1、Designation: D7572 11Standard Guide forRecovery of Aqueous Cyanides by Extraction from MineRock and Soil After Remediation of Process Releases1This standard is issued under the fixed designation D7572; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 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 guide is applicable for the collection, extractionand preservation of extracts fro
3、m mine rock and soil samplesfor the analysis of cyanide in the extracts. Responsibilities offield sampling personnel and the laboratory are indicated.1.2 The sampling, preservation and extraction proceduresdescribed in this practice are recommended for the analysis oftotal cyanide, available cyanide
4、, weak acid dissociable cya-nide, and free cyanide by Test Methods D2036, D4282, D4374,D6888, D6994, D7237, and D7284. The information suppliedin this practice can also be applied to other analytical methodsfor cyanide, for example, US EPA Method 335.4.1.3 The values stated in SI units are to be reg
5、arded asstandard.1.4 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-bility of regulatory limitations prior to us
6、e.2. Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD1293 Test Methods for pH of WaterD2036 Test Methods for Cyanides in WaterD3694 Practices for Preparation of Sample Containers andfor Preservation of Organic ConstituentsD3856 Guide f
7、or Good Laboratory Practices in Laborato-ries Engaged in Sampling and Analysis of WaterD4282 Test Method for Determination of Free Cyanide inWater and Wastewater by MicrodiffusionD4374 Test Methods for Cyanides in WaterAutomatedMethods for Total Cyanide, Weak Acid Dissociable Cya-nide, and Thiocyana
8、teD4840 Guide for Sample Chain-of-Custody ProceduresD4841 Practice for Estimation of Holding Time for WaterSamples Containing Organic and Inorganic ConstituentsD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisD6888 Test Method for Available Cyanide
9、 with LigandDisplacement and Flow Injection Analysis (FIA) UtilizingGas Diffusion Separation and Amperometric DetectionD6994 Test Method for Determination of Metal CyanideComplexes in Wastewater, Surface Water, Groundwaterand Drinking Water Using Anion Exchange Chromatogra-phy with UV DetectionD6696
10、 Guide for Understanding Cyanide SpeciesD7237 Test Method for Free Cyanide with Flow InjectionAnalysis (FIA) Utilizing Gas Diffusion Separation andAmperometric DetectionD7284 Test Method for Total Cyanide in Water by MicroDistillation followed by Flow Injection Analysis with GasDiffusion Separation
11、and Amperometric DetectionD7365 Practice for Sampling, Preservation and MitigatingInterferences in Water Samples for Analysis of CyanideD7511 Test Method for Total Cyanide by Segmented FlowInjection Analysis, In-Line Ultraviolet Digestion and Am-perometric Detection2.2 U.S. EPA Methods:3EPA OIA-1677
12、 Available Cyanide in WaterEPA Method 335.2 Cyanide, Total (Titrimetric; Spectropho-tometric)EPA Method 335.4 Determination of Total Cyanide bySemi-Automated Colorimetry3. Terminology3.1 Definitions: For definitions of terms used in this prac-tice, refer to Terminology D1129 and Guide D6696.1This pr
13、actice is under the jurisdiction of ASTM Committee D19 on Water andis the direct responsibility of Subcommittee D19.06 on Methods for Analysis forOrganic Substances in Water.Current edition approved May 15, 2011. Published August 2011. Last previousedition published 2009 as D757209. DOI: 10.1520/D75
14、72-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from United States Environmental Protection
15、Agency (EPA), ArielRios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460, http:/www.epa.gov.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 Definitions of Terms Specific to This Standard:3.2.1 mine rock, nore, waste rock o
16、r overburden exca-vated in order to construct an ore-processing site, or recovermetals or minerals during mining operations; or coarse pro-cessed ore such as heap-leach spoils.3.2.2 nominal size, nnin sampling, for a the opening ofthe screen of the standard series, the opening that would pass95 % of
17、 a representative sample3.2.3 refrigeration, nstoring the sample between its freez-ing point and 6C.4. Summary of Guide4.1 Samples are collected in appropriate containers at thesampling site, refrigerated and transported to the laboratorywhere they are weighed, sub-sampled, the moisture is deter-min
18、ed and cyanides are extracted prior to analysis. Results ofthe analysis of the extract are applied to the original solidsample to determine the apparent concentration of cyanidesdissolved in water present in the solids as the result of theprocess release.5. Significance and Use5.1 This practice is i
