**SW-846 Update V 9013A - 1 Revision 2 July 2014**  **METHOD 9013A**

**CYANIDE EXTRACTION PROCEDURE FOR SOLIDS AND OILS**

**SW-846 is not intended to be an analytical trainin g manual. Therefore, method**  **procedures are written based on the assumption that they will be followed by analysts who are**  **formally trained in at least the basic principles o f chemical analysis and in the use of the subject**  **technology.**

**In addition, SW-846 methods, with the exception of required method use for the analysis**  **of method defined parameters, are intended to be gu idance methods which contain general**  **information on how to perform an analytical procedu re or technique which a laboratory can use**  **as a basic starting point for generating its own de tailed standard operating procedure (SOP),**  **either for its own general use or for a specific pr oject application. The performance data**  **included in this method are for guidance purposes o nly, and are not intended to be and must not**  **be used as absolute QC acceptance criteria for purp oses of laboratory accreditation.** 

**1.0 SCOPE AND APPLICATION**

**1.1 The extraction procedure described in this met hod is designed for the extraction**  **of soluble and insoluble cyanides from solid, oil, and multi-phase wastes. The resulting**  **extraction solutions may be analyzed for total cyan ide and/or cyanides amenable to chlorination**  **(e.g., Methods 9010, 9012 and 9014) as well as anal yzed for metal cyanide complexes (e.g.,**  **Method 9015).**

**1.2 Prior to employing this method, analysts shoul d consult the disclaimer** 

**statement at the front of the manual and the inform ation in Chapter Two for guidance on the**  **intended flexibility in the choice of methods, appa ratus, materials, reagents, and supplies, and**  **on the responsibilities of the analyst for demonstr ating that the techniques employed are**  **appropriate for the analytes of interest, in the ma trix of interest, and at the levels of concern.** 

**In addition, analysts and data users are advised t hat, except where explicitly required in**  **a regulation, the use of SW-846 methods is** not **mandatory in response to Federal testing requirements. The information contained in this me**  **thod is provided by EPA as guidance to be used by the analyst and the regulated community in**  **making judgments necessary to generate results that meet the data quality objectives for t**  **he intended application.**

**1.3 This method is restricted to use by, or under supervision of, properly**  **experienced and trained personnel. Each analyst mu st demonstrate the ability to generate**  **acceptable results with this method.**

**2.0 SUMMARY OF METHOD**

**The waste sample is extracted with water at pH 10 or greater, and the extract distilled**  **and analyzed (e.g., by Methods 9010, 9012 and 9014) . Samples that contain free water are**  **filtered and separated into an aqueous component an d a combined oil and solid component.**  **The nonaqueous component is then extracted, and an aliquot of the extract combined with an**  **aliquot of the filtrate in proportion to the compos ition of the sample. Alternatively, the**  **components may be analyzed separately, and cyanide levels reported for each component. .** **SW-846 Update V 9013A - 2 Revision 2 July 2014**  **In the presence of free iron and high levels of sus pended solids, some cyanide may combine**  **with iron to form iron cyanide precipitates or poss ibly adsorb to suspended solids under the very**  **low pH conditions encountered during the total cyan ide distillation step (e.g., Methods 9010 and**  **9012) (Refs. 1-6). When this occurs, some cyanide may remain in the distillation flask and not** 
**be distilled over into the absorber solution, resul ting in incomplete recovery of cyanide.**  **Therefore, alkaline extraction followed by distilla tion and analysis of the extract is the preferred**  **method for determining total and amenable cyanide i n solid samples.** 

**NOTE : This method has not been validated for recovery o**  **f free cyanide. Studies indicate that free cyanide may not be fully recovered for certain**  **waste types. If recovery of free cyanide is important to meet project objectives, spiking studi**  **es should be performed for the specific matrices being tested.** 

**3.0 DEFINITIONS**

**Refer to Chapter One, Chapter Three, and the manuf acturer's instructions for definitions**  **that may be relevant to this procedure.**

**4.0 INTERFERENCES**

**4.1 Solvents, reagents, glassware, and other sampl e processing hardware may**  **yield artifacts and/or interferences to sample anal ysis. All of these materials must be** 

