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ASTM E1747-95(2019)

(Guide)

Standard Guide for Purity of Carbon Dioxide Used in Supercritical Fluid Applications

Standard Guide for Purity of Carbon Dioxide Used in Supercritical Fluid Applications

ABSTRACT
This guide defines purity standards for carbon dioxide to ensure the suitability of liquefied carbon dioxide gas for use in supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC) applications. This guide defines quantitation, labeling, and statistical standards for impurities in carbon dioxide that are necessary for successful SFE or SFC laboratory work, and it suggests methods of analysis for quantifying these impurities. These contaminants are those components that either cause detector signals that interfere with those of the target analytes or physically impede the SFE or SFC experiment. Also, this guide is provided for use by specialty gas suppliers who manufacture carbon dioxide specifically for SFE or SFC applications. SFE or SFC CO2 products offered with a claim of adherence to this guide will meet certain absolute purity and contaminant detectability requirements matched to the needs of current SFE or SFC techniques.
SCOPE
1.1 This guide defines purity standards for carbon dioxide to ensure the suitability of liquefied carbon dioxide gas for use in SFE and SFC applications (see Guide E1449 for definitions of terms). This guide defines quantitation, labeling, and statistical standards for impurities in carbon dioxide that are necessary for successful SFE or SFC laboratory work, and it suggests methods of analysis for quantifying these impurities.  
1.2 This guide is provided for use by specialty gas suppliers who manufacture carbon dioxide specifically for SFE or SFC applications. SFE or SFC carbon dioxide (CO2) products offered with a claim of adherence to this guide will meet certain absolute purity and contaminant detectability requirements matched to the needs of current SFE or SFC techniques. The use of this guide allows different SFE or SFC CO2 product offerings to be compared on an equal purity basis.  
1.3 This guide considers contaminants to be those components that either cause detector signals that interfere with those of the target analytes or physically impede the SFE or SFC experiment.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are 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 responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

Status
Published
Publication Date
30-Nov-2019
ICS
71.100.20 - Gases for industrial application
Technical Committee
E13 - Molecular Spectroscopy and Separation Science
Drafting Committee
E13.19 - Separation Science
Current Stage
Ref Project

Relations

Refers
ASTM D4178-82(2017) - Standard Practice for Calibrating Moisture Analyzers
Effective Date
01-Oct-2017
Refers
ASTM E594-96(2019) - Standard Practice for Testing Flame Ionization Detectors Used in Gas or Supercritical Fluid Chromatography
Effective Date
01-Sep-2019
Refers
ASTM E260-96(2019) - Standard Practice for Packed Column Gas Chromatography
Effective Date
01-Sep-2019
Refers
ASTM E697-96(2019) - Standard Practice for Use of Electron-Capture Detectors in Gas Chromatography
Effective Date
01-Sep-2019
Refers
ASTM E1449-92(2019) - Standard Guide for Supercritical Fluid Chromatography Terms and Relationships
Effective Date
01-Dec-2019
Refers
ASTM D3686-20 - Standard Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activated Charcoal Tube Adsorption Method)
Effective Date
01-Mar-2020
Refers
ASTM D2504-88(2015) - Standard Test Method for Noncondensable Gases in C<inf>2</inf> and Lighter Hydrocarbon Products by Gas Chromatography
Effective Date
01-Jun-2015