19、ntended as a means for obtaining anextract from mine rock and soil samples measure cyanideconcentrations. Cyanide is analyzed in mine rock and soilextracts for measurement of cyanide concentration; however,improper sample collection and extraction can result in signifi-cant positive or negative bias
20、, potentially resulting in unnec-essary permit violations or undetected cyanide releases into theenvironment.5.2 This practice is designed to mobilize aqueous cyanidespresent in the solids, so that the resulting extract can be used toassess leachate that could potentially be produced from reme-diate
21、d mine rock or soil in the field.5.3 This practice is not intended to simulate actual siteleaching conditions.5.4 This practice produces extracts that are amenable to thedetermination of minor (trace) constituents. When minor con-stituents are being determined, it is especially important thatprecaut
22、ions be taken in sample preservation, storage andhandling to avoid possible contamination of the extracts.5.5 This practice uses a comparative test method and isintended for use as a routine method for monitoring remediatedmine rock and soils after process releases and remediation. It isassumed that
23、 all who use this practice will be trained analystscapable of performing it skillfully and safely. It is expected thatwork will be performed in a properly equipped laboratoryapplying appropriate quality control practices such as thosedescribed in Guide D3856.6. Interferences6.1 Many interferences ar
24、e known for the analysis ofcyanide and could effect the results of the analysis of extractsproduced using this practice. Refer to Practice D7365 forproper handling of the extracts during sampling, mitigation ofinterferences and preservation prior to cyanide analysis.6.2 Unless otherwise specified, s
25、amples must be extractedwithin 72 hours and the extracts must be analyzed within 14days; however, it is recommended to estimate the actualholding time for each new sample matrix as described inPractice D4841. Certain sample matrices may require imme-diate analysis to avoid cyanide degradation due to
26、 interfer-ences. A holding time study is required if there is evidence thatcyanide degradation occurs from interferences which wouldcause the holding time to be less than specified in this practiceor Practice D7365. Potential interferences for cyanide analyti-cal methods are shown in Table 1.7. Appa
27、ratus7.1 Agitation Equipment, of any type that rotates the extrac-tion vessel in an end-over-end fashion at a rate of 30 6 2 r/minsuch that the axis of rotation is horizontal and it passes throughthe center of the bottle (see Fig. 1).7.2 Drying Pans or Dishes, for moisture content determina-tions, 5
28、00 g to 8 kg capacity.7.3 Drying OvenAny thermostatically controlled dryingoven capable of maintaining a steady temperature of 62C ina range of 100 to 110C.7.4 Extraction Vessels, cylindrical, wide-mouth, of a com-position suitable to the nature of the mine rock or soil andcyanide analyses to be per
29、formed, constructed of materials thatwill not allow sorption of the constituents of interest, andsturdy enough to withstand the impact of the falling samplefragments. The size of the container should be selected so thatthe sample, plus extraction fluid occupy approximately5095 % of the container in
30、order to provide good mixingwithout overfilling. The containers must have water-tightclosures of sufficient diameter to fill with the samples.7.5 Filtration Device, pressure or vacuum of a compositionsuitable to the nature of the analyses to be performed andequipped with a pre-washed glass wool or e
31、quivalent filter. Anassembly for pre-filtration or a centrifuge may be required iffiltration is difficult. WarningAvoid passing excessiveamounts of air through the sample during filtration to preventliberation of toxic hydrogen cyanide or cyanogen chloride gas.7.6 Laboratory Balance, capable of weig
32、hing to 1.0 g.7.7 pH Meter, with a readability of 0.01 units and anaccuracy of at least 60.1 units at 25C.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in this practice. Unless otherwise indicated, it is intendedthat all reagents shall conform to the specifications of theComm
33、ittee on Analytical Reagents of the American ChemicalSociety, where such specifications are available.4Other 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.4Reagent Chemicals, Ame
34、rican Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formular