**demonstrated to be free from interferences under th e conditions of the analysis by analyzing**  **method blanks. Specific selection of reagents and purification of solvents by distillation in all**  **glass systems may be necessary. Refer to each meth od to be used for specific guidance on**  **quality control procedures and to Chapter Three for general guidance on the cleaning of**  **glassware.**

**4.2 Chlorine and sulfide are potential interferenc es in this method. Interferences**  **are eliminated or reduced by using the distillation procedure. Distillation of samples for cyanide**  **can result in both positive and negative bias depen ding upon the matrix of the sample. All**  **interferences should be evaluated prior to the dist illation of unknown samples. Negative bias is**  **detected by incomplete spike recoveries. Positive bias cannot be detected using matrix spikes.**  **Thiosulfate, sulfite, and other Sulfur (IV) oxides react with cyanide during distillation resulting in**  **a negative bias. Levels of the compounds below 20 mg/L do not generally interfere.** 

**4.3 Oxidizing agents (such as chlorine) decompose most cyanide in solution.**  **Chlorine interferences can be removed by adding an excess of sodium arsenite to the waste**  **prior to preservation and storage of the sample. T his reduces the chlorine to chloride which** 

**does not interfere.**

**4.4 Sulfide interference can be removed by adding an excess of bismuth nitrate to**  **the waste (to precipitate the sulfide) before disti llation. Samples that contain hydrogen sulfide,**  **metal sulfides, or other compounds that may produce hydrogen sulfide during the distillation**  **should be treated by the addition of bismuth nitrat e.** 

**NOTE : ASTM studies have indicated that [Fe(CN)**  **6 ]**  **-3 recoveries may be low when distilling**  **samples containing bismuth nitrate. SW-846 Update V 9013A - 3 Revision 2**  **July 2014 4.5 High results may be obtained for samples that**  **contain nitrate and/or nitrite. During the distillation, nitrate and nitrite will f**  **orm nitrous acid, which will react with some organi c**  **compounds to form oximes. These compounds, once fo rmed, will decompose under test**  **conditions to generate HCN. The possibility of int erference of nitrate and nitrite is minimized by**  **pretreatment with sulfamic acid just before distill ation. Nitrate and nitrite are interferences when**  **present at levels higher than 10 mg/L and in conjun ction with certain organic compounds and**  **thiocyanate.**

**4.6 Thiocyanate is reported to be an interferent w hen present at very high levels.**  **Levels greater than 10 mg/L can interfere by decrea sing the cyanide concentration. Nitrate and**  **thiocyanate combined is a positive interference.**

**4.7 Fatty acids, detergents, surfactants, and oth er compounds may cause foaming**  **during the distillation when they are present in hi gh concentrations and may make the endpoint** 

**for the titrimetric determination difficult to dete ct. They may be extracted at pH 6-7 to eliminate** 

**this interference.**

**5.0 SAFETY**

**5.1 This method does not address all safety issues associated with its use. The**  **laboratory is responsible for maintaining a safe wo rk environment and a current awareness file**  **of OSHA regulations regarding the safe handling of the chemicals specified in this method. A**  **reference file of material safety data sheets (MSDS s) should be available to all personnel**  **involved in these analyses.**

**WARNING : KCN and NaCN are highly toxic. Avoid skin and e**  **ye contact and inhalation.**

**5.2 Because of the toxicity of cyanide, exercise g reat care in its handling.**  **Acidification of cyanide solutions produces toxic, gaseous hydrogen cyanide (HCN). Perform all**  **manipulations in the hood so that any HCN gas that is formed is safely vented. Wear hand and**  **eye protection at all times when working with cyani de.** 

**6.0 EQUIPMENT AND SUPPLIES**

**The mention of trade names or commercial products in this manual is for illustrative**  **purposes only, and does not constitute an EPA endor sement or exclusive recommendation for**  **use. The products and instrument settings cited in SW-846 methods represent those products**  **and settings used during method development or subs equently evaluated by the Agency.**  **Glassware, reagents, supplies, equipment, and setti ngs other than those listed in this manual**  **may be employed provided that method performance ap propriate for the intended application** 

