ASTM D5507-21a

Standard Test Method for Determination of Trace Organic Impurities in Monomer Grade Vinyl Chloride by Capillary Column/Multidimensional Gas Chromatography

SIGNIFICANCE AND USE
5.1 The multidimensional approach permits all of the trace impurities to be well separated from the main vinyl chloride peak, thereby improving quantitative accuracy over established packed column methods.  
5.2 The minimum detection limit (MDL) for all components of interest has been shown to be well below 500 ppb for this test method.
SCOPE
1.1 This is a general-purpose capillary-based test method for the determination of trace level impurities in high-purity vinyl chloride. This test method uses serially coupled capillary PLOT columns in conjunction with the multidimensional techniques of column switching and cryogenic trapping to permit the complete separation of the 11 key vinyl chloride impurities in a single 25-min run.  
Note 1: There is no known ISO equivalent to this standard.  
1.2 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 regulatory limitations prior to use. Specific hazards statements are given in Section 8.  
1.3 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-Apr-2021
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.70 - Analytical Methods

Relations

• Refers: ASTM D883-24 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2024
• Refers: ASTM D883-23 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2023
• Refers: ASTM E456-13a(2022)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2022
• Refers: ASTM F307-13(2020) - Standard Practice for Sampling Pressurized Gas for Gas Analysis
• Effective Date: 01-Apr-2020
• Refers: ASTM D883-20 - Standard Terminology Relating to Plastics
• Effective Date: 01-Jan-2020
• Refers: ASTM D883-19c - Standard Terminology Relating to Plastics
• Effective Date: 01-Aug-2019
• Refers: ASTM D883-19a - Standard Terminology Relating to Plastics
• Effective Date: 15-Apr-2019
• Refers: ASTM D883-19 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2019
• Refers: ASTM D883-18a - Standard Terminology Relating to Plastics
• Effective Date: 01-Dec-2018
• Refers: ASTM D883-18 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2018
• Refers: ASTM D1600-18 - Standard Terminology for Abbreviated Terms Relating to Plastics (Withdrawn 2024)
• Effective Date: 01-Jan-2018
• Refers: ASTM E456-13A(2017)e3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM E2935-17 - Standard Practice for Conducting Equivalence Testing in Laboratory Applications
• Effective Date: 01-Oct-2017
• Refers: ASTM E456-13A(2017)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM D883-17 - Standard Terminology Relating to Plastics
• Effective Date: 15-Aug-2017

Overview

ASTM D5507-21a is the standard test method developed by ASTM International for the determination of trace organic impurities in monomer grade vinyl chloride using capillary column and multidimensional gas chromatography. This method is specifically designed for analyzing high-purity vinyl chloride, enabling the detection and quantitation of low-level impurities that may impact product quality and regulatory compliance. The test leverages multidimensional capillary gas chromatography with advanced column-switching and cryogenic techniques to achieve excellent separation and measurement accuracy.

Key Topics

• Multidimensional Gas Chromatography: Utilizes serially coupled capillary PLOT columns with switching and trapping to separate trace impurities from the bulk vinyl chloride effectively.
• Precision and Sensitivity: Capable of detecting organic impurities at concentrations well below 500 ppb, markedly improving accuracy over traditional packed column methods.
• Relevant Impurities: Targets 11 key trace organic impurities potentially found in monomer grade vinyl chloride, integral to ensuring product purity.
• Calibration and Quality Assurance: Requires the use of primary and secondary certified reference standards to ensure method reliability and reproducibility.
• Safety Considerations: Highlights the need for appropriate safety, health, and environmental practices due to the hazardous nature of vinyl chloride.

Applications

ASTM D5507-21a serves a critical role in industries where the purity of vinyl chloride monomer is essential, such as:

• Polyvinyl Chloride (PVC) Production: Detecting and controlling trace organic impurities supports the consistent manufacturing of high-quality PVC resins and derivatives.
• Quality Control Laboratories: Used for routine quality assessment of vinyl chloride before polymerization, helping prevent downstream contamination or performance issues in finished plastic products.
• Regulatory Compliance: Supports compliance with local and international regulations regarding residual impurities in raw chemical feedstocks.
• Research and Method Validation: Provides a reliable analytical foundation for laboratories developing or validating new testing protocols for trace VOCs in bulk chemicals.

