1、Designation: D5622 95 (Reapproved 2011)D5622 16Standard Test Methods forDetermination of Total Oxygen in Gasoline and MethanolFuels by Reductive Pyrolysis1This standard is issued under the fixed designation D5622; the number immediately following the designation indicates the year oforiginal adoptio
2、n 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. Scope Scope*1.1 These test methods cover the quantitative determination of total oxy
3、gen in gasoline and methanol fuels by reductivepyrolysis.1.2 Precision data are provided for 1.01.0 % to 5.0 mass % oxygen 5.0 % oxygen by mass in gasoline and for 4040 % to 50mass % oxygen 50 % oxygen by mass in methanol fuels.1.3 Several types of instruments can be satisfactory for these test meth
4、ods. Instruments can differ in the way that theoxygen-containing species is detected and quantitated. However, these test methods are similar in that the fuel is pyrolyzed in acarbon-rich environment.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are
5、included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prio
6、r to use.2. Referenced Documents2.1 ASTM Standards:2D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Products byHydrometer MethodD4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density MeterD4057 Practice f
7、or Manual Sampling of Petroleum and Petroleum ProductsD4177 Practice for Automatic Sampling of Petroleum and Petroleum ProductsD4815 Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C1 to C4 Alcohols inGasoline by Gas Chromatography2.2 Other Standards:Clean Air Act
8、(1992)33. Summary of Test Method3.1 A fuel specimen of 11 L to 10 L 10 L is injected by syringe into a 950950 C to 1300C1300 C high-temperature tubefurnace that contains metallized carbon. Oxygen-containing compounds are pyrolyzed, and the oxygen is quantitatively convertedinto carbon monoxide.3.2 A
9、 carrier gas, such as nitrogen, helium, or a helium/hydrogen mixture, sweeps the pyrolysis gases into any of fourdownstream systems of reactors, scrubbers, separators, and detectors for the determination of the carbon monoxide content, henceof the oxygen in the original fuel sample. The result is re
10、ported as mass % oxygen in the fuel.4. Significance and Use4.1 These test methods cover the determination of total oxygen in gasoline and methanol fuels, and they complement TestMethod D4815, which covers the determination of several specific oxygen-containing compounds in gasoline.1 These test meth
11、ods are under the jurisdiction of Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and are the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved May 1, 2011June 1, 2016. Published August 2011June 2016. Originally approved in 1994. La
12、st previous edition approved in 20052011 asD562295(2005).D5622 95 (2011). DOI: 10.1520/D5622-95R11.10.1520/D5622-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to t
13、he standards Document Summary page on the ASTM website.3 Federal Register, Vol 57, No. 24, Feb. 5, 1992, p. 4408.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not
14、be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end
15、of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 The presence of oxygen-containing compounds in gasoline can promote more complete combustion, which reduces carbonmonoxide emissions. The Clean Air Act (1992) require
16、s that gasoline sold within certain, specified geographical areas contain aminimum percent of oxygen by mass (presently 2.7 mass %) during certain portions of the year. The requirement can be met byblending compounds such as methyl tertiary butyl ether, ethyl tertiary butyl ether, and ethanol into t
17、he gasoline.These test methodscover the quantitative determination of total oxygen which is the regulated parameter.4.2.1 Only seven U.S. states have such wintertime requirements, and others with EPA approval have opted out of the program.The minimum oxygen limit now varies from 1.8 % to 3.5 % by ma
18、ss. For methanol/heavier alcohol blend EPA waivers, themaximum oxygen content allowed is 3.5 % or 3.7 % by mass.4.2.1.1 Only ethanol is used for such blending in the U.S. Ethers are banned by some states and are not used in all states becauseof water contamination issues.5. Apparatus5.1 Oxygen Eleme
19、ntal Analyzer4,5,6,7,8A variety of instrumentation can be satisfactory. However, the instrument mustreductively pyrolize the specimen and convert oxygen to carbon monoxide.5.1.1 Test Method A4,8Helium carrier gas transports the pyrolysis products through a combination scrubber to remove acidicgases