**has been demonstrated and documented.**

**This section does not list all common laboratory g lassware (e.g., beakers and flasks)**  **that might be used.**

**6.1 Extractor - Any suitable device that sufficien tly agitates a sealed container of**  **one liter volume or greater. For the purpose of th is analysis, agitation is sufficient when (1) all**  **sample surfaces are continuously brought into conta ct with extraction fluid, and (2) the agitation**  **prevents stratification of the sample and fluid. SW-846 Update V 9013A - 4 Revision 2**  **July 2014 6.2 Buchner funnel apparatus** 

**6.2.1 Buchner funnel - 500-mL capacity, with 1-L v acuum filtration flask** 

**6.2.2 Glass wool - Suitable for filtering, 0.8-μm diameter such as Corning**  **Pyrex 3950**

**6.2.3 Millipore 0.45-μm membrane filters - Suitabl e for filtering into a** 

**vacuum filtration flask**

**6.2.4 Vacuum source - Vacuum pump or a water drive n aspirator. A**  **valve or stopcock to release vacuum is required.**

**6.3 Top-loading balance - Capable of weighing 0.1 g** 

**6.4 Separatory funnels - 500-mL**

**6.5 pH papers or test strips**

**7.0 REAGENTS AND STANDARDS**

**7.1 Reagent grade chemicals must be used in all te sts. Unless otherwise**  **indicated, it is intended that all reagents conform to the specifications of the Committee on**  **Analytical Reagents of the American Chemical Societ y, where such specifications are available.**  **Other grades may be used, provided it is first asce rtained that the reagent is of sufficiently high**  **purity to permit its use without lessening the accu racy of the determination. Reagents should be**  **stored in glass to prevent the leaching of contamin ants from plastic containers. Note, however,**  **that sodium hydroxide solutions of relatively moder ate strength (i.e., 4.1 g/L and greater), should**  **be stored in HDPE plastic containers whenever possi ble.** 

**7.2 Reagent water - Reagent water must be interfer ence free. All references to**  **water in this method refer to reagent water, as def ined in Chapter One, unless otherwise**  **specified.**

**7.3 Sodium hydroxide (50% w/v), NaOH - Commerciall y available** 

**7.4 Sulfuric acid (50%v/v), H 2**  **SO 4**  **- Commercially available**

**7.5 n-Hexane, C 6**  **H 14** 

**8.0 SAMPLE COLLECTION, PRESERVATION, AND STORAGE**

**Sample collection, preservation and storage requir ements may vary by EPA program**  **and may be specified in a regulation or project pla nning document that requires compliance**  **monitoring for a given contaminant. Where such req uirements are specified in the regulation,**  **follow those requirements. In the absence of speci fic regulatory requirements, use the following**  **information as guidance in determining the sample c ollection, preservation and storage**  **requirements.**

**8.1 See the introductory material to Chapter Three , “Inorganic Analytes.”** **SW-846 Update V 9013A - 5 Revision 2 July 2014**  **8.2 Samples should be collected in plastic or glas s (preferably plastic) containers** 

**that are either amber or covered with aluminum foil so as to filter light at 400 nm and below and**  **prevent photodecomposition of metal cyanide complex es. All containers must be thoroughly**  **cleaned and rinsed prior to use. All sample contai ners must be prewashed with acids, water,**  **and metal-free detergents, if necessary, depending on the use history of the container. For**  **further information, see Chapter Three.**

**8.3 Store solid samples at ≤6 oC after collection and prior to extraction. Bring**  **samples to room temperature just prior to extractio n.** 

**8.4 Store solid samples at ≤6 oC for no longer tha n 14 days. Solid phase samples**  **must be extracted within 14 days of sample collecti on.** 

**8.5 After generation, store solid phase extract so lutions at ≤6 oC prior to analysis by**  **the determinative method. Bring the extract soluti ons to room temperature just prior to analysis.** 

**8.6 Store solid phase extract solutions at ≤6 oC f or no longer than 14 days.**  **Analysis of solid phase extracts must be performed within 14 days of extract generation.** 

**8.7 If fatty acids, detergents, and surfactants ar e a problem, they may be extracted**  **using the following procedure. Acidify the sample with acetic acid (1.6 M) to pH 6.0 to 7.0.** 

