1、Designation: D5501 09D5501 12Standard Test Method forDetermination of Ethanol Content of Denatured Fuel andMethanol Content in Fuels Containing Greater than 20%Ethanol by Gas Chromatography1This standard is issued under the fixed designation D5501; the number immediately following the designation in
2、dicates 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. Scope*1.1 This test method covers the determinati
3、on of the ethanol content of denatured fuel ethanol by gas chromatography.1.1 Ethanol is determined from 93 to 97 mass % and methanol is determined from 0.01 to 0.6 mass %. Equations used to convertthese individual alcohols from mass % to volume % are provided.This test method covers the determinati
4、on of the ethanol contentof hydrocarbon blends containing greater than 20% ethanol. This method is applicable to denatured fuel ethanol, ethanol fuelblends, and mid-level ethanol blends.1.1.1 Ethanol is determined from 20 mass% to 100 mass% and methanol is determined from 0.01 mass% to 0.6 mass%.Equ
5、ations used to convert these individual alcohols from mass% to volume% are provided.NOTE 1Fuels containing less than 20% ethanol may be quantified using Test Method D5599, and less than 12% ethanol may be quantified using TestMethod D4815.1.2 This test method does identify and quantify methanol but
6、does not purport to identify all individual components commonto ethanol production or those components that make up the denaturant.denaturant or hydrocarbon constituent of the fuel.1.3 Water cannot be determined by this test method and shall be measured by a procedure such as Test Method D1364 and t
7、heresult used to correct the chromatographic values.concentrations determined by this method.1.4 This test method is inappropriate for impurities that boil at temperatures higher than 225C or for impurities that cause pooror no response in a flame ionization detector, such as water.1.5 The values st
8、ated in SI units are to be regarded as standard. No other units of measurement are included in this standard.thestandard. The values given in parentheses are provided for information purposes only.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its u
9、se. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1298 Test Method for Density, Relative Density, or API Gravity of Crude Petr
10、oleum and Liquid Petroleum Products byHydrometer MethodD1364 Test Method for Water in Volatile Solvents (Karl Fischer Reagent Titration Method)D4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density MeterD4057 Practice for Manual Sampling of Petroleum and Petro
11、leum ProductsD4175 Terminology Relating to Petroleum, Petroleum Products, and LubricantsD4307 Practice for Preparation of Liquid Blends for Use as Analytical StandardsD4626 Practice for Calculation of Gas Chromatographic Response FactorsD4806 Specification for Denatured Fuel Ethanol for Blending wit
12、h Gasolines for Use asAutomotive Spark-Ignition Engine Fuel1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.04.0Lon Hydrocarbon Analysis.Current edition approved April 15, 2009Nov. 1, 2012. Pu
13、blished May 2009March 2013. Originally approved in 1994. Last previous edition approved in 20042009 asD550104.09. DOI: 10.1520/D5501-09.10.1520/D5501-12.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM St
14、andardsvolume information, refer to the standards Document Summary page on the ASTM website.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 be technically possib
15、le 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 of this standardCopyr
16、ight ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D4815 Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C1 to C4 Alcohols inGasoline by Gas ChromatographyD5599 Test Method for Determination of Oxygenates in
17、 Gasoline by Gas Chromatography and Oxygen Selective FlameIonization DetectionD5798 Specification for Ethanol Fuel Blends for Flexible-Fuel Automotive Spark-Ignition EnginesD6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-ment S
18、ystem PerformanceD6792 Practice for Quality System in Petroleum Products and Lubricants Testing LaboratoriesE203 Test Method for Water Using Volumetric Karl Fischer TitrationE355 Practice for Gas Chromatography Terms and RelationshipsE594 Practice for Testing Flame Ionization Detectors Used in Gas o
19、r Supercritical Fluid ChromatographyE1064 Test Method for Water in Organic Liquids by Coulometric Karl Fischer TitrationE1510 Practice for Installing Fused Silica Open Tubular Capillary Columns in Gas Chromatographs3. Terminology3.1 DefinitionsThis test method makes reference to many common gas chro
20、matographic procedures, terms, and relationships.Detailed definitions can be found in Terminology D4175, and Practices E355 and E594.3.2 Definitions:3.2.1 mass response factor (MRF), nconstant of proportionality that converts area to mass percent.3.2.2 relative mass response factor (RMRF), nmass res
21、ponse factor of a component divided by that of another component.3.2.2.1 DiscussionIn this test method, the mass response factors are relative to that of n-heptane.3.2.3 tangential skimming, nin gas chromatography, integration technique used when a “rider” peak elutes on the tail of aprimary peak.3.