20、and water vapor. The products are then transported to a molecular sieve gas chromatographic column where the carbonmonoxide is separated from the other pyrolysis products.Athermal conductivity detector generates a response that is proportionalto the amount of carbon monoxide.5.1.2 Test Method B5,8Ni
21、trogen carrier gas transports the pyrolysis products through a scrubber to remove water vapor. Thepyrolysis products then flow through tandem infrared detectors that measure carbon monoxide and carbon dioxide, respectively.5.1.3 Test Method C6,8Amixture of helium and hydrogen (95:5 %), helium, or ar
22、gon transports the pyrolysis products throughtwo reactors in series. The first reactor contains heated copper which removes sulfur-containing products. The second reactorcontains a scrubber which removes acidic gases and a reactant which oxidizes carbon monoxide to carbon dioxide (optional). Theprod
23、uct gases are then homogenized in a mixing chamber, which maintains the reaction products at absolute conditions oftemperature, pressure, and volume. The mixing chamber is subsequently depressurized through a column that separates carbonmonoxide (or carbon dioxide, if operating in the oxidation mode
24、) from interfering compounds. A thermal conductivity detectormeasures a response proportional to the amount of carbon monoxide or carbon dioxide.5.1.4 Test Method D7,8Nitrogen carrier gas transports the pyrolysis products through scrubbers to remove acidic gases andwater vapor. A reactor containing
25、cupric oxide at 325C325 C oxidizes the carbon monoxide to carbon dioxide, which in turn istransported into a coulometric carbon dioxide detector. Coulometrically generated base titrates the acid formed by reacting carbondioxide with monoethanolamine.5.2 A technique must be established to make a quan
26、titative introduction of the test specimen into the analyzer. Specimen vialsand transfer labware must be clean and dry.5.3 For instruments that measure carbon monoxide only, pyrolysis conditions must be established to quantitatively convertoxygen to carbon monoxide.5.4 A system of scrubbers and sepa
27、rators must be established to effectively remove pyrolysis products that interfere with thedetection of carbon monoxide or carbon dioxide, or both.5.5 The detector responses must be linear with respect to concentration, or nonlinear responses must be detectable andaccurately related to concentration
28、.5.6 Selected items are available from the instrument manufacturer.5.6.1 Pyrolysis tubes,5.6.2 Scrubber tubes, and5.6.3 Absorber Tubes.6. Reagents6.1 Purity of Reagents9Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents conform to the spec
29、ifications of the Committee on Analytical Reagents of the American Chemical Society where such4 The sole source of supply of the apparatus (Thermo Scientific formerly known as Carlo Erba Models 1108, 1110, now FLASH 1112 and FLASH 2000) known to thecommittee at this time is CE Elantech, Inc., 170 Ob
30、erlin Ave. N., Ste 5, Lakewood, NJ 08701.5 The sole source of supply of the apparatus (Leco Model RO-478) known to the committee at this time is Leco Corp., 3000 Lakeview Ave., St. Joseph, MI 49085.6 The sole source of supply of the apparatus (Perkin-Elmer Series 2400) known to the committee at this
31、 time is Perkin-Elmer Corp., 761 Main Ave., Norwalk, CT 06859.7 The sole source of supply of the apparatus (UIC, Inc./Coulometrics Model 5012 CO2 coulometer and Model 5220 autosampler-furnace) known to the committee at thistime is UIC Inc., Box 863, Joliet, IL 60434.8 If you are aware of alternative
32、 suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1 which you may attend.9 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washing
33、ton, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.D5622 162s
34、pecifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of the determination.6.2 Calibration Standards:6.2.1 NIST SRM 1837,10which contains certified concentrations of meth
35、anol and t-butanol in reference fuel, can be used tocalibrate the instrument for the analysis of oxygenates in gasoline.6.2.2 Anhydrous methanol, 99.8 % minimum assay, can be used to calibrate the instrument for the analysis of methanol fuels.6.2.3 Isooctane, or other hydrocarbons, can be used as th