Related Standards

The following referenced ASTM standards offer complementary terminology, sampling, and procedural guidance relevant to the application of ASTM D5507-21a:

• ASTM D883 - Standard Terminology Relating to Plastics
• ASTM D1600 - Terminology for Abbreviated Terms Relating to Plastics
• ASTM E456 - Terminology Relating to Quality and Statistics
• ASTM E2935 - Practice for Conducting Equivalence Tests for Comparing Testing Processes
• ASTM F307 - Practice for Sampling Pressurized Gas for Gas Analysis

Note: There is currently no known ISO equivalent to ASTM D5507-21a.

Practical Value

Implementing ASTM D5507-21a ensures:

• Accurate impurity profiling in high-purity vinyl chloride to safeguard process reliability and end-product quality.
• Enhanced laboratory efficiency by enabling the separation and quantitation of multiple impurities in a single chromatographic run, typically lasting 25 minutes.
• Risk management by minimizing the chances of undetected contaminants entering the supply chain or final PVC products.
• Improved detection and quantitation limits, supporting industry efforts to meet increasingly stringent standards for raw material purity.

By adopting this standard, manufacturers, laboratories, and regulatory bodies gain a robust methodology for monitoring trace organic impurities in monomer grade vinyl chloride, supporting both product excellence and regulatory assurance.

Standards Content (Sample)