22、2.3.1 DiscussionSince the majority of the area beneath the rider peak belongs to the primary peak, in tangential skimming the top of the primarypeak tail is used as the baseline of the rider peak, and the triangulated area beneath the rider peak is added to the primary peak.3.3 Abbreviations:3.3.1 M
23、RFmass response factor3.3.2 RMRFrelative mass response factor4. Summary of Test Method4.1 A representative aliquot of the fuel ethanol sample is introduced into a gas chromatograph equipped with a polydimeth-ylsiloxane bonded phase capillary column. Helium carrier Carrier gas transports the vaporize
24、d aliquot through the column wherethe components are separated by the chromatographic process. chromatographically separated in order of boiling pointtemperature. Components are sensed by a flame ionization detector as they elute from the column. The detector signal is processedby an electronic data
25、 acquisition system. The ethanol and methanol components are identified by comparing their retention timesto the ones identified by analyzing standards under identical conditions. The concentrations of all components are determined inmass percent area by normalization of the peak areas. After correc
26、tion for water content, results may be reported in mass percentor volume percent.5. Significance and Use5.1 Fuel ethanol is required to be denatured with gasoline in accordance with Specification D4806. State and federal lawsspecify the concentration of ethanol in gasoline blends. The determination
27、of the amount of denaturant is important to ensure theblended fuel complies with federal and state laws. This test method provides a method of determining the percentage of ethanol(purity) of the fuel ethanol that is blended into gasoline.in an ethanol-gasoline fuel blend over the range of 20 to 100
28、 mass% forcompliance with fuel specifications and federal or local fuel regulations.5.2 Ethanol content of denatured fuel ethanol for gasoline blending is required in accordance with Specification D4806.5.3 Ethanol content of ethanol fuel blends for flexible-fuel automotive spark-ignition engines is
29、 required in accordance withSpecification D5798.D5501 1226. Apparatus6.1 Gas Chromatograph, capable of operating at the conditions listed in Table 1. A heated flash vaporizing injector designedto provide a linear sample split injection (for example, 200:1) is required for proper sample introduction.
30、 Carrier gas controls shallbe of adequate precision to provide reproducible column flows and split ratios in order to maintain analytical integrity. Pressureand flow control devices and gauges shall be designed to attain the linear velocity required in the column used. A hydrogen flameionization det
31、ector with associated gas controls and electronics, designed for optimum response with open tubular columns, isrequired.6.2 Sample IntroductionManual or automatic Automatic liquid syringe sample injection to the splitting injector is employed.injector. Devices capable of 0.1 to 0.5 L injections are
32、suitable. It should be noted that inadequate splitter design, poor injectiontechnique, and overloading the column can result in poor resolution. Avoid overloading, particularly of the ethanol peak, andeliminate this condition during analysis.NOTE 2Inadequate splitter, poor injection technique, and o
33、verloading the column can result in poor resolution.Avoid overloading, particularly of theethanol peak, and eliminate this condition during analysis.6.3 ColumnThis The precision for this test method utilizes was developed utilizing a fused silica open tubular column withnon-polar polydimethylsiloxan
34、e bonded (cross-linked) phase internal coating. Any column with equivalent or better chromato-graphic efficiency efficiency, resolution, and selectivity to those described in 6.3.1 canmay be used.6.3.1 Open tubular column with a non-polar polydimethylsiloxane bonded (cross-linked) phase internal coa
35、ting, either 150 mby 0.25 mm with a 1.0 m film thickness, or 100 m by 0.25 mm with a 0.5 film thickness is required.have been found suitable.The 150 m column is recommended due to its higher resolution. Follow Practice E1510 for column installation.6.4 Electronic Data Acquisition SystemAny data acqu