36、e blank provided the purity is satisfactory.6.3 Quality Control StandardNIST SRM 183810 can be used to check the accuracy of the calibration.6.4 The instrument manufacturers require additional reagents.6.4.1 Test Method A: 4,86.4.1.1 Anhydrone (anhydrous magnesium perchlorate),6.4.1.2 Ascarite II (s
37、odium hydroxide on silica),6.4.1.3 Helium carrier gas, 99.995 % pure,6.4.1.4 Molecular sieve, 5, 60 to 80 mesh,6.4.1.5 Nickel wool,6.4.1.6 Nickelized carbon, 20 % loading,6.4.1.7 Quartz chips, and6.4.1.8 Quartz wool.6.4.2 Test Method B:5,86.4.2.1 Anhydrone (anhydrous magnesium perchlorate),6.4.2.2 C
38、arbon pyrolysis pellets, and6.4.2.3 Nitrogen carrier gas, 99.99 % pure.6.4.3 Test Method C:6,86.4.3.1 Anhydrone (anhydrous magnesium perchlorate),6.4.3.2 Ascarite II (sodium hydroxide on silica),6.4.3.3 Carrier gas, either helium (95 %)hydrogen (5 %), mixture, 99.99 % pure; helium, 99.995 % pure; or
39、 argon, 99.98 %pure,6.4.3.4 Copper plus, wire form, and6.4.3.5 Platinized carbon.6.4.4 Test Method D:7,86.4.4.1 Anhydrone (anhydrous magnesium perchlorate),6.4.4.2 Ascarite II (sodium hydroxide on silica),6.4.4.3 Copper (II) oxide,6.4.4.4 Coulometric cell solutions, including a cathode solution of m
40、onoethanolamine in dimethyl sulfoxide and an anodesolution of water and potassium iodide in dimethyl sulfoxide,6.4.4.5 Nickelized carbon, 20 % loading, and6.4.4.6 Nitrogen carrier gas, 99.99 % pure.7. Sampling7.1 Take samples in accordance with the instructions in PracticePractices D4057 or D4177.7.
41、2 Visually inspect the samples, and when there is evidence of nonuniformity, take fresh samples.7.3 Store the samples in a cold room or a laboratory refrigerator designed for storage of chemicals.8. Preparation of Apparatus8.1 Prepare the instrument in accordance with the manufacturers recommendatio
42、ns. These test methods require that correctoperating procedures are followed for the model used. Instrument design differences make it impractical to specify all of therequired operating conditions.8.2 The carrier gas can be scrubbed to remove traces of oxygen and oxygen-containing compounds.9. Cali
43、bration and Standardization9.1 Calibration for Test Methods A, B, and C, Oxygenates in Gasoline:9.1.1 Use a syringe to introduce 11 L to 10 L, 10 L, or 11 mg to 10 mg, 10 mg, of the blank. The amount of specimen mustbe precisely known. Measure the response. Repeat the introduction and measurement un
44、til stable readings are observed.10 Available from the National Institute of Standards and Technology, Gaithersburg, MD 20899.D5622 1639.1.2 In similar fashion, introduce 11 L to 10 L, 10 L, or 11 mg to 10 mg, 10 mg, of SRM 183710 and measure the response.Repeat two times with the same quantity of t
45、he SRM. If the blank corrected responses do not agree within 2 % relative, takecorrective action and repeat the calibration.9.1.3 Calculate the K-factor as follows:K 5Cstd 3MstdRavg(1)where:C std = mass % oxygen in the SRM,Mstd = mass of the SRM, mg,= volume of the SRM (L) density of the SRM (g/mL),
46、 andRavg = average of the blank corrected responses.NOTE 1Density can be determined by Test Method D1298 or Test Method D4052.9.2 Calibration for Test Methods A, B, and C, Methanol FuelsRepeat procedure 9.1; however, substitute anhydrous methanolfor the SRM. For methanol fuels, a unique K-factor can
47、 be necessary.9.3 Calibration for Test Method DThis test method does not require calibration; however, a quality control standard must beanalyzed to ensure proper operation of the instrument. A blank must also be analyzed periodically to ensure consistent responses.9.4 Quality Control (QC):9.4.1 Int
48、roduce the QC standard SRM 183810 in the same manner as the calibration standards. Calculate the percent oxygen(m/m) as described in Section 10.9.4.2 When results obtained on the QC standard do not agree with the certified values within 2 % relative, take corrective actionand repeat the calibration
49、and quality control.9.4.3 For Test Method D, when the recovery of oxygen from the QC SRM is less than 0.85 (that is, 85 %), take corrective actionand repeat the quality control. Recoveries that are greater than 0.85 but less than unity can be used to correct the calculated result(refer to the r parameter in Section 10).9.5 Procedure:9.5.1 Introduce the samples, and record the instrument response. Calculate the results as described in Section 10. Use theappropriate K-factor for oxygenates in gasoline and methanol fuels.9.5.2 Recalibrate the instrume
