1、Designation: D1385 07 (Reapproved 2013)1Standard Test Method forHydrazine in Water1This standard is issued under the fixed designation D1385; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1NOTEThis standard was reapproved with editorial changes in January 2013.
3、1. Scope1.1 This test method covers2the colorimetric determinationof hydrazine in boiler feed waters, condensates, natural, andwell waters that have been treated with hydrazine (N2H4). Thistest method is usable in the range from 5.0 to 200 g/L (ppb)hydrazine. The range is for photometric measurement
4、s made at458 nm in 50 mm cell. Higher concentrations of hydrazine canalso be determined by taking a more diluted sample.1.2 It is the users responsibility to ensure the validity of thistest method for untested types of waters.1.3 The values stated in SI units are to be regarded asstandard. No other
5、units of measurement are included in thisstandard.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 r
6、egulatory limitations prior to use. For specificprecautionary statements, see 5.3, Note 1, and Footnote 8.2. Referenced Documents2.1 ASTM Standards:3D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD3370 Practices for Sampling Water from Closed
7、 ConduitsD5810 Guide for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water AnalysisE60 Practice for Analysis of Metals, Ores, and RelatedMaterials by SpectrophotometryE275 Practice for Describing and Measuring Performance ofUltra
8、violet and Visible Spectrophotometers3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology D1129.4. Summary of Test Method4.1 When a solution of p-dimethylaminobenzaldehyde inmethyl alcohol and hydrochloric acid is added to hydrazine indiluted hydrochlor
9、ic acid solution, a characteristic yellow colorof p-dimethylaminobenzalazine is formed. The yellow colorformed is proportional to the hydrazine present and is in goodagreement with Beers law in the range from 5.0 to 200 g/L(ppb) hydrazine.5. Significance and Use5.1 Hydrazine is a man-made chemical a
10、nd is not found innatural waters. The determination of hydrazine is usually madeon boiler feedwaters, process waters, and other waters thathave been treated with hydrazine (N2H4) for the purpose ofmaintaining residuals to prevent corrosion by dissolved oxy-gen. This reducing chemical reacts with dis
11、solved oxygen toform nitrogen and water. However, under certain conditions itcan also decompose to form ammonia and nitrogen. Hydrazineis used extensively as a preboiler treatment chemical forhigh-pressure boilers to scavenge small amounts of dissolvedoxygen that are not removed by mechanical aerati
12、on. It has theadvantage over sulfite treatment in that it does not produce anydissolved solids in the boiler water. Hydrazine is often deter-mined in concentrations below 0.1 mg/L. However, in layupsolutions for the protection of idle boilers, hydrazine may bepresent in concentrations as high as 200
13、 mg/L.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the responsibility of Subcommittee D19.03 on Sampling Water andWater-Formed Deposits, Analysis of Water for Power Generation and Process Use,On-Line Water Analysis, and Surveillance of WaterCurrent edition approve
14、d Jan. 1, 2013. Published February 2013. Originallyapproved in 1967. Last previous edition approved in 2007 as D1385 07. DOI:10.1520/D1385-07R13E01.2For further information on this test method, the following references may be ofinterest: Watt, G. W., and Chrisp, J. D., “Spectrophotometric Method for
15、 theDetermination of Hydrazine,” Analytical Chemistry, Vol 24, No. 12, 1952, pp.20062008, and Wood, P. R., “Determination of Maleic Hydrazide Residues in Plantand Animal Tissue,” Analytical Chemistry, Vol 25, No. 12, 1953, pp. 18791883.3For referenced ASTM standards, visit the ASTM website, www.astm
16、.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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 Additio
17、nally, hydrazine provides protection where re-ducing conditions are required, particularly in mixed metal-lurgy systems for the protection of the copper alloys.5.3 Hydrazine is a suspected carcinogen and a thresholdlimit value in the atmosphere of 1.0 mg/L has been set byOSHA. When in an aqueous sol
18、ution, hydrazine will oxidize tonitrogen and water in the presence of air over a relatively shortperiod of time.6. Interferences6.1 The substances normally present in industrial water donot interfere with the test; however, the hydrazine content maybe diminished by oxidizing agents, such as chlorine
