1、Designation:D138507D138507 (Reapproved 2013) 1 AnAmerican National Standard Standard Test Method for Hydrazine in Water 1 This standard is issued under the xed designation D1385; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the
2、 year of last revision.Anumber in parentheses indicates the year of last reapproval.A superscript 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. e 1 NOTEThis standard was reapproved wit
3、h editorial changes in January, 2013. 1. Scope 1.1 This test method covers 2 the colorimetric determination of hydrazine in boiler feed waters, condensates, natural, and well watersthathavebeentreatedwithhydrazine(N 2 H 4 ).Thistestmethodisusableintherangefrom5.0to200g/L(ppb)hydrazine. The range is
4、for photometric measurements made at 458 nm in 50 mm cell. Higher concentrations of hydrazine can also be determined by taking a more diluted sample. 1.2 It is the users responsibility to ensure the validity of this test method for untested types of waters. 1.3 The values stated in SI units are to b
5、e regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices a
6、nd determine the applicability of regulatory limitations prior to use. For specic precautionary statements, see 5.3, Note 1, and Footnote 8. 2. Referenced Documents 2.1 ASTM Standards: 3 D1066Practice for Sampling Steam D1129Terminology Relating to Water D1193Specication for Reagent Water D3370Pract
7、ices for Sampling Water from Closed Conduits D5810Guide for Spiking into Aqueous Samples D5847Practice for Writing Quality Control Specications for Standard Test Methods for Water Analysis E60Practice for Analysis of Metals, Ores, and Related Materials by Spectrophotometry E275Practice for Describin
8、g and Measuring Performance of Ultraviolet and Visible Spectrophotometers 3. Terminology 3.1 DenitionsFor denitions of terms used in this test method, refer to Terminology D1129. 4. Summary of Test Method 4.1 When a solution of p-dimethylaminobenzaldehyde in methyl alcohol and hydrochloric acid is a
9、dded to hydrazine in diluted hydrochloric acid solution, a characteristic yellow color of p-dimethylaminobenzalazine is formed. The yellow color formed is proportionaltothehydrazinepresentandisingoodagreementwithBeerslawintherangefrom5.0to200g/L(ppb)hydrazine. 5. Signicance and Use 5.1 Hydrazine is
10、a man-made chemical and is not found in natural waters. The determination of hydrazine is usually made on boiler feedwaters, process waters, and other waters that have been treated with hydrazine (N 2 H 4 ) for the purpose of maintaining 1 This test method is under the jurisdiction ofASTM Committee
11、D19 on Water and is the responsibility of Subcommittee D19.03 on Sampling Water and Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water Current edition approved June 15, 2007Jan. 1, 2013. Published July 2007February 2012. O
12、riginally approved in 1967. Last previous edition approved in 20012007 as D138501.D138507. DOI: 10.1520/D1385-07.10.1520/D1385-07R13E01. 2 Forfurtherinformationonthistestmethod,thefollowingreferencesmaybeofinterest:Watt,G.W.,andChrisp,J.D.,SpectrophotometricMethodfortheDetermination of Hydrazine, An
13、alytical Chemistry, Vol 24, No. 12, 1952, pp. 20062008, and Wood, P. R., Determination of Maleic Hydrazide Residues in Plant and Animal Tissue, Analytical Chemistry, Vol 25, No. 12, 1953, pp. 18791883. 3 ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,orcontactASTMCustomerServiceatservic
14、eastm.org.ForAnnualBookofASTMStandards volume information, refer to the standards Document Summary page on the ASTM website. This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
15、it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version of the standard as published by ASTM is to be considered the official document. Copyright ASTM International, 100 Ba
16、rr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States 1residuals to prevent corrosion by dissolved oxygen. This reducing chemical reacts with dissolved oxygen to form nitrogen and water. However, under certain conditions it can also decompose to form ammonia and nitrogen. Hydr
17、azine is used extensively as a preboiler treatment chemical for high-pressure boilers to scavenge small amounts of dissolved oxygen that are not removed by mechanical aeration. It has the advantage over sulte treatment in that it does not produce any dissolved solids in the boiler water. Hydrazine i
18、s often determined in concentrations below 0.1 mg/L. However, in layup solutions for the protection of idle boilers, hydrazine may be present in concentrations as high as 200 mg/L. 5.2 Additionally, hydrazine provides protection where reducing conditions are required, particularly in mixed metallurg
