1、Designation: D7572 13D7572 15Standard Guide forRecovery of Aqueous Cyanides by Extraction from MineRock and Soil1This standard is issued under the fixed designation D7572; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、 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. Scope*1.1 This guide is applicable for the collection, extraction, and preservation of extracts from mine rock and soil sample
3、s for theanalysis of cyanide in the extracts. Responsibilities of field sampling personnel and the laboratory are indicated.1.2 The sampling, preservation, and extraction procedures described in this guide are recommended for the analysis of totalcyanide, available cyanide, weak acid dissociable cya
4、nide, and free cyanide by Test Methods D2036, D4282, D4374, D6888,D6994, D7237, and D7284. The information supplied in this guide can also be applied to other analytical methods for cyanide,for example, US EPA Method 335.4.1.3 The procedure options methods appear in the following order:Procedure Opt
5、ion SectionsOption ALaboratory Processing of FieldPreserved Samples11 and 12Option BLaboratory Processing of MoistField Samples13 and 141.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to
6、address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1129 Termin
7、ology 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 and for Preservation of Organic ConstituentsD3856 Guide for Management Systems in Laboratories Engaged in Analysi
8、s of WaterD4282 Test Method for Determination of Free Cyanide in Water and Wastewater by MicrodiffusionD4374 Test Methods for Cyanides in WaterAutomated Methods for Total Cyanide, Weak Acid Dissociable Cyanide, andThiocyanate (Withdrawn 2012)3D4840 Guide for Sample Chain-of-Custody ProceduresD4841 P
9、ractice for Estimation of Holding Time for Water Samples Containing Organic and Inorganic ConstituentsD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water AnalysisD6696 Guide for Understanding Cyanide Species1 This guide is under the jurisdiction of ASTM Comm
10、ittee D19 on Water and is the direct responsibility of Subcommittee D19.06 on Methods for Analysis for OrganicSubstances in Water.Current edition approved June 1, 2013Feb. 1, 2015. Published July 2013February 2015. Originally approved in 2009. Last previous edition published 20112013 as D7572 11a.13
11、. DOI: 10.1520/D7572-13.10.1520/D7572-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved
12、version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict al
13、l changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 1
14、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D6888 Test Method forAvailable Cyanide with Ligand Displacement and Flow InjectionAnalysis (FIA) Utilizing Gas DiffusionSeparation and Amperometric DetectionD6994 Test Method for Determination of Metal Cyanide Complex
15、es in Wastewater, Surface Water, Groundwater and DrinkingWater Using Anion Exchange Chromatography with UV DetectionD7237 Test Method for Free Cyanide with Flow InjectionAnalysis (FIA) Utilizing Gas Diffusion Separation andAmperometricDetectionD7284 Test Method for Total Cyanide in Water by Micro Di
16、stillation followed by Flow Injection Analysis with Gas DiffusionSeparation and Amperometric DetectionD7365 Practice for Sampling, Preservation and Mitigating Interferences in Water Samples for Analysis of CyanideD7511 Test Method for Total Cyanide by Segmented Flow Injection Analysis, In-Line Ultra
17、violet Digestion and AmperometricDetection2.2 U.S. EPA Methods:4EPA OIA-1677 Available Cyanide in WaterEPA Method 335.2 Cyanide, Total (Titrimetric; Spectrophotometric)EPA Method 335.4 Determination of Total Cyanide by Semi-Automated Colorimetry3. Terminology3.1 DefinitionsFor definitions of terms u
18、sed in this guide, refer to Terminology D1129 and Guide D6696.3.2 Definitions of Terms Specific to This Standard:3.2.1 mine rock, nore, waste rock or overburden excavated in order to construct an ore-processing site, or recover metals orminerals during mining operations; or coarse processed ore such
19、 as heap-leach spoils.3.2.2 nominal size, nin sampling, for a screen of the standard series, the opening that would pass 95 % of a representativesample.3.2.3 refrigeration, nstoring the sample between its freezing point and 6C.4. Summary of Guide4.1 Samples are collected in appropriate containers at