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ASTM E1747-95(2019) - Standard Guide for Purity of Carbon Dioxide Used in Supercritical Fluid ApplicationsASTM E1747-95(2019) - Standard Guide for Purity of Carbon Dioxide Used in Supercritical Fluid Applications
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ASTM E1747-95(2019) - Standard Guide for Purity of Carbon Dioxide Used in Supercritical Fluid Applications
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This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1747 − 95 (Reapproved 2019)
Standard Guide for
Purity of Carbon Dioxide Used in Supercritical Fluid
1
Applications
This standard is issued under the fixed designation E1747; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Therapidcommercialdevelopmentofcarbondioxideforuseinsupercriticalfluidextraction(SFE)
and supercritical fluid chromatography (SFC) has hastened the need to establish common purity
standards to be specified by specialty gas suppliers. As a consequence of its isolation from
petrochemical side-streams or as a by-product of fermentation or ammonia synthesis, carbon dioxide
contains a wide range of impurities that can interfere with analytical quantification or instrument
operation.Thisguideisintendedtoserveasaguidetospecialtygassuppliersfortestingthesuitability
of carbon dioxide for use in SFC and SFE applications.
1. Scope responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
1.1 Thisguidedefinespuritystandardsforcarbondioxideto
mine the applicability of limitations prior to use.
ensure the suitability of liquefied carbon dioxide gas for use in
1.6 This international standard was developed in accor-
SFE and SFC applications (see Guide E1449 for definitions of
dance with internationally recognized principles on standard-
terms).This guide defines quantitation, labeling, and statistical
ization established in the Decision on Principles for the
standards for impurities in carbon dioxide that are necessary
Development of International Standards, Guides and Recom-
for successful SFE or SFC laboratory work, and it suggests
mendations issued by the World Trade Organization Technical
methods of analysis for quantifying these impurities.
Barriers to Trade (TBT) Committee.
1.2 Thisguideisprovidedforusebyspecialtygassuppliers
2. Referenced Documents
who manufacture carbon dioxide specifically for SFE or SFC
2
applications. SFE or SFC carbon dioxide (CO ) products
2
2.1 ASTM Standards:
offered with a claim of adherence to this guide will meet
D2504Test Method for Noncondensable Gases in C and
2
certain absolute purity and contaminant detectability require-
Lighter Hydrocarbon Products by Gas Chromatography
ments matched to the needs of current SFE or SFC techniques.
D2820Test Method for C Through C Hydrocarbons in the
3
TheuseofthisguideallowsdifferentSFEorSFCCO product
2
Atmosphere by Gas Chromatography (Withdrawn 1993)
offerings to be compared on an equal purity basis.
D3670Guide for Determination of Precision and Bias of
Methods of Committee D22
1.3 This guide considers contaminants to be those compo-
D3686Practice for Sampling Atmospheres to Collect Or-
nentsthateithercausedetectorsignalsthatinterferewiththose
ganic Compound Vapors (Activated Charcoal Tube Ad-
of the target analytes or physically impede the SFE or SFC
sorption Method)
experiment.
D3687Test Method for Analysis of Organic Compound
1.4 The values stated in SI units are to be regarded as
VaporsCollectedbytheActivatedCharcoalTubeAdsorp-
standard. No other units of measurement are included in this
tion Method
standard.
D4178Practice for Calibrating Moisture Analyzers
1.5 This standard does not purport to address all of the
D4532Test Method for Respirable Dust in Workplace At-
safety concerns, if any, associated with its use. It is the
mospheres Using Cyclone Samplers
1 2
This guide is under the jurisdiction of ASTM Committee E13 on Molecular For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Spectroscopy and Separation Science and is the direct responsibility of Subcom- contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
mittee E13.19 on Separation Science. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Dec. 1, 2019. Published December 2019. Originally the ASTM website.
3
approved in 1995. Last previous edition approved in 2011 as E1747–95(2011). The last approved version of this historical standard is referenced on
DOI: 10.1520/E1747-95R19. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1747 − 95 (2019)
E260Practice for Packed Column Gas Chromatography interferencesduringSFCapplications;thisislessofaproblem
E355PracticeforGasChromatographyTermsandRel
...