19、y systems for the protection of the copper alloys. 5.3 Hydrazineisasuspectedcarcinogenandathresholdlimitvalueintheatmosphereof1.0mg/LhasbeensetbyOSHA.When in an aqueous solution, hydrazine will oxidize to nitrogen and water in the presence of air over a relatively short period of time. 6. Interferen
20、ces 6.1 The substances normally present in industrial water do not interfere with the test; however, the hydrazine content may be diminishedbyoxidizingagents,suchaschlorine,bromine,andiodine,collectedwiththesampleorabsorbedbyitpriortotesting. 6.2 Colors in the prescribed wavelengths also interfere,
21、as do other dark colors or turbidities that cannot be overcome. 6.3 Aromatic amines, such as aniline, will also interfere. 7. Apparatus 7.1 PhotometerA spectrophotometer suitable for measurements at 458 nm and capable of holding cells with a light path of 50 mm should be used. Filter photometers and
22、 photometric practices prescribed in this test method shall conform to Practice E60, and spectrophotometers to Practice E275. 7.2 Certain photoelectric lter photometers are capable of measurement at 425 nm, but not at 458 nm. Measurements may be made at 425 nm with a reduction in sensitivity of appr
23、oximately 50% of that possible at 458 nm. 7.3 Instruments that read out in direct concentration can also be used. Manufacturers instructions should be followed. 8. Reagents 8.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all r
24、eagents shall conform to the specications of the Committee on Analytical Reagents of the American Chemical Society, where such specications are available. 4 Other grades may be used, provided it is rst ascertained that the reagent is sufficiently high in purity to permit its use without lessening th
25、e accuracy of the determinations. 8.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water conforming to the requirements quantitative requirements of Type III reagent water in Specication D1193, Type III 8.3 Hydrazine Solution, Stock (1.0 mL = 100
26、 g N 2 H 4 ) Dissolve 0.328 g of hydrazine dihydrochloride (HClNH 2 NH 2 HCl) in 100 mLof water and 10 mLof HCl (sp gr 1.19). Dilute with water to 1 Lin a volumetric ask and mix (Warning, see Note 1). 8.4 Hydrazine Solution, Standard(1.0mL=0.500gN 2 H 4 ) Dilute5.0mLofhydrazinestocksolutionto1Lwithw
27、aterand mix. Prepare as needed. NOTE 1Warning: Hydrazine is a suspected carcinogen and should be handled with care. 5 8.5 Hydrochloric Acid (sp gr 1.19)Concentrated hydrochloric acid (HCl). 8.6 p-DimethylaminobenzaldehydeSolutionDissolve4.0gofp-dimethylaminobenzaldehyde(CH 3 ) 2 NC 6 H 4 CHOin200mL
28、of methyl alcohol (CH 3 OH) and 20 mL of HCl (sp gr 1.19). Store in a dark bottle out of direct sunlight. 9. Sampling 9.1 Collect the sample in accordance with Practices D3370 or Practice D1066, whichever is applicable (Warning, see Note 1). 9.2 Acidify and dilute the sample as soon as taken by addi
29、ng 1 mL of concentrated HCl (sp gr 1.19) to a 100-mL volumetric ask and then pipetting 50 mL of the sample into the ask and diluting to 100 mL. Prepare a blank with water at the same time. 9.3 A smaller sample aliquot should be taken if the hydrazine concentration is greater than 200 g/L. 4 Reagent
30、Chemicals, American Chemical Society Specications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed by the American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and N
31、ational Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD. 5 MacEwen, J. D., Vernot, E. H., Haun, C. C., and Kinkead, E. B., Chronic Inhalation Toxicity of Hydrazine: Onconogenic Effects, in cooperation with the University of California (Irvine) and the Airforce Aero Medical Resea
32、rch Laboratory. D138507 (2013) 1 210. Calibration 10.1 Prepare a series of standard hydrazine solutions by pipetting 0.0, 5.0, 10.0, 25.0, 50.0, 100.0, and 200.0 mLof hydrazine standard solution (1.0 mL= 0.500 g N 2 H 4 ) into 500-mLvolumetric asks.Add 5 mLof HCl (sp gr 1.19) to each ask and dilute
33、with water to 500 mLand mix well.This will give standard solutions containing 0, 5.0, 10.0, 25.0, 50.0, 100, and 200 g/L(ppb) of hydrazine. 10.2 Pipet50.0-mLportionsofthehydrazinestandardsolutionsintoclean,dry100-mLbeakersorasksandproceedasdirected in 11.2. Plot absorbance on the ordinate and microg
34、rams per litre of hydrazine on the abscissa of linear graph paper.Alternately, graph the data in an electronic spreadsheet or use an instrument that reads out in direct concentrations. 10.3 Aseparatecalibrationcurvemustbemadeforeachphotometerandarecalibrationmustbemadeifitisnecessarytochange the cel