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: D5507 − 21a
Standard Test Method for
Determination of Trace Organic Impurities in Monomer
Grade Vinyl Chloride by Capillary Column/Multidimensional
Gas Chromatography
This standard is issued under the fixed designation D5507; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* 3. Terminology
1.1 This is a general-purpose capillary-based test method 3.1 Definitions—For definitions of terms in this test method
for the determination of trace level impurities in high-purity relating to plastics, refer to Terminology D883. For abbrevia-
vinyl chloride. This test method uses serially coupled capillary tions used in this test method, refer toTerminology D1600. For
PLOT columns in conjunction with the multidimensional definitions of terms that appear in this test method relating to
techniques of column switching and cryogenic trapping to quality and statistics, refer to Terminology E456.
permit the complete separation of the 11 key vinyl chloride
4. Summary of Test Method
impurities in a single 25-min run.
4.1 The liquid vinyl chloride sample or calibration standard
NOTE 1—There is no known ISO equivalent to this standard.
is injected either directly using a high-pressure liquid sampling
1.2 This standard does not purport to address all of the
valveoralternatelyasanexpandedgas.Anappropriatevolume
safety concerns, if any, associated with its use. It is the
of the liquid or gas sample is injected to enable the required
responsibility of the user of this standard to establish appro-
detection limits to be achieved.Apreliminary GC separation is
priate safety, health, and environmental practices and deter-
achieved on a 6-m pre-column, the purpose of which is to
mine the applicability of regulatory limitations prior to use.
removethebulkofthevinylchloridepeakfromthetracepeaks
Specific hazards statements are given in Section 8.
of interest. Two heart-cut transfers are made from this pre-
1.3 This international standard was developed in accor-
column separation, which sends selected portions to a second
dance with internationally recognized principles on standard-
column for additional separation. These two cuts incorporate
ization established in the Decision on Principles for the
10 of the 11 trace impurities of interest, but they exclude 1,2
Development of International Standards, Guides and Recom-
ethylenedichlorideandthebulkofthevinylchloridepeak.The
mendations issued by the World Trade Organization Technical
1,2 EDC peak is eluted from the 6-m pre-column and detected
Barriers to Trade (TBT) Committee.
at the first FID after the two cuts are made.
2. Referenced Documents
4.2 The components eluting to the two FID detectors are
identified and quantitated by comparing their retention times
2.1 ASTM Standards:
and area counts to those obtained previously from a calibration
D883 Terminology Relating to Plastics
standard run under identical conditions.
D1600 Terminology forAbbreviatedTerms Relating to Plas-
tics
5. Significance and Use
E456 Terminology Relating to Quality and Statistics
E2935 Practice for Conducting Equivalence Tests for Com- 5.1 The multidimensional approach permits all of the trace
paring Testing Processes
impurities to be well separated from the main vinyl chloride
F307 Practice for Sampling Pressurized Gas for Gas Analy-
peak,therebyimprovingquantitativeaccuracyoverestablished
sis packed column methods.
5.2 Theminimumdetectionlimit(MDL)forallcomponents
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
of interest has been shown to be well below 500 ppb for this
and is the direct responsibility of Subcommittee D20.70 on Analytical Methods.
test method.
Current edition approved May 1, 2021. Published May 2021. Originally
approved in 1994. Last previous edition approved in 2021 as D5507 – 21. DOI:
6. Apparatus
10.1520/D5507-21A.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.1 Instrumentation:
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.1.1 Capillary Column/Multidirectional Gas
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Chromatograph, equipped as follows:
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5507 − 21a
7.4 Liquid CO —Coolant, bone-dry grade, liquid-delivery,
1200-psi helium pad recommended.
7.5 Standards:
7.5.1 Primary Standard—Theprimarystandardisacertified
reference standard, which is blended into a stable nitrogen or
helium matrix. The component concentrations should be pre-
pared and reported on an as-in-vinyl chloride basis. The
concentrations of the various components in this standard
should also represent typical values expected for the particular
process or sample. The following is a typical calibration
standard composition:
Component Mole, ppm Weight, ppm
Ethylene 29.4 13.2
Propylene 20.0 13.5
Acetylene 6.8 2.8
Butane-1 6.8 6.1
Trans-butene-2 7.1 6.4
Cis-butene-2 7.5 6.7
1,3 butadiene 6.5 5.6
Methyl chloride 36.8 29.7
Vinyl acetylene 12.2 10.2
FIG. 1 Procedure B: On-Line Vaporization Using the LPG Vapor-
Ethyl chloride 15.9 16.4
izing Injector
1,2 ethylene dichloride 11.8 18.7
Nitrogen balance
7.5.2 Secondary Standard—The secondary standard is a
6.1.1.1 Split/Splitless Injector System—Must be demon-
vinylchloride-basedblend,whichisusedformethodsetupand
strated to be free of discrimination effects induced by vapor
day-to-day method calibration. This standard is prepared from
viscosity differences if helium- or nitrogen-based gas standards
actual vinyl chloride product, which is spiked where appropri-
are to be used for instrument calibration.
ate to yield the approximate levels represented in the nitrogen-
6.1.1.2 Dual Flame-Ionization Detectors.
based primary standard. The final concentrations should be