35、y, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D7572 112TABLE 1 Examples of Potential Interferences if not Mitigated in Standard Cyanide MethodsMethod Description Measurement Interferences NumberTotalCyanideAutomatedUVColorimetric AldehydesColorFatty AcidsMercuryNitrateNitriteOxidantsSu
36、lfidesTurbiditySulfur CompoundsThiocyanateCFR Kelada-01D4374TotalCyanideManualDistillationMgCl2Amperometric AldehydesCarbonatesNitriteNitrateOxidantsSulfideSulfur CompoundsThiocyanateD7284D2036 Test Method ATotalCyanideManualDistillationMgCl2Manual orAutomatedColorimetricAldehydesCarbonatesFatty Aci
37、dsNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsThiocyanateColorTurbidityD2036 Test Method AStandard Methods 4500-CN C/E,EPA Method 335.2,EPA Method 335.4TotalCyanideManualDistillationMgCl2ISE AldehydesCarbonatesFatty AcidsNitrateNitriteOxidantsSulfideSulfur CompoundsThiocyanateColorTurbidityD2
38、036 Test Method ATotalCyanideManualDistillationMgCl2Titrimetric AldehydesCarbonatesFatty AcidsNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsThiocyanateTurbidityD2036 Test Method ATotalCyanideMicrodistillationAmperometric CarbonatesOxidantsSulfideD7284TotalCyanideUV/FIA Amperometric CarbonatesOx
39、idantsSulfideD7511AvailableCyanideFlow InjectionLigand ExchangeAmperometric CarbonatesOxidantsSulfideD6888, EPA OIA-1677D7572 113TABLE 1 ContinuedMethod Description Measurement Interferences NumberCyanideAmenable toChlorinationAlkalineChlorination andManualDistillationsManualColorimetricAldehydesCar
40、bonatesFatty AcidsNitrateNitriteOxidantsSulfideSulfur CompoundsThiocyanateColorTurbidityUnknowns that cause negative resultsD2036 Test Method BWeak AcidDissociableCyanideBufferedDistillationManualColorimetricAldehydesCarbonatesFatty AcidsNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsThiocyanate
41、TurbidityD2036 Test Method CWeak AcidDissociableCyanideAutomatedMethodAutomatedColorimetricAldehydesColorFatty AcidsMercuryNitrateNitriteOxidantsSulfidesTurbidityD4374Weak AcidDissociableCyanideBufferedDistillationISE AldehydesCarbonatesFatty AcidsNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsT
42、hiocyanateTurbidityD2036 Test Method CWeak AcidDissociableCyanideBufferedDistillationTitrimetric AldehydesCarbonatesFatty AcidsNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsThiocyanateTurbidityD2036 Test Method CWeak AcidDissociableCyanideManualColorimetricAldehydesCarbonatesFatty AcidsNitriteN
43、itrateOxidantsSugarsSulfideSulfur CompoundsThiocyanateVolatile CompoundsD2036 Test Method BD7572 114TABLE 1 ContinuedMethod Description Measurement Interferences NumberMetalCyanideComplexesIonChromatographyUV CarbonateDissolved SolidsMetal AnionsMetal CationsOxidantsPhotodecompositionD6994Free Cyani
44、de Flow Injection Amperometric CarbonateOxidantsSulfideD7237Free Cyanide Microdiffusion Colorimetric AldehydesOxidantsSulfideSulfur CompoundsD4282FIG. 1 ExtractorsD7572 1158.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water that meetsthe purity
45、 specifications of Type I or Type II water, presentedin D1193.8.3 Concentrated Sodium Hydroxide Solution (0.4 M)In a1-L volumetric flask, dissolve 16 g NaOH in reagent water anddilute to volume.8.4 Dilute Sodium Hydroxide Solution Extraction Fluid(0.04 M)In a 1-L volumetric flask, add 100 mL of 0.4
46、MNaOH in reagent water and dilute to volume.8.5 Sample BottlesSee Section 10.2 for further informa-tion about sample bottles.9. Hazards9.1 WarningBecause of the toxicity of cyanide, greatcare must be exercised in its handling. Acidification of cyanidesolutions produces toxic hydrocyanic acid (HCN).
47、Adequateventilation is necessary when handling cyanide solutions and afume hood should be utilized whenever possible.9.2 WarningMany of the reagents used in these testmethods are highly toxic. These reagents and their solutionsand extracted solids must be disposed of properly.10. Sampling10.1 Obtain
48、 a representative sample of the mine rock or soilto be tested by using, where available, ASTM samplingmethods developed for the cyanide processing industry (seePractices and ).10.2 Sampling methodology for materials of similar physi-cal form shall be used where no specific methods are available.10.3
49、 Laboratory personnel and field samplers should followthe industry best practice or acceptable metallurgical methodsfor sampling and sample preparation of mine rock.10.3.1 Fine Rock and Soil SamplingFor fine mine rockand soils, appropriate sized containers are listed in Table 2.Sampling of fine rock is recommended when reproducibleresults can be demonstrated in order to control the shippingcosts and freezing handling issues.10.3.2 Coarse Rock SamplingSamples with particle topsize in excess of 0.94 cm (38 in.) should be collected by fillinga nominal 20-L t