35、l, lamp, or lter, or if any other alterations of instrument or reagents are made. Check the curve for each series of tests by running two or more solutions of known hydrazine concentrations. 11. Procedure 11.1 Pipet 50.0 mL of the blank, standard solutions, and acidied diluted sample solutions into
36、clean, dry 100-mL beakers or asks. 11.2 Add 10.0 mL of p-dimethylaminobenzaldehyde solution with a pipet to each beaker or ask and mix well. 11.3 After a minimum of 10 min, but no longer than 100 min, measure the color absorbance of each solution at 458 nm in a 50 mm cell with a spectrophotometer, u
37、sing the blank as reference solution for the initial instrument setting at zero absorbance. The instrument may be calibrated with the standard solutions to read directly in concentration if such capabilities are available. 11.4 Determine the micrograms per litre of hydrazine by referring the absorba
38、nce obtained for the sample to the calibration curve or reading hydrazine concentration directly. 12. Calculation 12.1 Calculatetheconcentrationofhydrazineinmicrogramsperlitre(partsperbillion)inthesamplebyapplyingthefollowing equation for the hydrazine determined in 11.4: hydrazineN 2 H 4 !,g/Lppb!5
39、AB/C where: A = hydrazine indicated by the calibration curve or read directly from the instrument, g/L, B = volume of the ask, g/L, in which the sample was diluted in Section 9.2, mL, and C = volume of the sample in Section 9.2, mL. 13. Precision and Bias 6 13.1 Theprecisionofthistestmethodwastested
40、byseven(7)laboratoriesinreagentwater,condensate,wellwater,andnatural water. Three laboratories reported data from two operators.Although multiple injections were reportedly made, the report sheets that were provided allowed only for reporting single values. Thus, no single operator precision can be
41、calculated. 13.1.1 The overall precision of this test method, within its designated range for both reagent water and selected natural water matrices, varies with the quantity tested, as shown in Fig. 1. 13.1.2 Recovery and bias data for this test method are listed in Table 1. 13.2 These data may not
42、 apply to waters of other matrices; therefore, it is the responsibility of the analyst to ensure the validity of the test method in a particular matrix. 14. Quality Control 14.1 In order to be certain that analytical values obtained using this test method are valid and accurate within the condence l
43、imits of the test, the following QC procedures must be followed when running the test. 14.2 Calibration and Calibration Verication 14.2.1 When beginning use of this method, an initial calibration verication standard (CVS) should be used to verify the calibrationstandardsandacceptableinstrumentperfor
44、mance.Thisvericationshouldbeperformedoneachanalysisday.TheCVS is a solution of the method analyte of known concentration (mid-calibration range) used to fortify reagent water. If the determined CVSconcentrationsarenotwithin615%oftheknownvalue,theanalystshouldreanalyzetheCVS.Ifthevaluestillfallsoutsi
45、de acceptable limits, a new calibration curve is required that must be conrmed by a successful CVS before continuing with ongoing analyses. 6 Supporting data are available from ASTM Headquarters. Request RR:D19-1119. D138507 (2013) 1 314.2.2 One CVS should then be run with each sample batch (maximum
46、 of 20 samples) to verify the previously established calibration curves. If the determined analyte concentrations fall outside acceptable limits (615%) that analyte is judged out of control, and the source of the problem should be identied before continuing with ongoing analyses. 14.3 Initial Demons
47、tration of Laboratory Capability 14.3.1 The laboratory using this test should perform an initial demonstration of laboratory capability.Analyze seven replicates of an initial demonstration of performance (IDP) solution. The IDP solution contains method analytes of known concentration, prepared from
48、a different source to the calibration standards, used to fortify reagent water. Ideally, the IPD solution should be prepared by an independent source from reference materials. The level 2 spiking solution used for the precision and bias study is a suitable IDP solution. The mean and standard deviati
49、on of the seven values should then be calculated and compared according to Practice D5847. 14.4 Laboratory Control Sample 14.4.1 One laboratory control sample (LCS) should be run with each sample batch (maximum of 20 samples). The LCS is a solution of method analytes of known concentration added to a matrix that sufficiently challenges the test method. A synthetic water matrix of relevance to the user (for example, drinking water or wastewater) spiked with the method analyte at the level of the IDPsolution wo