19、, bromine,and iodine, collected with the sample or absorbed by it prior totesting.6.2 Colors in the prescribed wavelengths also interfere, asdo other dark colors or turbidities that cannot be overcome.6.3 Aromatic amines, such as aniline, will also interfere.7. Apparatus7.1 PhotometerAspectrophotome
20、ter suitable for measure-ments at 458 nm and capable of holding cells with a light pathof 50 mm should be used. Filter photometers and photometricpractices prescribed in this test method shall conform toPractice E60, and spectrophotometers to Practice E275.7.2 Certain photoelectric filter photometer
21、s are capable ofmeasurement at 425 nm, but not at 458 nm. Measurements maybe made at 425 nm with a reduction in sensitivity of approxi-mately 50 % of that possible at 458 nm.7.3 Instruments that read out in direct concentration can alsobe used. Manufacturers instructions should be followed.8. Reagen
22、ts8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.4Other grades m
23、ay beused, provided it is first ascertained that the reagent issufficiently high in purity to permit its use without lesseningthe accuracy of the determinations.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto the quantitative r
24、equirements of Type III reagent water inSpecification D1193.8.3 Hydrazine Solution, Stock (1.0 mL = 100 g N2H4)Dissolve 0.328 g of hydrazine dihydrochloride (HClNH2NH2HCl) in 100 mL of water and 10 mL of HCl (sp gr 1.19).Dilute with water to 1 L in a volumetric flask and mix(Warning, see Note 1).8.4
25、 Hydrazine Solution, Standard (1.0 mL = 0.500 g N2H4)Dilute 5.0 mL of hydrazine stock solution to 1 L with waterand mix. Prepare as needed.NOTE 1Warning: Hydrazine is a suspected carcinogen and should behandled with care.58.5 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).8.6 p-
26、Dimethylaminobenzaldehyde SolutionDissolve 4.0g of p-dimethylaminobenzaldehyde (CH3)2NC6H4CHO in200 mL of methyl alcohol (CH3OH) and 20 mL of HCl (sp gr1.19). Store in a dark bottle out of direct sunlight.9. Sampling9.1 Collect the sample in accordance with Practices D3370or Practice D1066, whicheve
27、r is applicable (Warning, seeNote 1).9.2 Acidify and dilute the sample as soon as taken by adding1 mL of concentrated HCl (sp gr 1.19) to a 100-mL volumetricflask and then pipetting 50 mL of the sample into the flask anddiluting to 100 mL. Prepare a blank with water at the sametime.9.3 A smaller sam
28、ple aliquot should be taken if the hydra-zine concentration is greater than 200 g/L.10. Calibration10.1 Prepare a series of standard hydrazine solutions bypipetting 0.0, 5.0, 10.0, 25.0, 50.0, 100.0, and 200.0 mL ofhydrazine standard solution (1.0 mL = 0.500 g N2H4) into500-mL volumetric flasks. Add
29、 5 mL of HCl (sp gr 1.19) toeach flask and dilute with water to 500 mL and mix well. Thiswill give standard solutions containing 0, 5.0, 10.0, 25.0, 50.0,100, and 200 g/L (ppb) of hydrazine.10.2 Pipet 50.0-mL portions of the hydrazine standardsolutions into clean, dry 100-mL beakers or flasks and pr
30、oceedas directed in 11.2. Plot absorbance on the ordinate andmicrograms per litre of hydrazine on the abscissa of lineargraph paper. Alternately, graph the data in an electronicspreadsheet or use an instrument that reads out in directconcentrations.10.3 A separate calibration curve must be made for
31、eachphotometer and a recalibration must be made if it is necessaryto change the cell, lamp, or filter, or if any other alterations ofinstrument or reagents are made. Check the curve for eachseries of tests by running two or more solutions of knownhydrazine concentrations.11. Procedure11.1 Pipet 50.0
32、 mL of the blank, standard solutions, andacidified diluted sample solutions into clean, dry 100-mLbeakers or flasks.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical So
33、ciety, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.5MacEwen, J. D., Vernot, E. H., Haun, C. C., and Kinkead, E. B., “ChronicInhalation Toxicity of Hydra
34、zine: Onconogenic Effects,” in cooperation with theUniversity of California (Irvine) and the Airforce Aero Medical Research Labora-tory.D1385 07 (2013)1211.2 Add 10.0 mL of p-dimethylaminobenzaldehyde solu-tion with a pipet to each beaker or flask and mix well.11.3 After a minimum of 10 min, but no
35、longer than 100min, measure the color absorbance of each solution at 458 nmin a 50 mm cell with a spectrophotometer, using the blank asreference solution for the initial instrument setting at zeroabsorbance. The instrument may be calibrated with the stan-dard solutions to read directly in concentrat