6.1.1.3 Column Switching Device A pneumatics control
determined by averaging the results from multiple runs, which
system.
are referenced to the primary standard. This calibration/
6.1.1.4 Sub-Ambient Oven Temperature Control (optional).
recalibration process may be conducted using an alternate GC
6.1.1.5 LPG Vaporizing Injector, (Fig. 1).
procedure.
6.2 Data System, permits the acquisition, storage, and re-
8. Hazards
duction of the output signals from the two FIDs simultane-
ously. After the initial method development, however, it is
8.1 Appropriate caution must be exercised in handling the
possible to consolidate the output to a single integrator using
sample due to the suspected carcinogenicity of vinyl chloride.
the instruments signal switching capability.
Any excess of sample beyond that actually injected into the
column should be routed to a purge waste line to be passed to
6.3 Columns:
a vent hood or other suitable disposal location. This excess
6.3.1 Pre-Column—100 cm of 0.20-mm inside diameter
sample includes the inlet splitter vent flow and the sample-loop
fused silica fixed restrictor coupled to the front ofa6mby
purge flow in the case in which a gas-valve injection is being
0.53-mm inside diameter non-polar PLOT.
made.
6.3.2 Analytical Column—9 m by 0.53-mm inside diameter
non-polar PLOT plus 25 m by 0.53 mm inside diameter polar
9. Sampling
PLOT.
9.1 This section is to be followed for all samples, including
6.4 Syringes—A range of high-quality gas-tight syringes
unknown samples and the synthetic standards.
representing volumes from 0.5 to 25 mL should be available.
These syringes should be equipped with PTFE-tipped plunger
9.2 Samples should be supplied to the laboratory in high-
seals and on and off syringe valves to prevent the loss of gas
pressure sample cylinders, obtained using the procedure de-
sample.
scribed in Practice F307 or similar standards.
9.3 Place the cylinder in a horizontal position in a safe place
7. Reagents and Materials
such as a hood. Check to see that the container is at least
7.1 Helium—Carrier gas, zero grade, high quality. Traps
one-half full by opening the valve slightly. The container is at
should be placed in the supply lines leading to the gas
least one-half full if liquid is emitted (a white cloud of vapors).
chromatograph. These traps should reduce oxygen, moisture,
Donotanalyzeanysamplesoruseanysyntheticstandardifthe
and hydrocarbons to the lowest possible levels.
liquid in the container is below this amount.
7.2 Hydrogen—Flame gas, high-purity (hydrocarbon free).
9.4 Placethecylinderinaverticalpositionandrepressureto
7.3 Air—Flame gas, high-purity (hydrocarbon free). 1.208 MPa (175 psig) with the chromatographic carrier or
D5507 − 21a
FIG. 3 By-Pass Operation
lines up to the sample cylinder. Close the valve to the vacuum
source and allow the sample loop to fill with sample up to
atmospheric pressure. Repeat the evacuation and filling of the
FIG. 2 Procedure A: Off-Line Vaporization
sample loop with vaporized sample. Turn the valve so that the
vaporized sample is displaced with carrier gas into the chro-
equivalent inert gas through the valve at the top of the cylinder,
matograph.
ensuring that no air enters during the operation.
9.5.2.2 Procedure B—On-line vaporization using the LPG
Vaporizing Injector (or equivalent).An alternate approach that
9.5 Use either of the following two procedures for obtaining
has been used successfully for the automated on-line LPG to
a sample from the container:
vapor conversion and sample introduction is shown in Fig. 1.
9.5.1 Liquid Sample—Connect the cylinder to the liquid
The vapor injection occurs in the upper half of this assembly
valve on the chromatograph using a minimum length of
labeled “hot zone.” The automated injection process proceeds
connecting tubing, so that sample is withdrawn from the
as follows:
bottom of the cylinder and a liquid sample is obtained. The
(1) The lower valve of the sample cylinder is opened to
liquid valve on the chromatograph must be designed in such a
permit the flow of liquid to the fixed restricter (35 to 45-µm
mannerthatfullsamplepressurecanbemaintainedthroughthe
pinpoint restriction or equivalent).
valve without leaking and that means are provided for trapping
(2) The constant-pressure force above the liquid drives
a liquid sample in the chromatograph valve under static flow
liquid across the fixed restrictor at a constant rate.
conditions. With the exit of the chromatograph valve closed,
(3) The vapor formed in the heated vaporizer tube is mixed
open the valve on the cylinder. Open the exit from the
prior to passing through the block out valve and on through the
chromatograph valve slowly so that liquid flows through the
sample loop to vent.
connecting line and valve. Close the exits so that the liquid
(4) The sample loop purge is permitted to proceed for a
sample is trapped in the valve. Perform the necessary opera-
fixedperiodoftimethatissufficienttoensureacompletepurge
tions to introduce the liquid sample into the chromatograph
of the loop volume.
column.
(5) The block out valve automatically shuts off the flow of
9.5.2 Vaporized Sample:
vapor to the sample loop after the sample-loop purge period.
9.5.2.1 Procedure A—Off-Line Vaporization:
(6) Ashort delay period is permitted after sample block out
(1) Assemble the apparatus in a manner similar to that
and before sample injection.This delay ensures that the sample
illustrated in Fig. 2. Disconnect the 1700-cm cylinder at E and
loop is permitted to decay back to atmospheric pressure.
evacuate. Close Valve B and open Valves C and D, allowing
(7) The gas sampling valve is then actuated to inject the
the liquid sample to flow
...

