units are to be regarded asstandard. No other units of measurement a
11、re included in thisstandard.1.7.1 ExceptionPressure measurements are given in lb/in.units.1.8 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 practic
12、es and determine the applica-bility of regulatory limitations prior to use. Specific warningstatements are given in Sections 10.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE177 Practice for Use of the Terms Precision and Bias inASTM Test Methods2.2 US EPA Standard
13、s:3EPA-600/4-79-020 Methods for Chemical Analysis of Wa-ter and Wastes1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.03 onElemental Analysis.Current edition approved June 1, 2011. Published July
14、2011. Originally approvedin 1993. Last previous edition approved in 1998 as C 123498 which waswithdrawn June 2009 and reinstated in June 2011. DOI: 10.1520/C123411.2For referenced ASTM Standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. ForAnnual Book
15、 of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.1Copyright ASTM International, 100
16、Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.SW-846 Test Methods for Evaluating Solid Waste, Physical/Chemical Methods3. Terminology3.1 Definitions:3.1.1 heating block, naluminum block used to holdsamples inside the HPA autoclave/pressure chamber.3.1.2 HPA-TC contr
17、oller, ncomputer interface betweenHPA autoclave and an IBM-compatible computer.3.1.3 pressure chamber, nchamber within the HPA auto-clave where heating block filled with samples is placed. Thechamber is designed to hold pressures up to 200 bar (197 atmor 2900 lb/in.2) and temperatures up to 320C.3.1
18、.4 safety lid vent stack, ntop plate and cylinder thatcovers the autoclave pressure chamber.3.1.5 sample vessel, nsample container, constructed ofquartz or glassy carbon, designed for use in the HPA.3.1.6 temperature program, nsoftware program whichcontrols the temperature ramping of the HPA during
19、the run.The program used for preparation of oil samples is shown inTable 2.4. Summary of the Practice4.1 Oil or oily waste specimens are digested in nitric andhydrochloric acids using HPA high-pressure, high-temperatureequipment. Prepared specimens of 0.2 to 0.7 g will provideenough solution for ana
20、lysis by CVAAS, ICP-AES, andGFAAS for up to 28 elements.5. Significance and Use5.1 This practice is useful for preparation of difficult-to-digest, primarily oils and oily wastes, specimens for traceelement determinations of up to 28 elements by atomicabsorption or plasma emission techniques. Specime
21、n prepara-tion by high-pressure ashing is primarily applicable to speci-mens whose preparation by EPASW-846 protocols is either notapplicable or not defined. This sample preparation practice isapplicable for the trace element characterization of mixed oilywastes for use by waste treatment facilities
22、 such as incineratorsor waste stabilization facilities.6. Interferences6.1 Preparation of samples for trace element determinationsis subject to matrix and chemical interferences. Although theHPA practice is designed to totally digest most matrices, thereare some matrix types that are not applicable
23、to this practice,for example, highly reactive substances (explosives), ex-tremely flammable materials, and some silicone-based lubri-cants.7. Apparatus7.1 HPA High Pressure Asher4High-pressure, high-temperature autoclave under computer control allowing com-plete digestion of difficult specimens usin
24、g mineral acids. Thesystem includes:7.1.1 Compatible computer with hard drive and with oneopen RS-232C serial interface.7.1.2 HPA-TC temperature controllerthis device providesthe interface between the HPA autoclave and the computer bymeans of RS-232C serial interface.7.1.3 HPA autoclave unit.7.1.4 H
25、PA sample vessels, appropriate size and constructionfor specimen type and mineral acid used.7.2 Ultrasonic HomogenizerSpecimen homogenizer us-ing ultrasonic disruption tip to homogenize specimens thatcannot be mixed by hand.8. Reagents and Materials8.1 Purity of ReagentsChemicals used in the prepara
26、tionof spiking standards must be of ultra purity grade. Chemicalsand reagents used in the preparation practice must conform tothe specifications of the Committee on Analytical Reagents of4The sole source of supply of the apparatus known to the committee at this timeis Anton Paar K. G., Graz, Austria
27、. If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful consideration at a meeting of the responsible technical committee,1which you may attend.TABLE 1 List of Elements and Applicable Lower ConcentrationRangesE
28、lementLower ReportableLimit,Ag/gAnalysis MethodAluminum 3.3 ICP-AESAntimony 8.3 ICP-AES or GFAASArsenic 8.3 ICP-AES or GFAASBarium 0.17 ICP-AESBeryllium 0.05 ICP-AESBoron 0.67 ICP-AESCadmium 0.50 ICP-AES or GFAASCalcium 0.67 ICP-AESChromium 1.7 ICP-AESCobalt 0.83 ICP-AESCopper 0.67 ICP-AESIron 0.67
29、ICP-AESLead 8.3 ICP-AES or GFAASLithium 0.67 ICP-AESMagnesium 0.08 ICP-AESManganese 0.17 ICP-AESMercury 0.03 CVAASNickel 1.7 ICP-AESPotassium 100 ICP-AESSelenium 8.3 ICP-AES or GFAASSilver 1.0 ICP-AESSodium 3.3 ICP-AESStrontium 0.07 ICP-AESThallium 1.7 GFAASTitanium 0.50 ICP-AESVanadium 0.83 ICP-AES
30、Zinc 0.17 ICP-AESZirconium 0.83 ICP-AESALower reportable limits are based on a 0.3-g sample diluted to a final volumeof 50 mL. These limits should only be used as a guide. Actual values areinstrument and sample dependent.TABLE 2 HPA Temperature Program for Oils and Oily WasteSamplesPhaseStartingTemp
31、erature,CTime, minEndingTemperature,C1 100 30 1252 125 60 3003 300 60 300425302550 0C1234 112the American Chemical Society, where such specifications areavailable.5Other grades may be used, provided it is firstascertained that the reagent is of sufficient purity to permit itsuse without lessening th