36、ion if such capa-bilities are available.11.4 Determine the micrograms per litre of hydrazine byreferring the absorbance obtained for the sample to thecalibration curve or reading hydrazine concentration directly.12. Calculation12.1 Calculate the concentration of hydrazine in micro-grams per litre (p
37、arts per billion) in the sample by applying thefollowing equation for the hydrazine determined in 11.4:hydrazine N2H4!, g/L ppb! 5 AB/Cwhere:A = hydrazine indicated by the calibration curve or readdirectly from the instrument, g/L,B = volume of the flask, g/L, in which the sample wasdiluted in Secti
38、on 9.2, mL, andC = volume of the sample in Section 9.2, mL.13. Precision and Bias613.1 The precision of this test method was tested by seven(7) laboratories in reagent water, condensate, well water, andnatural water. Three laboratories reported data from twooperators. Although multiple injections we
39、re reportedly made,the report sheets that were provided allowed only for reportingsingle values. Thus, no single operator precision can becalculated.13.1.1 The overall precision of this test method, within itsdesignated range for both reagent water and selected naturalwater matrices, varies with the
40、 quantity tested, as shown in Fig.1.13.1.2 Recovery and bias data for this test method are listedin Table 1.13.2 These data may not apply to waters of other matrices;therefore, it is the responsibility of the analyst to ensure thevalidity of the test method in a particular matrix.14. Quality Control
41、14.1 In order to be certain that analytical values obtainedusing this test method are valid and accurate within the6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D19-1119. ContactASTM CustomerService at serviceastm.org.FIG. 1 P
42、recision for HydrazineTABLE 1 Recovery and BiasAmountAdded,g/LAmountFound,g/L% BiasStatisticallySignificant,%(95%ConfidenceLevel)Reagent Water Type II6.041 5.891 2.5 No51.57 51.54 0.1 No177.8 178.1 0.2 No112.9 113.2 0.3 NoSelected Water Matrices6.041 5.935 1.7 No51.57 50.77 1.6 No177.8 176.2 0.9 Yes
43、112.9 111.2 1.5 NoD1385 07 (2013)13confidence limits of the test, the following QC procedures mustbe followed when running the test.14.2 Calibration and Calibration Verification:14.2.1 When beginning use of this method, an initial cali-bration verification standard (CVS) should be used to verify the
44、calibration standards and acceptable instrument performance.This verification should be performed on each analysis day.The CVS is a solution of the method analyte of knownconcentration (mid-calibration range) used to fortify reagentwater. If the determined CVS concentrations are not within615 % of t
45、he known value, the analyst should reanalyze theCVS. If the value still falls outside acceptable limits, a newcalibration curve is required that must be confirmed by asuccessful CVS before continuing with ongoing analyses.14.2.2 One CVS should then be run with each sample batch(maximum of 20 samples
46、) to verify the previously establishedcalibration curves. If the determined analyte concentrations falloutside acceptable limits (615 %) that analyte is judged out ofcontrol, and the source of the problem should be identifiedbefore continuing with ongoing analyses.14.3 Initial Demonstration of Labor
47、atory Capability:14.3.1 The laboratory using this test should perform aninitial demonstration of laboratory capability. Analyze sevenreplicates of an initial demonstration of performance (IDP)solution. The IDP solution contains method analytes of knownconcentration, prepared from a different source
48、to the calibra-tion standards, used to fortify reagent water. Ideally, the IPDsolution should be prepared by an independent source fromreference materials. The level 2 spiking solution used for theprecision and bias study is a suitable IDP solution. The meanand standard deviation of the seven values
49、 should then becalculated and compared according to Practice D5847.14.4 Laboratory Control Sample:14.4.1 One laboratory control sample (LCS) should be runwith each sample batch (maximum of 20 samples). The LCS isa solution of method analytes of known concentration added toa matrix that sufficiently challenges the test method. A syn-thetic “water” matrix of relevance to the user (for example,drinking water or wastewater) spiked with the method analyteat the level of the IDP solution would be an example of anappropriate LCS. The analyte
