ASTM_D_6505_-_00_2012.pdf

Designation:D650500(Reapproved 2012)Standard Test Method forAssay of normal-Propyl Bromide Content1This standard is issued under the fixed designation D6505;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 provides a basis for the determinationof the normal-propyl bromide(weight%)in the presence ofstabilizers and impurities,in virgin or reclaimed normal-propylbromide(nPB).The application range is from 50 to 100 wt%.2.Summary of Test Method2.1 This analytical test method describes the determinationof the assay of n-propyl bromide by gas chromatography usingan internal standard.The results are reported in weight percent.3.Significance and Use3.1 This test method provides an analysis in weight percentof the normal-propyl bromide concentration of virgin,formulated,or reclaimed normal-propyl bromide:compoundsthat co-elute with normal-propyl bromide or normal-heptane(internal standard)may interfere with this test method.4.Apparatus4.1 Gas ChromatographHewlett Packard 5890 Series IIequipped with a split/splitless injector,a flame ionizationdetector,and an autosampler,HP,or equivalent,if available.4.2 Column30 m by 0.25 mm,1.0-m film thicknessAllTech AT-5,or equivalent,capillary column.4.3 Syringe5-L or 10-L GC autosampler syringe.4.4 Data Acquisition and Analysis DeviceVAX MULTI-CHROM or equivalent chromatography data collection andprocessing system,or integrator.4.5 Crimp Top VialsHewlett Packard 2-mL glass crimptop vials with TFE-fluorocarbon-lined silicone septa or equiva-lent.4.6 Volumetric Pipet25 mL.4.7 Glass Vials32mL glass vials(25 by 95 mm),withTFE-fluorocarbon-lined screw caps.4.8 Transfer PipetsBorosilicate glass transfer pipets.4.9 Precision Balance,accurate to 0.1 mg.5.Required Chemicals5.1 n-Propyl Bromide(1-Bromopropane),99+%,AldrichChemical Company5.2 n-Heptane(internal standard),Reagent Grade,99.5+%,J.T.Baker(or equivalent)5.3 Methylene Chloride,99+%,Aldrich Chemical Com-pany(or equivalent)6.Suggested Analysis Conditions6.1 Chromatographic Conditions:Injector150CDetector temperature250CFID detector rangemost sensitive settingTemperatureprogram30C for 10 min30 to 250C at 15C/minhold at 250C for 10 minCarrier gasHe(or N2)at 1 mL/minsplit flow:25 mL/mincolumn head pressure:7.5 psiMake-up gasHe(or N2)at 30 mL/minInjection volume0.5 L7.Analytical Procedure7.1 Internal Standard Calibration MixtureCarefullyweigh about 0.25 g of n-heptane internal standard and about0.5 g of n-propyl bromide into a 32-mL glass vial.Record theactual weights for each.Pipet 25 mLof methylene chloride intothis vial and cap immediately.Mix well and then transferapproximately 1 mL of this standard solution into an autosam-pler vial.Cap the vial and analyze in accordance with theconditions specified in the chromatographic conditions section.Inject this standard at least three times and calibrate an internalstandard method in the data system using the results from thestandard analyses.7.2 Preparation of Samples for AnalysisWeigh about 0.25g of n-heptane and about 0.5 g of sample into a 32-mL glassvial.Record the actual weights for each.Pipet 25 mL ofmethylene chloride into this vial and cap immediately.Mixwell and transfer approximately 1 mL of this solution to an1This test method is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility of Subcommittee D26.04 on Test Methods.Current edition approved March 1,2012.Published June 2012.Originallypublished in 2000.Last previous edition approved in 2006 as D650500(2006).DOI:10.1520/D6505-00R12.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 autosampler vial.Cap the vial and analyze in accordance withthe conditions specified in the chromatographic conditionssection.The following table shows components of interest,their absolute retention time(ART)in minutes,their relativeretention time(RRT)in relation to n-heptane,the internalstandard,as well as their relative response factor(RRf).ComponentARTRRTRRfn-propyl bromide13.300.830.3495n-heptane(internal standard)16.081.001.00008.Calculation8.1 A calibrated internal standard weight percent method inthe data system will yield the required weight percent data.Alternatively,the weight percent calculations may be per-formed manually as described as follows:8.2 Calculate the relative response factor(RRf)for n-propylbromide in the standard relative to the n-heptane internalstandard.Average the peak areas of the three standard injec-tions:RRf5Ay3WtlWty3Al(1)where:Ay=average area of n-propyl bromide peak in standardcalibration mixture,Al=average area of n-heptane(internal standard)peak instandard calibration mixture,Wty=amount of n-propyl bro