32、e accuracy of the determination.8.2 Reagent WaterReferences to water shall be under-stood to mean reagent water as defined by Type 1 of Specifi-cation D1193.8.3 Nitric Acid (sp gr 1.42)Ultra pure concentrated nitricacid (HNO3).8.4 Hydrochloric Acid (sp gr 1.19)Ultra pure concen-trated hydrochloric a
33、cid (HCl).8.5 Hydrofluoric Acid (sp gr 0.988)Ultra pure concen-trated hydrofluoric acid (HF).8.6 Matrix Spiking StandardsMultielement standardsused for matrix spiking shall be of sufficient purity andaccuracy and, where possible, traceable to accepted nationallyknown standards (that is, National Ins
34、titute of Standards andTechnology (NIST) or EPA). Spiking standards used shouldyield spiked specimens with concentrations between 0.5 to 2mg/L for most elements.9. Sample Preparation9.1 Homogeneous specimens are a requirement if suitableanalytical precision is expected. Most oils and oily wastesrequ
35、ire additional steps to provide homogeneous specimens forpreparation. If the sample is visibly clear or can be shaken toprovide a homogeneous specimen, no further pretreatment isnecessary.9.2 Liquid or aqueous specimens that are cloudy or containvisible sediment or precipitates may require an ultras
36、onic bathto resuspend settled material or maintain a homogeneousspecimen for preparation. The process of ultrasonic mixingwill generate heat, and warm the sample above ambienttemperature. A consideration of the original sample must bemade as to the effect of ultrasonification on the sample. Asample
37、with a low boiling point, such as freon, may not beapplicable to ultrasonic mixing. Ultrasonification between 1 to5 min is effective for liquid or aqueous samples.9.3 It is difficult to obtain homogeneous specimens forpreparation from multi-phase liquids, oils, oily wastes, orsamples with large amou
38、nts of solid matter. For these sampletypes, an ultrasonic sonifier is very useful in providing ahomogeneous specimen. The sonifier uses high-frequencyelectrical energy transmitted through a converter to vibrate ametal horn tip that is immersed in the sample. The vibration ofthe horn tip causes cavit
39、ation of medium that causes the intenseagitation of the medium leading to very stable emulsions to beformed, even between polar and non-polar liquids.9.3.1 The sonification process will generate heat, and thespecimen should be checked during the process. Specimenhomogenization is determined by visua
40、l observation and isnormally complete within 10 to 60 s. If heat generation in thesample becomes a problem, determined by the temperature risein the specimen, then the homogenization should be judgedcomplete when the sample temperature rises to this level, asdetermined on a specimen by specimen basi
41、s. Process andobserve each sample individually to obtain the best, mostrepresentative results. Specimens with low flash points are notrecommended for homogenization by this method.9.3.2 Process the specimen immediately to maintain itshomogeneity.10. Procedure10.1 Weigh 0.2 to 0.7 g of homogeneous sa
42、mple into a cleanHPA vessel. The sample mass necessary for the HPA is matrixdependent, that is, organic or inorganic content, and samples upto 2 g can be prepared. Sample sizes of 0.2 to 0.7 g aresuccessful for highly organic specimens. The organic compo-nent of the specimen will have a direct effec
43、t on the digestionin the HPA; the more organic a specimen the more internalpressure may be generated. Due to the closed vessel HPAtechnique, the possibility of a specimen venting during theHPA digestion is proportional to its mass.10.2 Within a preparation batch, with the number of speci-mens define
44、d by the laboratory, the following quality controlsamples should be included; a reagent blank containing allreagents used in the procedure, a matrix duplicate specimen forassessing precision, and a matrix spiked specimen for assessingmethod accuracy. A batch size of ten specimens has beensuccessful
45、for HPAdigestion performed on oily waste samples.10.3 Exercise extreme caution when handling specimensduring the pressure decomposition process, as spontaneousviolent reactions may occur under adverse conditions. Thesafety design features of the HPA equipment allow for sampleexplosive reactions to o
46、ccur inside the pressure chamberwithout adverse effects on the equipment or its operators. Atantalum rupture disk will blow out to relieve the pressure if theinternal pressure of the sealed chamber should rise above 200bars (197 atm or 2900 lb/in.2). (WarningAdequate labora-tory facilities, such as
47、fume hoods and controlled ventilation,along with normal safe laboratory techniques, must be used inthis procedure. Due to the rupture disk feature, the HPAequipment should always be operated in a fume hood.)10.4 Place sample vessels in the fume hood and add 5 mLconcentrated HNO3and 2.5 mL HCl. The i
48、nclusion of HCl isnecessary to solubilize any iron oxyhydroxides which may bepresent in the specimen or digestate and to yield quantitativerecovery of silver and antimony.10.4.1 Hydrofluoric acid should be used if siliceous mate-rials are being prepared and must be used only in glassy carbonvessels.
49、 (WarningDue to the tendency of hydrofluoric acidto cause severe skin and tissue damage, extreme caution mustbe exercised when HF is used or may be present.)10.5 Place a layer of 1 in. polytetrafluoroethylene (PTFE)tape over the top of the sample vessel. Check to be sure thesurface is smooth and free of ripples. Pierce the tape in thecenter to provide for pressure equilibration.NOTE 1Refer to manufacturers operating manual for high pressureAsher vessel details.5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washing