**CAUTION : This procedure can produce lethal HCN gas.** 

**Extract with isooctane, hexane, or chloroform (pref erence in order named) with solvent volume**  **equal to 20% of the sample volume. One extraction is usually adequate to reduce the**  **compounds below the interference level. Avoid mult iple extractions or a long contact time at low**  **pH in order to keep the loss of HCN at a minimum. When the extraction is completed,**  **immediately raise the pH of the sample to 12 with a 50% NaOH solution.** 

**8.7 Also see the applicable distillation and deter minative method for additional**  **guidance.**

**9.0 QUALITY CONTROL**

**9.1 Refer to Chapter One for guidance on quality a ssurance (QA) and quality**  **control (QC) protocols. When inconsistencies exist between QC guidelines, method-specific**  **QC criteria take precedence over both technique-spe cific criteria and those criteria given in**  **Chapter One, and technique specific QC criteria tak e precedence over the criteria in Chapter**  **One. Any effort involving the collection of analyt ical data should include development of a**  **structured and systematic planning document, such a s a Quality Assurance Project Plan**  **(QAPP) or a Sampling and Analysis Plan (SAP), which translates project objectives and**  **specifications into directions for those that will implement the project and assess the results.**  **Each laboratory should maintain a formal quality as surance program. The laboratory should**  **also maintain records to document the quality of th e data generated. All data sheets and quality** 

**control data should be maintained for reference or inspection.** 

**9.2 Initial demonstration of proficiency**

**Each laboratory must demonstrate initial proficien cy with each sample preparation and**  **determinative method combination it utilizes by gen erating data of acceptable accuracy and**  **precision for target analytes in a clean matrix. T he laboratory must also repeat the** **SW-846 Update V 9013A - 6 Revision 2 July 2014**  **demonstration of proficiency whenever new staff mem bers are trained or significant changes in** 

**instrumentation are made.**

**9.3 Initially, before processing any samples, the analyst should demonstrate that all**  **parts of the equipment in contact with the sample a nd reagents are interference free. This is**  **accomplished through the analysis of a method blank . As a continuing check, each time**  **samples are extracted and analyzed, and when there is a change in reagents, a method blank**  **should be prepared and analyzed for the compounds o f interest as a safeguard against chronic**  **laboratory contamination. If a measurable absorban ce is observed at or in close proximity to**  **the measurement wavelength of the target analyte th at would prevent the accurate**  **determination of that analyte, determine the source and eliminate it, if possible, before**  **processing the samples. The blanks should be carri ed through all stages of sample preparation**  **and analysis. When new reagents or chemicals are r eceived, the laboratory should monitor the**  **preparation and/or analysis blanks associated with samples for any signs of contamination. It is**  **not necessary to test every new batch of reagents o r chemicals prior to sample preparation if**  **the source shows no prior problems. However, if re agents are changed during a preparation**  **batch, separate blanks need to be prepared for each set of reagents.** 

**The laboratory should not subtract the results of the method blank from those of any**  **associated samples. Such "blank subtraction" may l ead to negative sample results. If the**  **method blank results do not meet the project specif ic acceptance criteria and reanalysis is not**  **practical, then the data user should be provided wi th the sample results, the method blank**  **results, and a discussion of the corrective actions undertaken by the laboratory.** 

**9.4 Sample quality control for preparation and ana lysis** 

**The laboratory must also have procedures for docum enting the effect of the matrix on**  **method performance (precision, accuracy, method sen sitivity). At a minimum, this should**  **include the analysis of QC samples including a meth od blank, a matrix spike, a duplicate, and a**  **laboratory control sample in each analytical batch. Any method blanks, matrix spike samples,**  **and replicate samples must be subjected to the same analytical procedures (Sec. 11.0) as**  **those used on actual samples.**