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. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5507 − 21 D5507 − 21a
Standard Test Method for
Determination of Trace Organic Impurities in Monomer
Grade Vinyl Chloride by Capillary Column/Multidimensional
Gas Chromatography
This standard is issued under the fixed designation D5507; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This is a general-purpose capillary-based test method for the determination of trace level impurities in high-purity vinyl
chloride. This test method uses serially coupled capillary PLOT columns in conjunction with the multidimensional techniques of
column switching and cryogenic trapping to permit the complete separation of the 11 key vinyl chloride impurities in a single
25-min run.
NOTE 1—There is no known ISO equivalent to this standard.
1.2 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
regulatory limitations prior to use. Specific hazards statements are given in Section 8.
1.3 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.
2. Referenced Documents
2.1 ASTM Standards:
D883 Terminology Relating to Plastics
D1600 Terminology for Abbreviated Terms Relating to Plastics
E456 Terminology Relating to Quality and Statistics
E2935 Practice for Conducting Equivalence Tests for Comparing Testing Processes
F307 Practice for Sampling Pressurized Gas for Gas Analysis
3. Terminology
3.1 Definitions—Terminology is in accordance with Terminologies For definitions of terms in this test method relating to plastics,
refer to Terminology D883 and . For abbreviations used in this test method, refer to Terminology D1600 unless otherwise
indicated. For definitions of terms that appear in this test method relating to quality and statistics, refer to Terminology E456.
This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.70 on Analytical Methods.
Current edition approved Jan. 15, 2021May 1, 2021. Published January 2021May 2021. Originally approved in 1994. Last previous edition approved in 20122021 as
D5507 – 99D5507 – 21.(2012). DOI: 10.1520/D5507-21.10.1520/D5507-21A.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5507 − 21a
4. Summary of Test Method
4.1 The liquid vinyl chloride sample or calibration standard is injected either directly using a high-pressure liquid sampling valve
or alternately as an expanded gas. An appropriate volume of the liquid or gas sample is injected to enable the required detection
limits to be achieved. A preliminary GC separation is achieved on a 6-m pre-column, the purpose of which is to remove the bulk
of the vinyl chloride peak from the trace peaks of interest. Two heart-cut transfers are made from this pre-column separation, which
sends selected portions to a second column for additional separation. These two cuts incorporate 10 of the 11 trace impurities of
interest, but they exclude 1,2 ethylene dichloride and the bulk of the vinyl chloride peak. The 1,2 EDC peak is eluted from the
6-m pre-column and detected at the first FID after the two cuts are made.
4.2 The components eluting to the two FID detectors are identified and quantitated by comparing their retention times and area
counts to those obtained previously from a calibration standard run under identical conditions.
5. Significance and Use
5.1 The multidimensional approach permits all of the trace impurities to be well separated from the main vinyl chloride peak,
thereby improving quantitative accuracy over established packed column methods.
5.2 The minimum detection limit (MDL) for all components of interest has been shown to be well below 500 ppb for this test
method.
6. Apparatus
6.1 Instrumentation:
6.1.1 Capillary Column/Multidirectional Gas Chromatograph, equipped as follows:
6.1.1.1 Split/Splitless Injector System—Must be demonstrated to be free of discrimination effects induced by vapor viscosity
differences if helium- or nitrogen-based gas standards are to be used for instrument calibration.
6.1.1.2 Dual Flame-Ionization Detectors.
6.1.1.3 Column Switching Device A pneumatics control system.
6.1.1.4 Sub-Ambient Oven Temperature Control (optional).
6.1.1.5 LPG Vaporizing Injector, (Fig. 1).
6.2 Data System, permits the acquisition, storage, and reduction of the output signals from the two FIDs simultaneously. After the
initial method development, however, it is possible to consolidate the output to a single integrator using the instruments signal
switching capability.
6.3 Columns:
6.3.1 Pre-Column—100 cm of 0.20-mm inside diameter fused silica fixed restrictor coupled to the front of a 6 m by 0.53-mm
inside diameter.diameter non-polar PLOT.
6.3.2 Analytical Column—9 m by 0.53-mm inside diameter non-polar PLOT plus 25 m by 0.53 mm inside diameter.diameter polar
PLOT.
6.4 Syringes—A range of high-quality gas-tight syringes representing volumes from 0.5 to 25 mL should be available. These
syringes should be equipped with PTFE-tipped plunger seals and on and off syringe valves to prevent the loss of gas sample.
7. Reagents and Materials
7.1 Helium—Carrier gas, zero grade, high quality. Traps should be placed in the supply lines leading to the gas chromatograph.
These traps should reduce oxygen, moisture, and hydrocarbons to the lowest possible levels.
D5507 − 21a
FIG. 1 Procedure B: On-Line Vaporization Using the LPG Vaporizing Injector
7.2 Hydrogen—Flame gas, high-purity (hydrocarbon free).
7.3 Air—Flame gas, high-purity (hydrocarbon free).
7.4 Liquid CO —Coolant, bone-dry grade, liquid-delivery, 1200-psi helium pad recommended.
7.5 Standards:
