1、Designation: D1385 07 (Reapproved 2018)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.1NOTEWarning notes were editorially updated throughout and the Keywords s
3、ection was added in August 2018.1. 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 rang
4、e is for photometric measurements 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 usersresponsibility to ensure the validity of thistest method for untested types of waters.1.3 The values stated in SI units are to be
5、 regarded asstandard. No other 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, health, and environmental
6、practices and deter-mine the applicability of regulatory limitations prior to use.For specific precautionary statements, see 5.3, 8.4, and Foot-note 5.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decisi
7、on on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1193 Specifica
8、tion for Reagent WaterD3370 Practices for Sampling Water from Closed 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 Spectrophot
9、ometryE275 Practice for Describing and Measuring Performance ofUltraviolet and Visible Spectrophotometers3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer toTerminology D1129.4. Summary of Test Method4.1 When a solution of p-dimethylaminobenzaldehyde inmethyl
10、alcohol and hydrochloric acid is added to hydrazine indiluted hydrochloric 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)
11、 hydrazine.5. Significance and Use5.1 Hydrazine is a man-made chemical and 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 preven
12、t corrosion by dissolved oxy-gen. This reducing chemical reacts with dissolved oxygen toform nitrogen and water. However, under certain conditions it1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the responsibility of Subcommittee D19.03 on Sampling Water andWater-F
13、ormed Deposits, Analysis of Water for Power Generation and Process Use,On-Line Water Analysis, and Surveillance of WaterCurrent edition approved Aug. 1, 2018. Published September 2018. Originallyapproved in 1967. Last previous edition approved in 2013 as D1385 07 (2013)1.DOI: 10.1520/D1385-07R18E01.
14、2For further information on this test method, the following references may be ofinterest:Watt, G. W., and Chrisp, J. D., “Spectrophotometric Method for the Determinationof Hydrazine,” Analytical Chemistry, Vol 24, No. 12, 1952, pp. 20062008; andWood, P. R., “Determination of Maleic Hydrazide Residue
15、s in Plant and AnimalTissue,” Analytical Chemistry, Vol 25, No. 12, 1953, pp. 18791883.3For 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 Summar
16、y page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles f
17、or theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1can also decompose to form ammonia and nitrogen. Hydrazineis used extensively as a preboiler treatment chemical forhigh-pressure boilers to sca
18、venge small amounts of dissolvedoxygen that are not removed by mechanical aeration. 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 prot
19、ection of idle boilers, hydrazine may bepresent in concentrations as high as 200 mg/L.5.2 Additionally, 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
20、 a thresholdlimit value in the atmosphere of 1.0 mg/L has been set byOSHA. When in an aqueous solution, 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 wit
21、h the test; however, the hydrazine content maybe diminished by oxidizing agents, such as chlorine, 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.
22、3 Aromatic amines, such as aniline, will also interfere.7. Apparatus7.1 PhotometerAspectrophotometer 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 to
23、Practice E60, and spectrophotometers to Practice E275.7.2 Certain photoelectric filter photometers 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
24、 in direct concentration can alsobe used. Manufacturers instructions should be followed.8. Reagents8.1 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
25、Reagents of the American Chemical Society,where such specifications are available.4Other grades may 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 indica
26、ted, referencesto water shall be understood to mean reagent water conformingto the quantitative requirements 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
27、 HCl (sp gr 1.19).Dilute with water to 1 L in a volumetric flask and mix.(WarningSee 8.4.)8.4 Hydrazine Solution, Standard (1.0 mL = 0.500 gN2H4)Dilute 5.0 mL of hydrazine stock solution to 1 L withwater and mix. Prepare as needed. (WarningHydrazine is asuspected carcinogen and should be handled wit
28、h care.5)8.5 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).8.6 p-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. Sampl
29、ing9.1 Collect the sample in accordance with Practices D3370or Practice D1066, whichever is applicable. (WarningSee8.4.)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
30、anddiluting to 100 mL. Prepare a blank with water at the sametime.9.3 A smaller sample 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 ofhy
31、drazine standard solution (1.0 mL = 0.500 g N2H4) into500-mL volumetric flasks. Add 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
32、 of the hydrazine standardsolutions into clean, dry 100-mL beakers or flasks and proceedas 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 re
33、ads out in directconcentrations.10.3 A separate calibration curve must be made for 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 each4Reagent Chemicals, America
34、n 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 Formulary, U
35、.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.5MacEwen, J. D., Vernot, E. H., Haun, C. C., and Kinkead, E. B., “ChronicInhalation Toxicity of Hydrazine: Onconogenic Effects,” in cooperation with theUniversity of California (Irvine) and the Airforce Aero Medical Research Labora-tory.D1385 0
36、7 (2018)12series of tests by running two or more solutions of knownhydrazine concentrations.11. Procedure11.1 Pipet 50.0 mL of the blank, standard solutions, andacidified diluted sample solutions into clean, dry 100-mLbeakers or flasks.11.2 Add 10.0 mL of p-dimethylaminobenzaldehyde solu-tion with a
37、 pipet to each beaker or flask and mix well.11.3 After a minimum of 10 min, but no 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 instr
38、ument may be calibrated with the stan-dard solutions to read directly in concentration 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. C
39、alculation12.1 Calculate the concentration of hydrazine in micro-grams per litre (parts per billion) in the sample by applying thefollowing equation for the hydrazine determined in 11.4:hydrazine N2H4!, g/L ppb! 5 AB/C (1)where:A = hydrazine indicated by the calibration curve or readdirectly from th
40、e instrument, g/L,B = volume of the flask, g/L, in which the sample wasdiluted in 9.2, mL, andC = volume of the sample in 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 labora
41、tories reported data from twooperators. Although multiple injections were 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
42、 both reagent water and selected naturalwater matrices, varies with the 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 th
43、evalidity of the test method in a particular matrix.14. Quality Control14.1 In order to be certain that analytical values obtainedusing this test method are valid and accurate within theconfidence limits of the test, the following quality control (QC)procedures must be followed when running the test
44、.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 thecalibration standards and acceptable instrument performance.This verification should be performed on each analysis day.6Supporting
45、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 Precision for HydrazineD1385 07 (2018)13The CVS is a solution of the method analyte of knownconcentration (mid-calibration range
46、) used to fortify reagentwater. If the determined CVS concentrations are not within615 % of the 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 on
47、going analyses.14.2.2 One CVS should then be run with each sample batch(maximum of 20 samples) 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 sh
48、ould be identifiedbefore continuing with ongoing analyses.14.3 Initial Demonstration of Laboratory 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 I
49、DP solution contains method analytes of knownconcentration, prepared from a different source 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 should then becalculated and compared according to Practice D5847.14.4 Laboratory Control Sample:14.4.1 One laboratory control sample (LCS) should be run