**9.4.1 Method blank - For each batch of solid phase samples extracted using**  **this method, at least one method blank should also be carried through the entire sample**  **extraction, preparation and analytical process. A method blank is prepared by using a**  **specified volume or weight of the extraction soluti on and then carrying it through the**  **appropriate steps of the extraction and analytical process. These steps may include, but**  **are not limited to, prefiltering, extraction, dilut ion, filtering, and analysis. If the method**  **blank does not contain target analytes at a level t hat exceeds the project specific criteria**  **requirements, then the method blank would be consid ered acceptable. In the absence**  **of project specific criteria, if the blank is less than the lower limit of detection, less than**  **10% of the regulatory limit, or less than 10% of th e lowest sample concentration,**  **whichever is greater, then the method blank is cons idered acceptable. If the method**  **blank cannot be considered acceptable, the method b lank should be re-run once, and if**  **still unacceptable, then all samples after the last acceptable method blank must be**  **prepared again and reanalyzed along with the other appropriate batch QC samples.**  **These blanks will be useful in determining if sampl es are being contaminated. If the**  **method blank exceeds the criteria, but the samples are all either below the reporting**  **level or below the applicable action level or other criteria, then the data should not be**  **rejected based on this analysis.**

**9.4.2 Matrix spike (MS)/ Duplicate - For each batc h of solid phase samples**  **extracted using this method, at least one matrix sp ike (MS) and one duplicate unspiked** **SW-846 Update V 9013A - 7 Revision 2 July 2014**  **sample or one matrix spike/matrix spike duplicate ( MS/MSD) pair should be carried**  **through the entire sample extraction, preparation a nd analytical process. Spiking is**  **performed directly on the solid sample matrix prior to extraction in order to assess the**  **efficiency of the extraction procedure. The decisi on on whether to prepare and analyze**  **duplicate samples or a MS/MSD must be based on a kn owledge of the samples in the**  **sample batch. If samples are expected to contain t he target analyte, laboratories may**  **use a matrix spike (MS) and a duplicate analysis of an unspiked field sample. If samples**  **are not expected to contain the target analyte, the laboratories should use a MS/MSD**  **pair. A separate spiked sample and a separate dupl icate unspiked sample may be**  **analyzed in lieu of MS/MSD analyses.**

**9.4.3 LCS - For each batch of samples processed, a t least one LCS must**  **be carried through the entire sample preparation an d analytical process, as described in**  **Chapter One. The LCS is a reagent water solution f ortified with method analytes at**  **known concentrations, prepared from a different sou rce than that used to prepare the**  **calibration standards. The LCS should be spiked wi th each analyte of interest at the**  **project-specific action level or when lacking proje ct specific action levels, between the**  **low- and mid-level standards. Concurrent analyses of standard reference materials**  **(SRMs) containing known values of analytes in the m edia of interest are recommended**  **and may be used as an LCS.**

**NOTE : If insoluble or complexed cyanides (such as Pruss**  **ian blue) are of interest, the recovery of cyanide should be evaluated from a simi**  **lar species as that which is expected to be present in the samples.** 

**9.4.4 In order to verify the extraction process at the Lower Level of**  **Quantitation (LLOQ), a matrix-free LLOQ check stand ard is prepared by spiking a clean**  **control material with the analyte(s) of interest at the predicted LLOQ concentration**  **level(s). This LLOQ check is carried through the sa me preparation procedures as the**  **environmental samples and other QC. Recovery should be within established limits, or**  **other such project required acceptance limits, for precision and bias to verify the data**  **reporting limits. Until the laboratory has sufficie nt data to determine acceptance limits**  **statistically, a limit of 20% +/- the LCS Criteria may be used for the LLOQ acceptance**  **criteria. The frequency of this LLOQ verification i s not mandated, but should be**  **determined by the laboratory’s quality plan. Addit ional information on LLOQ can be**  **found in 8000D, Section 9.7.**

**9.5 Standard quality assurance practices should be used with this method as**  **included in appropriate systematic planning documen ts and laboratory SOPs.** 

**9.6 Also refer to the applicable distillation and determinative method for appropriate**  **quality control guidelines.**

**10.0 CALIBRATION AND STANDARDIZATION**

**There are no calibration or standardization steps directly associated with this procedure.** **SW-846 Update V 9013A - 8 Revision 2 July 2014**  **11.0 PROCEDURE**

**11.1 If the waste does not contain any free aqueou s phase, go to Sec. 11.6. If the**  **sample is a homogeneous fluid or slurry that does n ot separate or settle in the distillation flask**  **when using a polytetrafluorethylene (PTFE) coated m agnetic stirring bar (but mixes so that the**  **solids are entirely suspended); the sample may be a nalyzed by Method 9010 without an**  **extraction step.**

