ASTM_D_5176_-_08_2015.pdf

Designation:D517608(Reapproved 2015)Standard Test Method forTotal Chemically Bound Nitrogen in Water by Pyrolysis andChemiluminescence Detection1This standard is issued under the fixed designation D5176;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the totalnitrogen content of water in concentrations from 0.5 to 1000mg/L.Higher nitrogen concentrations may be determined bymaking the proper dilutions.1.2 This test method does not determine molecular nitrogen(N2).1.3 The values stated in SI units are to be 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this standard,refer toTerminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 total chemically bound nitrogen,nall inorganic andorganic nitrogen in the sample,except molecular nitrogen(N2).4.Summary of Test Method4.1 The sample of water is introduced into a stream ofoxygen or inert/oxygen mix flowing through a quartz pyrolysistube.Oxidative pyrolysis converts chemically bound nitrogento nitric oxide(NO).The gas stream is dried and the NO iscontacted with ozone(O3)producing metastable nitrogendioxide(NO2*).As the NO2*decays,light is emitted anddetected by a photomultiplier tube.The resulting signal is ameasure of the total chemically bound nitrogen in the sample.5.Significance and Use5.1 This test method is useful for the determination of totalchemically bound nitrogen in wastewaters and other waters.6.Apparatus36.1 Pyrolysis FurnaceAn electric tube furnace capable ofachieving a temperature of 1100C.The furnace may be singleor multizoned and may have common or separate and inde-pendent temperature controls.6.2 Pyrolysis TubeThe pyrolysis tube must be fabricatedfrom quartz and should be designed to ensure completepyrolysis of a wide variety of samples.6.3 Chemiluminescence DetectorThe detector shall have aphotomultiplier tube capable of sensing the light emission ofthe decaying NO2*.The detector shall have digital display,onboard ozone generator and analog output for data system orstrip chart recorder.6.4 Recorder(optional)The recorder shall be able toaccept a 1 V full scale signal and to provide a chart speed of 1cm/min.6.5 Microlitre SyringeAny standard series of microlitresyringes with stainless steel needles is acceptable.See manu-facturers instructions for appropriate syringe sizes.6.6 Syringe Drive MechanismThe syringe drive shall becapable of driving the sample from a microlitre syringe at acontrolled,reproducible rate.1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct responsibility of Subcommittee D19.06 on Methods forAnalysis forOrganic Substances in Water.Current edition approved June 15,2015.Published June 2015.Originallyapproved in 1991.Last previous edition approved in 2008 as D5176 08.DOI:10.1520/D5176-08R15.2For 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 Summary page onthe ASTM website.3The apparatus described in 6.1 6.7 is manufactured by Antek Instruments,Inc.,Houston,TX and Dohrmann Division of Rosemount Analytical Inc.,SantaClara,CA,and was used in the validation study of this test method.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.7 Sample BoatSamples with high concentrations ofsuspended matter or dissolved nonvolatile compounds maytend to plug the syringe needle upon injection into the pyrolysistube.In this case a sample boat of quartz or platinum,with orwithout quartz wool,should be used,in conjunction with theappropriate pyrolysis tube.The pyrolysis tube shall allow theintroduction of the sample into the boat by microlitre syringewithout interrupting the gas flow system.7.Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused.Unless otherwise indicated,it is intended that all reagentsshall conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society.4Other grades may be used,provided it is first determined that