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SIGNIFICANCE AND USE
4.1 Mixed flowing gas (MFG) tests are used to simulate or amplify exposure to environmental conditions which electrical contacts or connectors can be expected to experience in various application environments (1, 2).4  
4.2 Test samples which have been exposed to MFG tests have ranged from bare metal surfaces, to electrical connectors, and to complete assemblies.  
4.3 The specific test conditions are usually chosen so as to simulate, in the test laboratory, the effects of certain representative field environments or environmental severity levels on standard metallic surfaces, such as copper and silver coupons or porous gold platings (1, 2).  
4.4 Because MFG tests are simulations, both the test conditions and the degradation reactions (chemical reaction rate, composition of reaction products, etc.) may not always resemble those found in the service environment of the product being tested in the MFG test. A guide to the selection of simulation conditions suitable for a variety of environments is found in Guide B845.  
4.5 The MFG exposures are generally used in conjunction with procedures which evaluate contact or connector electrical performance such as measurement of electrical contact resistance before and after MFG exposure.  
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1.1 This practice provides procedures for conducting environmental tests involving exposures to controlled quantities of corrosive gas mixtures.  
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Standard Test Method for Determination of Trace Gaseous Contaminants in Hydrogen Fuel by Fourier Transform Infrared (FTIR) Spectroscopy

SIGNIFICANCE AND USE
5.1 Fuel cell users have implicated trace impurities in feed gases as compromising the performance and lifespan of proton exchange membrane fuel cells (PEMFCs). PEMFCs may be damaged by the presence of some contaminants through poisoning of fuel cell electrode materials; therefore detection of these impurities at low concentrations is critical to fuel cell manufacturers and feed gas suppliers in order to support the facilities and infrastructure required for widespread applicability of fuel cells in transportation and energy production. With field-portable equipment, this test method can be used to quickly analyze hydrogen fuel for impurities at vehicle fueling stations or storage tanks used to supply stationary power plants. This test method can also be used by gas suppliers, customers, and regulatory agencies to certify hydrogen fuel quality.  
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SCOPE
1.1 This test method employs an FTIR gas analysis system for the determination of trace impurities in gaseous hydrogen fuels relative to the hydrogen fuel quality limits described in SAE TIR J2719 (April 2008) or in hydrogen fuel quality standards from other governing bodies. This FTIR method is used to quantify gas phase concentrations of multiple target contaminants in hydrogen fuel either directly at the fueling station or on an extracted sample that is sent to be analyzed elsewhere. Multiple contaminants can be measured simultaneously as long as they are in the gaseous phase and absorb in the infrared wavelength region. The detection limits as well as specific target contaminants for this standard were selected based upon those set forth in SAE TIR J2719.  
1.2 This test method allows the tester to determine which specific contaminants for hydrogen fuel impurities that are in the gaseous phase and are active infrared absorbers which meet or exceed the detection limits set by SAE TIR J2719 for their particular FTIR instrument. Specific target contaminants include, but are not limited to, ammonia, carbon monoxide, carbon dioxide, formaldehyde, formic acid, methane, ethane, ethylene, propane, and water. This test method may be extended to other impurities provided that they are in the gaseous phase or can be vaporized and are active infrared absorbers.  
1.3 This test method is intended for analysis of hydrogen fuels used for fuel cell feed gases or for internal combustion engine fuels. This method may also be extended to the analysis of high purity hydrogen gas used for other applications including industrial applications, provided that target impurities and required limits are also identified.  
1.4 This test method can be used to analyze hydrogen fuel sampled directly at the point-of-use from fueling station nozzles or other feed gas sources. The sampling apparatus includes a pressure regulator and metering valve to provide an appropriate gas stream for direct analysis by the FTIR spectrometer.  
1.5 This test method can also be used to analyze samples captured in storage vessels from point-of-use or other sources. Analysis of the stored samples can be performed either in a mobile laboratory near the sample source or in a standard analytical laboratory.  
1.6 A test plan should be prepared that includes (1) the specific impurity species to be measured, (2) the concentration limits for each impurity species, and (3) the determination of the minimum detectable concentration for each impurity species as measured on the apparatus before testing.  
1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.7.1 Exception—All values are based upon common terms used in the industry of those particular values and when not consistent with SI units, the appropriate...

  • Standard
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  • Standard
    13 pages
    English language
    sale 15% off