**11.2 Assemble Buchner funnel apparatus. Unroll gl ass filtering fiber and fold the**  **fiber over itself several times to make a pad about 1 cm thick when lightly compressed. Cut the**  **pad to fit the Buchner funnel. Weigh the pad, and then place it in the funnel. Turn the aspirator**  **on and wet the pad with a known amount of water.**

**11.3 Transfer the sample to the Buchner funnel in small aliquots, first decanting the**  **fluid. Rinse the sample container with known amoun ts of water and add the rinses to the** 

**Buchner funnel. Record the total volume of rinses used. When no free water remains in the**  **funnel, slowly open the stopcock to allow air to en ter the vacuum flask. A small amount of**  **sediment may have passed through the glass fiber pa d. This will not interfere with the analysis.** 

**11.4 Transfer the solid and the glass fiber pad to a tared weighing dish. Since most**  **greases and oils will not pass through the fiber pa d, solids, oils, and greases will be extracted**  **together. If the filtrate includes an oil phase, t ransfer the filtrate to a separatory funnel. Colle**  **ct and measure the volume of the aqueous phase. Trans**  **fer the oil phase to the weighing dish**

**with the solid.**

**11.5 Weigh the dish containing solid, oil (if any) , and filter pad. Subtract the weight**  **of the dry filter pad. Calculate the net volume of water present in the original sample by**  **subtracting the total volume of rinses used from th e measured volume of the filtrate.** 

**11.6 Place the following in a 1-L, wide-mouthed bo ttle:** 

**500 mL water, 5 mL 50% w/v NaOH, and**  **50 mL n-hexane (if a heavy grease is present).**

**If the weight of the solids (Sec. 11.5) is greater than 25 g, weigh out a representative aliquot of**  **25 g and add it to the bottle; otherwise add all of the solids. Cap the bottle.** 

**11.7 The extract must be maintained above pH 10 th roughout the extraction step**  **and subsequent filtration. Since some samples may release acid, the pH must be monitored as** 

**follows. Shake the extraction bottle and after one minute, check the pH. If the pH is below 12,** 

**add 50% NaOH in 5 mL increments until it is at leas t 12. Recap the bottle, and repeat the**  **procedure until the pH does not drop.**

**11.8 Place the bottle or bottles in the tumbler, m aking sure there is enough foam** 

**insulation to cushion the bottle. Turn the tumbler on and allow the extraction to run for about 16** 

**hours.**

**11.9 For extract solutions to be subsequently dist illed for total cyanide or cyanides**  **amenable to chlorination (e.g., Method 9010 or 9012 ):** **SW-846 Update V 9013A - 9 Revision 2 July 2014**  **11.9.1 Prepare a Buchner funnel apparatus as in Se c. 11.2 with a glass**  **fiber pad filter.**

**11.9.2 Decant the extract to the Buchner funnel. Full recovery of the**  **extract is not necessary.**

**11.10 For extract solutions to be subsequently ana lyzed for metal cyanide complexes**  **(Method 9015):**

**11.10.1 Check the pH of the extraction solution. Adjust the pH to between**  **11 and 12, using 50% H 2**  **SO 4**  **. Recap the bottle and mix the solution. Repeat t he**  **procedure until the pH is in the proper range.**

**11.10.2 Prepare a Buchner funnel apparatus with a 0.45-μm membrane** 

**filter.**

**11.10.3 Decant the extract to the Buchner funnel. Full recovery of the**  **extract is not necessary.**

**11.11 If the extract contains an oil phase, separa te the aqueous phase using a**  **separatory funnel. Neither the separation nor the filtration are critical, but are necessary to be**  **able to measure the volume of the aliquot of the aq ueous extract analyzed. Small amounts of**  **suspended solids and oil emulsions will not interfe re.** 

**11.12 At this point, an aliquot of the filtrate of the original sample may be combined**  **with an aliquot of the extract in a proportion repr esentative of the sample. Alternatively, they**  **may be distilled and analyzed separately and concen trations given for each phase. This is**  **described by the following equation:**



## ( ) ( ) ( )

( ) ( )