7.5.1 Primary Standard—The primary standard is a certified reference standard, which is blended into a stable nitrogen or helium
matrix. The component concentrations should be prepared and reported on an as-in-vinyl chloride basis. The concentrations of the
various components in this standard should also represent typical values expected for the particular process or sample. The
following is a typical calibration standard composition:
Component Mole, ppm Weight, ppm
Ethylene 29.4 13.2
Propylene 20.0 13.5
Acetylene 6.8 2.8
Butane-1 6.8 6.1
Trans-butene-2 7.1 6.4
Cis-butene-2 7.5 6.7
1,3 butadiene 6.5 5.6
Methyl chloride 36.8 29.7
Vinyl acetylene 12.2 10.2
Ethyl chloride 15.9 16.4
1,2 ethylene dichloride 11.8 18.7
Nitrogen balance
7.5.2 Secondary Standard—The secondary standard is a vinyl chloride-based blend, which is used for method setup and
day-to-day method calibration. This standard is prepared from actual vinyl chloride product, which is spiked where appropriate to
yield the approximate levels represented in the nitrogen-based primary standard. The final concentrations should be determined by
averaging the results from multiple runs, which are referenced to the primary standard. This calibration/recalibration process may
be conducted using an alternate GC procedure.
8. Hazards
8.1 Appropriate caution must be exercised in handling the sample due to the suspected carcinogenicity of vinyl chloride. Any
D5507 − 21a
FIG. 2 Procedure A: Off-Line Vaporization
excess of sample beyond that actually injected into the column should be routed to a purge waste line to be passed to a vent hood
or other suitable disposal location. This excess sample includes the inlet splitter vent flow and the sample-loop purge flow in the
case in which a gas-valve injection is being made.
9. Sampling
9.1 This section is to be followed for all samples, including unknown samples and the synthetic standards.
9.2 Samples should be supplied to the laboratory in high-pressure sample cylinders, obtained using the procedure described in
Practice F307 or similar standards.
9.3 Place the cylinder in a horizontal position in a safe place such as a hood. Check to see that the container is at least one-half
full by opening the valve slightly. The container is at least one-half full if liquid is emitted (a white cloud of vapors). Do not analyze
any samples or use any synthetic standard if the liquid in the container is below this amount.
9.4 Place the cylinder in a vertical position and repressure to 1.208 MPa (175 psig) with the chromatographic carrier or equivalent
inert gas through the valve at the top of the cylinder, ensuring that no air enters during the operation.
9.5 Use either of the following two procedures for obtaining a sample from the container:
9.5.1 Liquid Sample—Connect the cylinder to the liquid valve on the chromatograph using a minimum length of connecting
tubing, so that sample is withdrawn from the bottom of the cylinder and a liquid sample is obtained. The liquid valve on the
chromatograph must be designed in such a manner that full sample pressure can be maintained through the valve without leaking
and that means are provided for trapping a liquid sample in the chromatograph valve under static flow conditions. With the exit
of the chromatograph valve closed, open the valve on the cylinder. Open the exit from the chromatograph valve slowly so that
liquid flows through the connecting line and valve. Close the exits so that the liquid sample is trapped in the valve. Perform the
necessary operations to introduce the liquid sample into the chromatograph column.
9.5.2 Vaporized Sample:
9.5.2.1 Procedure A—Off-Line Vaporization:
(1) Assemble the apparatus in a manner similar to that illustrated in Fig. 2. Disconnect the 1700-cm cylinder at E and evacuate.
Close Valve B and open Valves C and D, allowing the liquid sample to flow into the small cylinder. Open Valve B slowly and allow
the sample to flow through until a steady slow stream of liquid emerges from B. Close Valves B, C, and D in that order, trapping
a portion of the liquid sample in the pipe cylinder. Attach the evacuated cylinder (1700-cm volume) at E. Open Valve A and then
Valve B. The liquid will expand, filling the larger cylinder. Close Valve A and disconnect at E.
D5507 − 21a
FIG. 3 By-Pass Operation
NOTE 2—To prevent possible rupture of the liquid-filled pipe cylinder, the sample cylinder and its contents should be at room temperature prior to
sampling, and the liquid should be allowed to remain in the pipe cylinder for only a minimum of time.
(2) Connect the cylinder containing the vaporized sample to the chromatograph gas valve. Evacuate the sample loop and the
lines up to the sample cylinder. Close the valve to the vacuum source and allow the sample loop to fill with sample up to
atmospheric pressure. Repeat the evacuation and filling of the sample loop with vaporized sample. Turn the valve so that the
vaporized sample is displaced with carrier gas into the chromatograph.
9.5.2.2 Procedure B—On-line vaporization using the LPG Vaporizing Injector (or equivalent). An alternate approach that has been
used successfully for the automated on-line LPG to vapor conversion and sample introduction is shown in Fig. 1. The vapor
injection occurs in the upper half of this assembly labeled “hot zone.” The automated injection process proceeds as follows:
(1) The lower valve of the sample cylinder is opened to permit the flow of liquid to the fixed restricter (35 to 45-μm pinpoint
restriction or equivalent).
(2) The constant-pressure force above the liquid drives liquid across the fixed restrictor at a
...