36、isition and integration device used for quantification of these analysesmust meet or exceed these minimum requirements:6.4.1 Capacity for at least 80 peaks/analysis,6.4.2 Normalized percent calculation based on peak area and using response factors,6.4.3 Identification of individual components based
37、on retention time,6.4.4 Noise and spike rejection capability,6.4.5 Sampling rate for narrow (96 % ethanol, 0.1 % methanol and3.9 % n-heptane. Calculate the mass relative response factor according to Practice D4626.10.4.1 Absolute CalibrationEstablish the correction factor or equation that directly r
38、elates the peak area to the componentconcentration. If available, multi-point calibration is preferred.NOTE 1Excessive tailing and delayed elution may result from adsorption, dead volume, or damaged column.FIG. 3 Example of Poor ChromatographyFIG. 4 Sample Chromatogram of Calibration Mixture on 150
39、m ColumnD5501 12710.4.1.1 Single-pointCalculate the mass response factor (MRF) of ethanol in each calibration standard using Eq 2 accordingto Practice D4626. The average response factor determine at each concentration shall be used in the calibration. Repeat formethanol and heptane. Assign the hepta
40、ne response factor to any unknowns.MRF(i)5mass%(i)area(i) (2)where:NOTE 1The regression is linear with a correlation coefficient greater than 0.995 and the calibration curve passes within 3 mass% ethanol of the origin.FIG. 5 Calibration Linearity Checks are Shown Using Either Axis for Ethanol Conten
41、tTABLE 2 Recommended Matrix of Calibration Standards Rangingfrom 20 to 99 Mass%Mix 1 Mix 2 Mix 3 Mix 4 Mix 5Methanol, mass% 0.6 0.5 0.3 0.2 0.1Ethanol, mass% 20.0 50.0 75.0 90.0 99.4Heptane, mass% 10.0 10.0 10.0 4.0 0.5Hydrocarbon diluent,Amass%69.4 39.5 14.8 5.8 0.0AHydrocarbon diluent is free of h
42、eptane and any other compounds that wouldinterfere with the calibration. See 7.4.D5501 128MRF(i) = the mass response factor of component i,Mass%(i) = the mass percent of component i, andArea(i) = the peak area of component i.10.4.1.2 Multi-pointWith this technique, calibration and linearity verifica
43、tion may be completed in the same step.Analyze thestandards prepared in 10.2, according to the procedure in Section 12. Generate individual calibration curves for methanol, ethanol,and heptane following the software manufacturers instructions. Calibration curves shall be linear with a minimum r2 of
44、0.995.Verify that the calibration curve of ethanol passes near the origin (see Note 3), but do not force the origin. Force methanol andheptane calibrations through zero if necessary to quantify small peaks. Failure to quantify small unknown peaks will result inincorrect ethanol determination. The ca
45、libration equation of heptane shall be assigned to all unknowns.NOTE 3Software packages can differ in designation of the axes. If the peak area is on the x-axis, the y-intercept of the ethanol curve shall be between-3 and +3 mass%. If the peak area is on the y-axis, solving the calibration equation
46、for y = 0 shall give a result between -3 and +3 mass%.10.4.2 Relative CalibrationTabulate the mass response factors (MRF) of ethanol, methanol, and n-heptane according to Eq2. Then calculate the relative mass response factor (RMRF) of methanol and ethanol relative to heptane with Eq 3. Typical relat
47、ivemass response factors for the components of interest are found in Table 3.RMRF(i)5MRF(i)MRF(heptane) (3)where:RMRF(i) = the relative mass response factor of component i relative to n-C7,MRF(i) = the mass response factor of component i, andMRF(heptane) = the mass response factor of heptane.Average
48、 the experimental ethanol relative mass response factors determined for each standard. Use the average RMRF as thecalibration value. Repeat for methanol. Assign heptane and all unknowns an RMRF of 1.000.10.5 After completing the calibration, calculate the composition of each calibration standard acc
49、ording to the procedure inSection 13. Verify that the normalized results are in agreement with theoretical ethanol values within 60.5% and with theoreticalmethanol values within 60.05%.11. Quality Control11.1 Conduct a regular statistical quality assurance (quality control) program, monitoring both precision and accuracy, inaccordance with the techniques of Practice D6299 or equivalent. Measure the ethanol and methanol concentrations using theprocedure outlined in Section 12. Confirm the performance of the instrument or the test procedure after each c