( ) **d c** 

**b a** 



### mL

**Fluid Extraction**  **Total mL** 

**Filtrate Sample**  **Total**

**g d**  **Soli Total**  **g Extracted**  **Solid**

**mL Aliquot**  **Extract mL** 

**Aliquot Sample**  **Liquid**

× =

**a From Sec. 11.6. Weight of solid sample used for ex**  **traction.**

**b From Sec. 11.5. Weight of solids and oil phase wit**  **h the dry weight of filter and tared dish**

**subtracted.**

**c Includes volume of all rinses added to the filtrate**  **(Secs. 11.2 and 11.3).**

**d 500 mL of water plus total volume of NaOH solution.**  **Does not include hexane, which is subsequently removed (Sec. 11.11).** 

**Alternatively, the aliquots may be distilled and an alyzed separately, concentrations for each**  **phase reported separately, and the amounts of each phase present in the sample reported**  **separately.**

**11.13 Determination of percent dry weight**

**In certain cases, the reporting of sample results is desired based on a dry weight basis.**  **When such data are desired, a separate portion of s ample for this determination should be**  **weighed out at the same time as the portion used fo r analytical determination.** **SW-846 Update V 9013A - 10 Revision 2 July 2014**  **CAUTION : The drying oven should be contained in a hood or**  **vented. Significant laboratory contamination may result from a heavily contaminate**  **d waste material.**

**11.13.1 Immediately after weighing the sample aliq uot to be extracted,**  **weigh an additional 5-10 g aliquot of the sample in to a tared crucible. Dry this aliquot**  **overnight at 105 °C. Allow to cool in a desiccator before weighing.** 

**11.13.2. Calculate the % dry weight as follows:**



### 100 **sample of**  **g sample**  **dry of**  **g Weight**  **Dry %**  ×

=

**NOTE : This oven-dried aliquot is not used for the extra**  **ction and should be appropriately disposed of once the dry weight is determined.** 

**12.0 DATA ANALYSIS AND CALCULATIONS**

**12.1 There are no determinative data analysis and calculation steps directly**  **associated with this procedure. Follow the directi ons given in the determinative method.** 

**12.2 Results must be reported in units commensurat e with their intended use and all**  **dilutions must be taken into account when computing final results.** 

**13.0 METHOD PERFORMANCE**

**13.1 Performance data and related information are provided in SW-846 methods**  **only as examples and guidance. The data do not rep resent required performance goals for**  **users of the methods. Instead, performance goals s hould be developed on a project-specific**  **basis, and the laboratory should establish in-house QC performance criteria for the application**  **of this method. These performance data are not int ended to be and must not be used as**  **absolute QC acceptance criteria for purposes of lab oratory accreditation.** 

**13.2 In a single laboratory study, recoveries of 7 8-95% were reported for soils spiked** 

**with Fe 4**  **[Fe(CN) 6**  **] 3**  **, an insoluble iron cyanide compound (see Table 1.) . These data are**  **provided for guidance purposes only.**

**14.0 POLLUTION PREVENTION**

**14.1 Pollution prevention encompasses any techniqu e that reduces or eliminates the**  **quantity and/or toxicity of waste at the point of g eneration. Numerous opportunities for pollution**  **prevention exist in laboratory operation. The EPA has established a preferred hierarchy of**  **environmental management techniques that places pol lution prevention as the management**  **option of first choice. Whenever feasible, laborat ory personnel should use pollution prevention**  **techniques to address their waste generation. When wastes cannot be feasibly reduced at the**  **source, the Agency recommends recycling as the next best option.** 

**14.2 For information about pollution prevention th at may be applicable to** 

**laboratories and research institutions consult** Less is Better: Laboratory Chemical Management for Waste Reduction, **a free publication available from the American Che mical Society (ACS),**  **Committee on Chemical Safety, http://portal.acs.org/portal/fileFetch/C/WPCP_01229**  **0/pdf/WPCP_012290.pdf. SW-846 Update V 9013A - 11 Revision 2**  **July 2014 15.0 WASTE MANAGEMENT** 