20、 the sampling site, optionally field preserved, refrigerated, and transportedto the laboratory where they are weighed, optionally sub-sampled, the moisture is determined or aqueous mass estimated, andcyanides are extracted prior to analysis. Results of the analysis of the extract are applied to the
21、original solid sample to determinethe apparent content of cyanides on the basis of dry weight.5. Significance and Use5.1 This guide is intended as a means for obtaining an extract from mine rock and soil samples to measure cyanide content inthe aqueous portion of the sample on a dry weight basis. Cy
22、anide is analyzed in mine rock and soil extracts for measurement ofcyanide concentration; however, improper sample collection and extraction can result in significant positive or negative bias.5.2 This guide is designed to mobilize aqueous cyanides present in the solids, so that the resulting extrac
23、t can be used to assessleachate that could potentially be produced from mine rock or soil.5.3 This guide is not intended to simulate actual site leaching conditions.5.4 This guide produces extracts that are amenable to the determination of trace cyanides. When trace cyanides are beingdetermined, it
24、is especially important that precautions be taken in sample preservation, storage, and handling to avoid possiblecontamination of the extracts.5.5 This guide uses a comparative test method and is intended for use as a routine method for monitoring mine rock and soils.It is assumed that all who use t
25、his guide will be trained analysts capable of performing it skillfully and safely. It is expected thatwork will be performed in a properly equipped laboratory applying appropriate quality control practices such as those describedin Guide D3856.5.6 This guide identifies proper methods for obtaining m
26、ine rock and soil samples for the specific purpose of measuring cyanideconcentrations.6. Interferences6.1 Many interferences are known for the analysis of cyanide and could effect the results of the analysis of extracts producedusing this guide. Refer to Practice D7365 for proper handling of the ext
27、racts during sampling, mitigation of interferences, andpreservation prior to cyanide analysis.4 Available from United States Environmental Protection Agency (EPA), Ariel Rios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460, http:/www.epa.gov.D7572 1526.2 Unless otherwise specified, samples m
28、ust be extracted as soon as possible after sampling and the extracts must be analyzedwithin 14 days; however, it is recommended to estimate the actual holding time for each new sample matrix as described in PracticeD4841. Certain sample matrices may require immediate analysis to avoid cyanide degrad
29、ation due to interferences.Aholding timestudy is required if there is evidence that cyanide degradation occurs from interferences which would cause the holding time tobe less than specified in this guide or Practice D7365. Potential interferences for cyanide analytical methods are shown in Table1.7.
30、 Apparatus7.1 Agitation Equipment, of any type that rotates the extraction vessel in an end-over-end fashion at a rate of 30 6 2 r/min suchthat the axis of rotation is horizontal and it passes through the center of the bottle (see Fig. 1).7.2 Drying Pans or Dishes, for moisture content determination
31、s, 500 g to 8 kg capacity.7.3 Drying OvenAny thermostatically controlled drying oven capable of maintaining a steady temperature of 62C in a rangeof 100 to 110C.7.4 Extraction Vessels, cylindrical, wide-mouth, of a composition suitable to the nature of the mine rock or soil and cyanideanalyses to be
32、 performed, constructed of materials that will not allow sorption of the constituents of interest, and sturdy enoughto withstand the impact of the falling sample fragments. The size of the container should be selected so that the sample, plusextraction fluid occupy approximately 5095 % of the contai
33、ner in order to provide good mixing without overfilling. Thecontainers must have water-tight closures of sufficient diameter to fill with the samples.7.5 Filtration Device, pressure or vacuum of a composition suitable to the nature of the analyses to be performed and equippedwith a pre-washed glass
34、wool or equivalent filter. An assembly for pre-filtration or a centrifuge may be required if filtration isdifficult. (WarningAvoid passing excessive amounts of air through the sample during filtration to prevent liberation of toxichydrogen cyanide or cyanogen chloride gas.)7.6 Laboratory Balance, ca
35、pable of weighing to 1.0 g.7.7 pH Meter, with a readability of 0.01 units and an accuracy of at least 60.1 units at 25C.7.8 Riffle SplitterA stationary sampler comprising an even number of equally-sized, adjacent chutes discharging in oppositedirections. For use with this practice, there must be a m
36、inimum of twelve contained chutes (not bars) with an opening width ofat least 3 times the nominal size.NOTE 1For riffle splitting finer materials (12.5 mm) it is recommended not to exceed 312 times nominal size as it is required that the full width of the rifflebe used since the accuracy of the spli
37、t increases with the number of chutes. For free-flowing materials, the 3 times top size may be reduced to 112 timesprovided it is ascertained that there is no chute plugging for a particular material.7.9 Rotary Sample DividerA rotating sampler fed from a single point comprising equally-sized or adju
38、stable proportionalcollection pans. For use with this guide, there must be a minimum opening width of at least 3 times the nominal size.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall be used in this guide. Unless otherwise indicated, it is intended that allreagents shall conform to t
39、he specifications of the Committee on Analytical Reagents of the American Chemical Society, wheresuch specifications are available.5 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the deter
40、mination.8.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water that meets thepurity specifications of Type I or Type II water, presented in Specification D1193.8.3 Concentrated Sodium Hydroxide Solution (0.4 M)In a 1-L volumetric flask, dissolve
41、 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 M NaOH inreagent water and dilute to volume.8.5 Sample BottlesSee Section 10.4.1 for further information about sample bottles.9. Hazards9.1 Warni
42、ngBecause of the toxicity of cyanide, great care must be exercised in its handling. Acidification of cyanidesolutions produces toxic hydrocyanic acid (HCN). Adequate ventilation is necessary when handling cyanide solutions and a fumehood should be utilized whenever possible.5 Reagent Chemicals, Amer
43、ican Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormula
44、ry, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD. (http:/)D7572 153TABLE 1 Examples of Potential Interferences if not Mitigated in Standard Cyanide MethodsNOTE 1Alkyl halides were identified as a potential interference for the distillation methods, however they are not normally found in
45、 soil and minerock.Method Description Measurement Interferences NumberTotalCyanideAutomatedUVColorimetric AldehydesColorFatty AcidsKetonesMercuryNitrateNitriteOxidantsSulfidesTurbiditySulfur CompoundsThiocyanateCFR Kelada-01D4374TotalCyanideManualDistillationMgCl2Amperometric AldehydesCarbonatesKeto
46、nesNitriteNitrateOxidantsSulfideSulfur CompoundsThiocyanateD7284D2036, Test Method ATotalCyanideManualDistillationMgCl2Manual orAutomatedColorimetricAldehydesCarbonatesFatty AcidsKetonesNitrateNitriteOxidantsSugarsSulfideSulfur CompoundsThiocyanateColorTurbidityD2036, Test Method AStandard Methods 4
47、500-CN C/EEPA Method 335.2EPA Method 335.4TotalCyanideManualDistillationMgCl2ISE AldehydesCarbonatesFatty AcidsKetonesNitrateNitriteOxidantsSulfideSulfur CompoundsThiocyanateColorTurbidityD2036, Test Method ATotalCyanideManualDistillationMgCl2Titrimetric AldehydesCarbonatesFatty AcidsKetonesNitrateN
48、itriteOxidantsSugarsSulfideSulfur CompoundsThiocyanateTurbidityD2036, Test Method ATotalCyanideMicrodistillationAmperometric CarbonatesOxidantsSulfideD7284TotalCyanideUV/FIA Amperometric CarbonatesOxidantsSulfideD7511D7572 1549.2 WarningMany of the reagents used in these test methods are highly toxi
49、c. These reagents and their solutions andextracted solids must be disposed of properly.TABLE 1 ContinuedMethod Description Measurement Interferences NumberAvailableCyanideFlow InjectionLigand ExchangeAmperometric CarbonatesOxidantsSulfideD6888EPA OIA-1677CyanideAmenable toChlorinationAlkalineChlorination andManualDistillationsManualColorimetricAldehydesCarbonatesFatty AcidsKetonesNitrateNitriteOxidantsSulfideSulfur CompoundsThiocyanateColorTurbidityUnknowns that cause negativeresultsD2036, Test Method BWeak AcidDissociableCyanideBufferedDist