**The Environmental Protection Agency requires that laboratory waste management**  **practices be conducted consistent with all applicab le rules and regulations. The Agency urges**  **laboratories to protect the air, water, and land by minimizing and controlling all releases from**  **hoods and bench operations, complying with the lett er and spirit of any sewer discharge permits**  **and regulations, and by complying with all solid an d hazardous waste regulations, particularly** 

**the hazardous waste identification rules and land d isposal restrictions. For further information**  **on waste management, consult the ACS publication li sted in Sec. 14.2.** 

**16.0 REFERENCES**

**1. American Society for Testing and Materials, "Und erstanding Cyanide Species," D 6696,**  **ASTM International, 2004. This reference can be pu rchased on line at ASTM’s web site:**  **www.astm.org.**

**2. R. S. Ghosh, D. A. Dzombak, R. G. Luthy, "Equili brium Precipitation and Dissolution of**  **Iron Cyanide Solids in Water,"** Environ. Eng. Sci. **, Vol. 16, 293-313, 1999.**

**3. J. C. L. Meeussen, M. G. Keizer, W. H. van Riems dijk, F. A. M. de Haan, "Dissolution**  **Behavior of Iron Cyanide (Prussian Blue) in Contami nated Soils,"**  Environ. Sci. Technol.

**, Vol. 26, 1832-1838, 1992.** 

**4. J. C. L Meeussen, W. H. Keizer, F. A. M. de Haan , "Chemical Stability and**  **Decomposition Rate of Iron Cyanide Complexes in Soi l Solutions,"**  Environ. Sci.

Technol. **, Vol. 26, 511-516, 1992.**

**5. J. T. Bushey, D. A. Dzombak, "Ferrocyanide Adsor ption on Aluminum Oxides,"**  J. Coll.

Int. Sci. **, Vol. 272, 46-51, 2004.**

**6. T. L. Theis, M. L West, "Effects of Cyanide Comp lexation on the Adsorption of Trace**  **Metals at the Surface of Goethite,"** Environ. Technol. Letters **, Vol. 7, 309-318, 1986.**

**7. The RETEC Group, Inc., "Metal Cyanide Complexes by Anion Exchange**  **Chromatography and UV Detection Method Validation S ummary Report," March, 2004.** 

**17.0 TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION D ATA** 

**The following page contains the table referenced b y this method.** **SW-846 Update V 9013A - 12 Revision 2 July 2014**  **TABLE 1**

**EXAMPLE TOTAL CYANIDE RECOVERIES IN SPIKED SOILS PR EPARED** 

**USING METHOD 9013 EXTRACTION**

**Sample Background Total** 

**Cyanide**

**Concentration a** 
**(μg/g Cyanide) Spiking** 

**Concentration b** 

**(μg/g Cyanide) Average Total**  **Cyanide Recovery**  **b Standard** 

**Deviation c** 

**Soil 1 0.44 500 95% 1.8% (n = 2)**

**Soil 2 0.17 500 78% 0.1% (n = 2)**

**Soil 3 ND 500 86% 6.4% (n = 4)**

a **Total cyanide was determined in the soil extraction solutions using Methods 9010 and 9012.** 

b **Soils were spiked using solid Fe 4**  **[Fe(CN) 6**  **] 3**  **prior to extraction.**

c **n = Number of replicate analyses**

**These data are provided for guidance purposes only.**

**Data taken from Reference 7. SW-846 Update V 9013A - 13 Revision 2**  **July 2014 Appendix A**  **Summary of Revisions to Method 9013 (From Revision 1, November 2004)** 

**1. Improved overall method formatting for consisten cy with new SW-846 methods style**  **guidance. The version number was changed to two an d the date published was updated to**  **July 2014. 2. Significantly updated and expanded “QUALITY CONT**  **ROL” section (Sec. 9.0) for better adherence to current SW-846 method guidelines and f**  **or improved alignment with current universal practices for published analytical method**  **s. 3. Updated “INTERFERENCES” in section 4 to add addi**  **tional information on the effects of**

**certain interferences and deleted reference to meth od 9010.**  **4. The method performance information was updated i n Section 13.2 and Table 1.** 

**5. Minor editorial and technical revisions were mad e throughout to improve method clarity.**  **6. Inserted new section (Sec. 9.4.4) describing the preparation and use of an LLOQ standard.**